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Pioneer Series Trust X

Filed: 4 Jun 21, 1:42pm
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-21108

Pioneer Series Trust X
(Exact name of registrant as specified in charter)

60 State Street, Boston, MA 02109
(Address of principal executive offices) (ZIP code)

Terrence J. Cullen, Amundi Asset Management, Inc.,
60 State Street, Boston, MA 02109
(Name and address of agent for service)


Registrant’s telephone number, including area code:  (617) 742-7825
Date of fiscal year end:  March 31, 2021

Date of reporting period: April 1, 2020 through March 31, 2021

Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1).  The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609.  The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. ss. 3507.


Pioneer Multi-Asset
Ultrashort Income Fund
Annual Report | March 31, 2021
A: MAFRX C: MCFRX C2: MAUCX K: MAUKX Y: MYFRX 
 
Paper copies of the Fund’s shareholder reports are no longer sent by mail, unless you specifically request paper copies of the reports from the Fund or from your financial intermediary, such as a broker-dealer, bank or insurance company. Instead, the reports are available on the Fund’s website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.
You may elect to receive all future reports in paper free of charge. If you invest directly with the Fund, you can inform the Fund that you wish to continue receiving paper copies of your shareholder reports by calling 1-800-225-6292.
If you invest through a financial intermediary, you can contact your financial intermediary to request that you continue to receive paper copies of your shareholder reports. Your election to receive reports in paper will apply to all funds held in your account if you invest through your financial intermediary or all funds held within the Pioneer Fund complex if you invest directly.





 

visit us: www.amundi.com/us


 

  
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Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 1

President’s Letter


Dear Shareholders,
The first few months of 2021 have brought some better news on the COVID-19 global pandemic front, as the deployment of the first approved COVID-19 vaccines is well underway, with expectations for widespread vaccine distribution by the middle of the year. In general, COVID-19 cases and related hospitalizations have been on the decline in the US, despite a few problematic “hot spots” in some states, and that has had a positive effect on overall market sentiment.
While there may finally be a light visible at the end of the pandemic tunnel, the long-term impact on the global economy from COVID-19, while currently unknown, is likely to be considerable. It is clear that several industries have already felt greater effects than others, and the markets, which do not thrive on uncertainty, have been volatile. With that said, in the first few months of 2021, equity markets and other so-called “riskier” assets, such as high-yield bonds, have outperformed investments regarded as less risky, such as government debt. In addition, we’ve witnessed the long-awaited rebound in the performance of cyclical stocks, or stocks of companies with greater exposure to the ebbs and flows of the economic cycle, as investors have appeared to embrace the potential for a more widespread reopening of the economy in the coming months. Additional fiscal stimulus from the US government in recent months has also helped provide some market momentum.
However, despite the dramatic market rebound since its March 2020 low point, volatility has remained elevated, with momentum rising and falling on seemingly every bit of positive or negative news about the virus. In addition, the recent US Presidential and Congressional elections have resulted in a power shift in Washington, DC, and that most likely portends some changes in fiscal policy above and beyond just additional pandemic-related stimulus. That, too, could lead to increased market volatility as investors analyze the various tax and spending plans, and wait to see what proposed policy alterations actually become law.
With the advent of COVID-19 in early 2020, we implemented our business continuity plan according to the new COVID-19 guidelines, and most of our employees have been working remotely since March 2020. To date, our operating environment has faced no interruption. I am proud of the careful planning that has taken place and confident we can maintain this environment for as long as is prudent. History in the making for a company that first opened its doors way back in 1928.
2 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Since 1928, Amundi US’s investment process has been built on a foundation of fundamental research and active management, principles which have guided our investment decisions for more than 90 years. We believe active management – that is, making active investment decisions – can help mitigate the risks during periods of market volatility. As 2020 has reminded us, investment risk can arise from a number of factors in today’s global economy, including slower or stagnating growth, changing U.S. Federal Reserve policy, oil price shocks, political and geopolitical factors and, unfortunately, major public health concerns such as a viral pandemic.
At Amundi US, active management begins with our own fundamental, bottom-up research process. Our team of dedicated research analysts and portfolio managers analyzes each security under consideration, communicating directly with the management teams of the companies issuing the securities and working together to identify those securities that best meet our investment criteria for our family of funds. Our risk management approach begins with each and every security, as we strive to carefully understand the potential opportunity, while considering any and all risk factors.
Today, as investors, we have many options. It is our view that active management can serve shareholders well, not only when markets are thriving, but also during periods of market stress.
As you consider your long-term investment goals, we encourage you to work with your financial professional to develop an investment plan that paves the way for you to pursue both your short-term and long-term goals.
We remain confident that the current crisis, like others in human history, will pass, and we greatly appreciate the trust you have placed in us and look forward to continuing to serve you in the future.
Sincerely,
Lisa M. Jones
Head of the Americas, President and CEO of US
Amundi Asset Management US, Inc.
May 2021
Any information in this shareowner report regarding market or economic trends or the factors influencing the Fund’s historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 3

 
Portfolio Management Discussion | 3/31/21
In the following interview, portfolio managers Seth Roman, Jonathan Sharkey, Noah Funderburk, and Nicolas Pauwels discuss the factors that influenced the performance of Pioneer Multi-Asset Ultrashort Income Fund during the 12-month period ended March 31, 2021. Mr. Roman, a vice president and a portfolio manager at Amundi Asset Management US, Inc. (Amundi US); Mr. Sharkey, a senior vice president and a portfolio manager at Amundi US; Mr. Funderburk, a vice president and a portfolio manager at Amundi US; and Mr. Pauwels, a vice president and a portfolio manager at Amundi US, are responsible for the day-to-day management of the Fund.
Q   How did the Fund perform during the 12-month period ended March 31, 2021?
A    Pioneer Multi-Asset Ultrashort Income Fund’s Class A shares returned 6.42% at net asset value (NAV) during the 12-month period ended March 31, 2021, while the Fund’s benchmark, the ICE Bank of America 3-Month US Dollar LIBOR Index (the ICE BofA Index), returned 0.64%. During the same period, the average return of the 231 mutual funds in Morningstar’s Ultrashort Bond category was 3.38%.
Q   How would you describe the market environment for fixed-income investors over the 12-month period ended March 31, 2021?
A    Entering the period, social-distancing and shelter-in-place measures enacted to help curb the spread of COVID-19 had profound economic effects and resulted in significant reductions in services consumption, manufacturing activity, construction, and labor demand.
The unprecedented decision to shut down much of the US economy in the spring of 2020 necessitated unprecedented monetary and fiscal policy responses. March 2020 saw the US Federal Reserve (Fed) jump into action by dusting off its 2008/2009 policy “playbook” and rapidly rolling out a raft of programs aimed at restoring market liquidity, facilitating credit availability, and boosting investors’ confidence. The measures included: reducing the benchmark federal funds rate target range to zero; a commitment to making unlimited purchases of US Treasuries and agency mortgage-backed securities (MBS); and providing support for commercial-paper issuance, mutual fund liquidity needs, and the issuance of asset-backed securities (ABS). On March 23, 2020, the Fed then opened an entirely new playbook with the announcement of purchasing programs in support of both the new-issue and secondary corporate bond markets. The end of March 2020 also saw US lawmakers approve a $2.2 trillion fiscal stimulus package for both individuals and businesses.
4 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 
The extraordinary support from policy makers in the wake of the pandemic was met with enthusiasm by the markets as the second quarter of 2020 got underway. Investors sought to put money to work at the now much-wider credit spreads, estimating that they would receive fair compensation (via higher yields) for taking on the increased default risk. (Credit spreads are commonly defined as the differences in yield between Treasuries and other types of fixed-income securities with similar maturities).
As the second quarter of 2020 progressed, investors became increasingly optimistic that steps toward reopening the economy would support something resembling a “V-shaped” recovery (a sudden, sharp rise). The result was a resurgence in positive sentiment towards riskier assets that allowed credit-sensitive areas of the bond market to recover much of their earlier losses, even as rising numbers of COVID-19 cases in a number of states raised concerns during the summer months.
The markets experienced some volatility over the next few months, but still continued to produce generally solid performance. Then, the emergency-use approval of the first COVID-19 vaccines, and the removal of political uncertainty with the finalization of the November US election results, led to an increase in investors’ confidence heading into 2021. In January, the outlook received a further boost when the Democrats won two runoff elections to gain control of the US Senate (in addition to the White House and the House of Representatives), thus increasing the odds of more fiscal stimulus from the US government. A $1.9 trillion stimulus package soon followed, with proposals for infrastructure and additional stimulus spending also in the offing.
Meanwhile, the successful rollouts of the COVID-19 vaccines in the US as the winter months progressed, combined with a general decline in COVID-19 cases and the ongoing reopening of the economies in certain US states, were other factors contributing to improved investor sentiment. Along with strong global manufacturing reports, those developments fueled increasing US Treasury yields and led to heightened inflation expectations as well as higher commodity prices. Late in the period, the markets received more good news as the Fed indicated that it would remain very “dovish” in its posture on monetary policy. Fed Chairman Jerome Powell reinforced the central bank’s intent to remain “on the sidelines” with regard to interest-rate hikes until at least 2023, based on the view that near-term increases in inflation above the Fed’s typical 2% target would be transitory, and not structural. To that point, the mid-March 2021 Federal Open Market Committee (FOMC) meeting gave Fed members an opportunity to reinforce their commitment to the new “flexible average inflation target” policy framework.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 5
 
Q   Can you review your principal investment strategies during the 12-month period ended March 31, 2021, and how the strategies affected the Fund’s benchmark-relative performance?
A   Positive contributions to the Fund’s benchmark-relative performance during the 12-month period were led by investments in securitized assets, with allocations to residential mortgage-backed securities (RMBS), commercial MBS (CMBS), and asset-backed securities (ABS) providing the largest benefits. The Fund has remained overweight to securitized assets versus its peers.
RMBS have benefited from a strong housing market and a continued decline in the number of mortgages in forbearance. The Standard & Poor’s CoreLogic Case-Schiller US National Home Price Index has shown an 11.2% year-over-year improvement in housing prices, the best performance since 2014. Forbearance rates have continued to decline, with the latest Fannie Mae/Freddie Mac data showing forbearance at 2.5%. With regard to the housing market, existing home sales have surprised to the upside of late. Within RMBS, the Fund held approximately 10% of its net assets (as of period-end) in credit-risk-transfer (CRT) issues, which transfer some of the risk of non-payment on residential mortgages from government-sponsored entities to the private sector. The positive housing news has supported investor sentiment for CRT issues and, in our view, CRTs have continued to offer compelling value, given low defaults and declining forbearance rates as well as extended forbearance periods.
The Fund’s CMBS exposures also contributed positively to benchmark-relative performance. The portfolio’s lodging single-asset/single-borrower spreads have benefited from recovering hotel revenues, in particular within the economy, limited service, and drive-to-destination hotel segments. Those hotel subsectors have recovered much of their COVID-19-driven revenue declines. We believe recoveries in fly-to-destination hotel and business-travel hotel revenues could follow suit, but at a slower pace. The CMBS and ABS hotel/vacation real estate markets have shown continued strength, with increased merger-and-acquisition activity. Some new leading indicators in hotel data have also been encouraging. Extended-stay hotels appear to have weathered the COVID-19 crisis well, while most others, such as limited-service hotels, saw significant declines, but have been recovering of late. The recovery trend has been more prominent in popular vacation destinations, such as Florida, and in US states that have reopened more broadly. Current expectations are that urban hotels, which typically have relied on business travel and conventions, could continue to see depressed revenues for the near future. Prices on bonds backed by hotels have rebounded substantially from the depths of one year ago, while
6 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21


bonds backed by other property types, such as multi-family, logistics, and offices, have mostly rebounded up to, or at least close to their pre-pandemic levels.
ABS exposures were another positive contributor to the Fund’s relative results for the 12-month period, as stronger-than-expected retail sales and the wider reopening of the economy have aided the performance of consumer-related sectors. Some non-traditional or “off-the-run” ABS sectors and the non-AAA-rated part of the capital structure within traditional ABS sectors have provided attractive investment opportunities, in our opinion, as the market’s rotation into securities that may potentially generate incremental yield has continued unabated. The US consumer has remained strong, with a 40-year high savings rate of 13.7% according to recent data, and income levels (even without fiscal stimulus) that have exceeded pre-pandemic levels. In addition, banks have continued to release loss reserves due to better-than-expected loss experience on their credit card and auto loan exposures. Meanwhile, used car prices have reached record highs, rising by 3.8% in February 2021 alone, for a 17.9% year-over-year gain. That was the fastest year-over-year gain since 2009, when the government’s “cash for clunkers” program created a supply/demand imbalance in the used car market. We have not been concerned with the credit quality of auto-related ABS, but these figures, in our view, represent another data point suggesting both pent-up demand and surplus consumer savings.
Other sector allocations that had positive effects on the Fund’s benchmark-relative performance during the 12-month period included exposure to financials and industrials issues within corporate credit, which fared well overall, despite short-term spread widening and volatility in the financials sector toward the end of the period.
Additional contributions to the Fund’s positive benchmark-relative returns came from allocations to bank loans and collateralized loan obligations (CLOs). Bank loans have been experiencing their highest new-issue market since 2014, and the loan market has seen lower demand for paper trading above par (face) value that could be at risk of refinancing, thus illustrating investors’ preference for new loan issues. Issues trading above par value have fallen in number from over 50% to 20% of the market, and so we believe both market and return prospects for bank loans have improved going forward. We believe bank loans have remained strong in general, although we have not been witnessing the torrid spread-compression we saw earlier in the 12-month period. Meanwhile, CLO demand has remained robust.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 7
 

Finally, an allocation to insurance-linked securities (ILS) aided the Fund’s benchmark-relative performance over the past 12 months. We believe ILS exposures could add value to the Fund, given that performance of ILS has typically been uncorrelated to the performance of other financial assets.
During a 12-month period that saw the Fund outperform the ICE BofA Index by a fairly wide margin, there were no notable detractors from benchmark-relative returns.
Q   Can you discuss the factors that affected the Fund’s income-generation, or distributions* to shareholders, either positively or negatively, during the 12-month period ended March 31, 2021?
A   Credit spreads narrowed over the 12-month period, which led to a reduction in the Fund’s income-generation. However, we believe the levels of income generated by the Fund have remained attractive, given the continued low-interest-rate environment.
Q   Did the Fund have any exposure to derivatives during the 12-month period ended March 31, 2021?
A   The Fund had light exposure to some index futures contracts during the 12-month period, which had a negligible effect on performance.
Q   What is your assessment of the current investment environment in the fixed-income markets?
A   The Fed has continued to message that it is willing to keep monetary policy accommodative for an extended period of time. While “an extended period of time” seems to be a purposefully vague duration, public comments from members of the FOMC have suggested that they could be thinking the “extended period” equals at least one year. Since the Fed has indicated that it will ignore this year’s expected rise in inflation and view it as transitory, the attention of both investors and policy makers could turn to 2022 inflation measures. If the FOMC, as suggested, waits for a full year with Core PCE (personal consumption) inflation at more than 2% before tightening monetary policy, rate hikes could be off the table until 2023, in our opinion. That would be consistent with the Fed’s own “dot plot” chart projections. (The Fed’s “dot” plot/projection is a quarterly chart summarizing the outlook for the federal funds rate for each of the FOMC’s members.)
* Distributions are not guaranteed.
8 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Market pricing, however, has reflected a somewhat faster pace for rate hikes, due in part to the possibility that the markets may not “buy” the Fed’s new operating framework. However, we feel it is important to understand that actual market pricing has reflected a combination of possible outcomes rather than single-point forecasts.
While we believe inflation is likely to be lower in 2022 than in 2021, the balance of inflation risks has been skewed to the upside, given massive debt-financed US fiscal stimulus and the prospect of government policies –such as a minimum wage hike, easier unionization, and generous unemployment benefits – that could potentially boost wage growth.
Given the likelihood of additional fiscal stimulus and a more-rapid US economic reopening, we have revised up our base-case 2021 US gross domestic product (GDP) growth forecast. The demand-driven growth dynamic could be positive for corporate fundamentals and consumer balance sheets. In turn, solid issuer fundamentals and still-elevated investor cash balances (earning close to 0% yield) may support further spread-asset performance.
We believe higher US Treasury yields present a risk to broad-market performance, to the extent that tighter financial conditions could start to weigh on economic activity. By our estimates, a 10-year US Treasury yield in the 2.50% to 3.00% area may likely become problematic for certain market segments and for economic growth. We currently regard the risk of such a move as minor; however, we have been monitoring conditions closely, as strong monthly economic data reports could push yields marginally higher in the coming months.
We continue to believe that the Fund offers a compelling option for investors seeking a strategic short-term alternative.
Please refer to the Schedule of Investments on pages 21–87 for a full listing of Fund securities.
All investments are subject to risk, including the possible loss of principal. In the past several years, financial markets have experienced increased volatility and heightened uncertainty. The market prices of securities may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political, or regulatory conditions, recessions, inflation, changes in interest or currency rates, lack of liquidity in the bond markets, the spread of infectious illness or other public health issues or adverse investor sentiment. These conditions may continue, recur, worsen or spread.
The Fund has the ability to invest in a wide variety of debt securities.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 9

 
The Fund’s investments, payment obligations and financing terms may be based on floating rates, such as LIBOR (London Interbank Offered Rate). Plans are underway to phase out the use of LIBOR. There remains uncertainty regarding the nature of any replacement rate and the impact of the transition from LIBOR on the Fund, issuers of instruments in which the Fund invests, and financial markets generally.
The Fund may invest in underlying funds (including ETFs). In addition to the Fund’s operating expenses, you will indirectly bear the operating expenses of investments in any underlying funds.
The Fund and some of the underlying funds may utilize strategies that have a leveraging effect on the Fund, which increases the volatility of investment returns and subjects the Fund to magnified losses if the Fund’s or an underlying fund’s investments decline in value.
The Fund and some of the underlying funds may use derivatives, such as options and futures, which can be illiquid, may disproportionately increase losses, and have a potentially large impact on Fund performance.
The Fund may invest in inflation-linked securities. As inflationary expectations increase, inflation-linked securities may become more attractive, because they protect future interest payments against inflation. Conversely, as inflationary concerns decrease, inflation-linked securities will become less attractive and less valuable.
The Fund may invest in credit default swaps, which may in some cases be illiquid, and they increase credit risk since the Fund has exposure to both the issuer of the referenced obligation and the counterparty to the credit default swap.
The Fund may invest in subordinated securities which may be disproportionately adversely affected by a default or even a perceived decline in creditworthiness of the issuer.
The Fund may invest in floating rate loans. The value of collateral, if any, securing a floating rate loan can decline or may be insufficient to meet the issuer’s obligations or may be difficult to liquidate.
The Fund may invest in insurance-linked securities. The return of principal and the payment of interest and/or dividends on insurance-linked securities are contingent on the non-occurrence of a pre-defined “trigger” event, such as a hurricane or an earthquake of a specific magnitude.
The Fund may invest in zero-coupon bonds and payment-in-kind securities, which may be more speculative and fluctuate more in value than other fixed income securities. The accrual of income from these securities are payable as taxable annual dividends to shareholders.
Investments in equity securities are subject to price fluctuation.
International investments are subject to special risks including currency fluctuations, social, economic and political uncertainties, which could increase volatility. These risks are magnified in emerging markets.
10 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

Investments in fixed-income securities involve interest rate, credit, inflation, and reinvestment risks. As interest rates rise, the value of fixed income securities generally falls.
The Fund may invest in mortgage-backed securities, which during times of fluctuating interest rates may increase or decrease more than other fixed-income securities. Mortgage-backed securities are also subject to pre-payments.
Prepayment risk is the chance that an issuer may exercise its right to prepay its security, if falling interest rates prompt the issuer to do so. Forced to reinvest the unanticipated proceeds at lower interest rates, the Fund would experience a decline in income and lose the opportunity for additional price appreciation.
High yield bonds possess greater price volatility, illiquidity, and possibility of default.
There may be insufficient or illiquid collateral securing the floating rate loans held within the Fund. This may reduce the future redemption or recovery value of such loans.
The Fund may have disadvantaged access to confidential information that could be used to assess a loan issuer, as Amundi normally seeks to avoid receiving material, non-public information.
The Fund is not a money market fund.
These risks may increase share price volatility.
There is no assurance that these and other strategies used by the Fund or underlying funds will be successful.
Please see the prospectus for a more complete discussion of the Fund’s risks.
Before investing, consider the product’s investment objectives, risks, charges and expenses. Contact your financial professional or Amundi Asset Management US, Inc., for a prospectus or summary prospectus containing this information. Read it carefully.
Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund’s historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 11

 

Portfolio Summary | 3/31/21



   
10 Largest Holdings 
 
(As a percentage of total investments)* 
 
1. 
U.S. Treasury Bills, 4/1/21 
2.49% 
2. 
U.S. Treasury Bills, 4/27/21 
2.04 
3. 
Fannie Mae, 2.5%, 5/1/51 (TBA) 
1.93 
4. 
Fannie Mae, 2.0%, 4/1/51 (TBA) 
1.02 
5. 
Duke Energy Corp., 0.698% (3 Month USD LIBOR + 50 bps), 5/14/21 (144A) 
0.89 
6. 
Fannie Mae, 2.0%, 4/1/36 (TBA) 
0.70 
7. 
PFS Financing Corp., Series 2019-B, Class A, 0.656% (1 Month USD 
 
 
LIBOR + 55 bps), 9/15/23 (144A) 
0.68 
8. 
LSTAR Securities Investment, Ltd., Series 2019-4, Class A1, 1.615% 
 
 
(1 Month USD LIBOR + 150 bps), 5/1/24 (144A) 
0.60 
9. 
Mitsubishi UFJ Financial Group, Inc., 1.008% (3 Month USD 
 
 
LIBOR + 79 bps), 7/25/22 
0.58 
10. 
U.S. Treasury Note, 2.875%, 10/15/21 
0.58 
 
*     
Excludes temporary cash investments and all derivative contracts except for options purchased. The Fund is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any securities.
12 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 
Prices and Distributions | 3/31/21
   
Net Asset Value per Share 
 
Class 3/31/21 3/31/20 
$9.71 $9.26 
$9.71 $9.26 
C2 
$9.72 $9.27 
$9.74 $9.29 
$9.73 $9.27 
 
Distributions per Share: 4/1/20–3/31/21 
 
 
Net Investment Short-Term Long-Term 
Class Income Capital Gains Capital Gains 
$0.1415 $ — $ — 
$0.1120 $ — $ — 
C2 
$0.1124 $ — $ — 
$0.1633 $ — $ — 
$0.1550 $ — $ — 
 
The ICE Bank of America U.S. Dollar 3-Month LIBOR Index is an unmanaged index that tracks the performance of a synthetic asset paying the London Interbank Offered Rate (LIBOR), with a constant 3-month average maturity. The index is based on the assumed purchase at par value of a synthetic instrument having exactly its stated maturity and with a coupon equal to that day’s 3-month LIBOR rate. Index returns assume reinvestment of dividends and, unlike Fund returns, do not reflect any fees, expenses or sales charges. It is not possible to invest directly in an index.
The index defined here pertains to the “Value of $10,000 Investment” and “Value of $5 Million Investment” charts on pages 14–18.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 13

 
  
Performance Update | 3/31/21 
Class A Shares 
 
Investment Returns
The mountain chart on the right shows the change in value of a $10,000 investment made in Class A shares of Pioneer Multi-Asset Ultrashort Income Fund at public offering price during the periods shown, compared to that of the ICE Bank of America (BofA) U.S. Dollar 3-Month LIBOR Index.
Average Annual Total Returns 
 
(As of March 31, 2021) 
 
 
 
 
 
ICE BofA 
 
 
 
U.S. 
 
Net Public Dollar 
 
Asset Offering 3-Month
 
Value Price LIBOR 
Period (NAV) (POP)* Index 
Life-of-Class 
 
 
 
(4/29/11) 
1.40% 1.14% 
0.91% 
5 years 
1.68 1.16 
1.49 
1 year 
6.42 
6.42 
0.64 

Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
 
0.58% 
 
 
 
 
Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
NAV results represent the percent change in net asset value per share.
*POP returns shown above reflect the deduction of the maximum 2.50% front-end sales charge on Class A shares purchased prior to February 5, 2018.
All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.
14 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

  
Performance Update | 3/31/21 
Class C Shares 
 
Investment Returns
The mountain chart on the right shows the change in value of a $10,000 investment made in Class C shares of Pioneer Multi-Asset Ultrashort Income Fund during the periods shown, compared to that of the ICE Bank of America (BofA) U.S. Dollar 3-Month LIBOR Index.
Average Annual Total Returns 
(As of March 31, 2021) 
 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Class 
 
 
(4/29/11) 
1.03% 0.91% 
5 years 
1.37 1.49 
1 year 
6.09 
0.64 

Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.89% 
 
 
 
Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
NAV results represent the percent change in net asset value per share. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 15
 

  
Performance Update | 3/31/21 
Class C2 Shares 
 
Investment Returns
The mountain chart on the right shows the change in value of a $10,000 investment made in Class C2 shares of Pioneer Multi-Asset Ultrashort Income Fund during the periods shown, compared to that of the ICE Bank of America (BofA) U.S. Dollar 3-Month LIBOR Index.
Average Annual Total Returns 
 
(As of March 31, 2021) 
 
 
 
 
 
ICE BofA 
 
 
 
U.S. 
 
 
 
Dollar 
 
 
 
3-Month 
 
If If LIBOR 
Period Held Redeemed Index
Life-of-Fund 
 
 
 
(4/29/11) 
1.04% 1.04% 
0.91% 
5 years 
1.39 1.39 
1.49 
1 year 
6.09 
6.09 
0.64 

Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
 
0.88% 
 
 
 
 
Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
Class C2 shares held for less than 1 year are subject to a 1% contingent deferred sales charge (CDSC). “If Held” results represent the percentage change in net asset value per share. “If Redeemed” returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
The performance shown for periods prior to the commencement of operations of Class C2 shares on August 1, 2013, is the net asset value performance of the Fund’s Class C shares, which has not been restated to reflect any differences in expenses. For the period beginning August 1, 2013, the actual performance of Class C2 shares is reflected.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.
16 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

  
Performance Update | 3/31/21 
Class K Shares 
 
Investment Returns
The mountain chart on the right shows the change in value of a $5 million investment made in Class K shares of Pioneer Multi-Asset Ultrashort Income Fund during the periods shown, compared to that of the ICE Bank of America (BofA) U.S. Dollar 3-Month LIBOR Index.
Average Annual Total Returns 
(As of March 31, 2021) 
 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Fund 
 
 
(4/29/11) 
1.62% 0.91% 
5 years 
1.94 1.49 
1 year 
6.64 
0.64 

Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.36% 
 
 
 
Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
The performance shown for Class K shares for the period prior to the commencement of operations of Class K shares on December 20, 2012, is the net asset value performance of the Fund’s Class A shares, which has not been restated to reflect any differences in expenses, including Rule 12b-1 fees applicable to Class A shares. Since fees for Class A shares generally are higher than those of Class K shares, the performance of Class K shares prior to their inception would have been higher than the performance shown. For the period beginning on December 20, 2012, the actual performance of Class K shares is reflected. Class K shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 17

 

Performance Update | 3/31/21 
Class Y Shares 
 
Investment Returns
The mountain chart on the right shows the change in value of a $5 million investment made in Class Y shares of Pioneer Multi-Asset Ultrashort Income Fund during the periods shown, compared to that of the ICE Bank of America (BofA) U.S. Dollar 3-Month LIBOR Index.
Average Annual Total Returns 
(As of March 31, 2021) 
 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Class 
 
 
(4/29/11) 
1.58% 
0.91% 
5 years 
1.84 
1.49 
1 year 
6.67 
0.64 

Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.44% 
 
 
 
Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
Class Y shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.
18 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
Comparing Ongoing Fund Expenses
As a shareowner in the Fund, you incur two types of costs:
(1)     
ongoing costs, including management fees, distribution and/or service (12b-1) fees, and other Fund expenses; and

(2)     
transaction costs, including sales charges (loads) on purchase payments.
This example is intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 at the beginning of the Fund’s latest six-month period and held throughout the six months.
Using the Tables
Actual Expenses
The first table below provides information about actual account values and actual expenses. You may use the information in this table, together with the amount you invested, to estimate the expenses that you paid over the period as follows:
(1)     
Divide your account value by $1,000
 
Example: an $8,600 account value ÷ $1,000 = 8.6

(2)     
Multiply the result in (1) above by the corresponding share class’s number in the third row under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.
Expenses Paid on a $1,000 Investment in Pioneer Multi-Asset Ultrashort Income Fund
Based on actual returns from October 1, 2020 through March 31, 2021.
Share Class C2 
Beginning Account 
$1,000.00 $1,000.00 $1,000.00 $1,000.00 $1,000.00 
Value on 10/1/20 
     
Ending Account Value 
$1,016.72 $1,014.05 $1,015.02 $1,017.75 $1,017.36 
(after expenses) 
     
on 3/31/21 
     
Expenses Paid 
      $3.02       $4.57       $4.52       $1.86       $2.26 
During Period* 
     
 
*     
Expenses are equal to the Fund’s annualized expense ratio of 0.60%, 0.91%, 0.90%, 0.37% and 0.45% for class A, C, C2, K, and Y respectively, multiplied by the average account value over the period, multiplied by 182/365 (to reflect the partial year period).
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 19

 

Hypothetical Example for Comparison Purposes
The table below provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund’s actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.
You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds.
Please note that the expenses shown in the tables are meant to highlight your ongoing costs only and do not reflect any transaction costs, such as sales charges (loads) that are charged at the time of the transaction. Therefore, the table below is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds. In addition, if these transaction costs were included, your costs would have been higher.
Expenses Paid on a $1,000 Investment in Pioneer Multi-Asset Ultrashort Income Fund
Based on a hypothetical 5% return per year before expenses, reflecting the period from October 1, 2020 through March 31, 2021.
      
Share Class 
A      
C      
C2     
K      
Y      
Beginning Account 
$1,000.00 $1,000.00 $1,000.00 $1,000.00 $1,000.00 
Value on 10/1/20 
     
Ending Account Value 
$1,021.94 $1,020.39 $1,020.44 $1,023.09 $1,022.69 
(after expenses) 
     
on 3/31/21 
     
Expenses Paid 
$3.02 $4.58 $4.53 $1.87 $2.27 
During Period* 
 
 
 
 
 
 
*     
Expenses are equal to the Fund’s annualized expense ratio of 0.60%, 0.91%, 0.90%, 0.37% and 0.45% for class A, C, C2, K, and Y respectively, multiplied by the average account value over the period, multiplied by 182/365 (to reflect the partial year period).
20 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21


Schedule of Investments | 3/31/21
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 UNAFFILIATED ISSUERS — 103.5% 
 

 ASSET BACKED SECURITIES — 25.9%
 
 of Net Assets 
 
1,683,437(a) 321 Henderson Receivables LLC, Series 2005-1A, 
 
 Class A1, 0.336% (1 Month USD LIBOR + 23 bps), 
 
 11/15/40 (144A) $ 1,656,993 
167,153(a) 321 Henderson Receivables I LLC, Series 2004-A, 
 
 Class A1, 0.456% (1 Month USD LIBOR + 
 
 35 bps), 9/15/45 (144A) 164,547 
238,083(a) 321 Henderson Receivables I LLC, Series 2006-1A, 
 
 Class A1, 0.306% (1 Month USD LIBOR + 
 
 20 bps), 3/15/41 (144A) 235,736 
673,936(a) 321 Henderson Receivables I LLC, Series 2006-2A, 
 
 Class A1, 0.306% (1 Month USD LIBOR + 
 
 20 bps), 6/15/41 (144A) 657,124 
937,553(a) 321 Henderson Receivables I LLC, Series 2006-3A, 
 
 Class A1, 0.306% (1 Month USD LIBOR + 
 
 20 bps), 9/15/41 (144A) 914,283 
718,517(a) 321 Henderson Receivables I LLC, Series 2006-4A, 
 
 Class A1, 0.306% (1 Month USD LIBOR + 
 
 20 bps), 12/15/41 (144A) 713,777 
329,909(a) 321 Henderson Receivables I LLC, Series 2007-1A, 
 
 Class A1, 0.306% (1 Month USD LIBOR + 
 
 20 bps), 3/15/42 (144A) 316,843 
1,242,664(a) ABFC Trust, Series 2004-OPT2, Class M1, 0.934% 
 
 (1 Month USD LIBOR + 83 bps), 8/25/33 1,231,313 
5,000,000(a) ABPCI Direct Lending Fund CLO X LP, Series 2020-10A, 
 
 Class A1A, 2.196% (3 Month USD LIBOR + 195 bps), 
 
 1/20/32 (144A) 5,015,905 
3,016,591 ACC Trust, Series 2019-2, Class A, 2.82%, 
 
 2/21/23 (144A) 3,036,605 
153,515(a) ACE Securities Corp. Home Equity Loan Trust, Series 
 
 2005-WF1, Class M2, 0.769% (1 Month USD LIBOR + 
 
 66 bps), 5/25/35 163,574 
491,774(a) ACIS CLO, Ltd., Series 2015-6A, Class A1, 1.795% 
 
 (3 Month USD LIBOR + 159 bps), 5/1/27 (144A) 492,024 
1,946,415(a) Aegis Asset Backed Securities Trust Mortgage 
 
 Pass-Through Ctfs, Series 2004-4, Class M1, 1.009% 
 
 (1 Month USD LIBOR + 90 bps), 10/25/34 1,936,575 
7,100,000(a) Aimco CLO 11, Ltd., Series 2020-11A, Class A1, 1.605% 
 
 (3 Month USD LIBOR + 138 bps), 10/15/31 (144A) 7,112,794 
8,000,000 American Credit Acceptance Receivables Trust, Series 
 
 2020-1, Class B, 2.08%, 12/13/23 (144A) 8,048,981 
2,325,038 American Credit Acceptance Receivables Trust, Series 
 
 2020-2, Class A, 1.65%, 12/13/23 (144A) 2,334,646 
50,668(a) Amortizing Residential Collateral Trust, Series 
 
 2002-BC5, Class M1, 1.144% (1 Month USD LIBOR + 
 
 104 bps), 7/25/32 50,682 
1,320,465 Amur Equipment Finance Receivables V LLC, Series 
 
 
 2018-1A, Class A2, 3.24%, 12/20/23 (144A) 1,324,767 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 21
 

Schedule of Investments | 3/31/21 (continued)
    
Principal 
 
 
Amount 
 
 
USD ($) 
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,328,999  
Amur Equipment Finance Receivables V LLC, Series 
 
  
2018-1A, Class D, 3.98%, 4/22/24 (144A) 
$ 1,341,592 
3,322,585  
Amur Equipment Finance Receivables VI LLC, Series 
 
  
2018-2A, Class A2, 3.89%, 7/20/22 (144A) 
3,369,431 
4,000,000  
Amur Equipment Finance Receivables VII LLC, Series 
 
  
2019-1A, Class B, 2.8%, 3/20/25 (144A) 
4,107,773 
1,857,142(a)  
Apidos CLO XXXII, Series 2019-32A, Class X, 0.874% 
 
  
(3 Month USD LIBOR + 65 bps), 1/20/33 (144A) 
1,857,140 
7,256,167(a)  
Apres Static CLO Ltd., Series 2019-1A, Class A1R, 
 

 1.311% (3 Month USD LIBOR + 107 bps),
  
10/15/28 (144A) 
7,256,487 
9,283,105  
Aqua Finance Trust, Series 2019-A, Class A, 3.14%, 
 
  
7/16/40 (144A) 
9,525,098 
8,337,339  
Aqua Finance Trust, Series 2020-AA, Class A, 1.9%, 
 
  
7/17/46 (144A) 
8,415,717 
4,000,000(a)  
Ares LVII CLO Ltd., Series 2020-57A, Class X, 0.994% 
 
  
(3 Month USD LIBOR + 75 bps), 10/25/31 (144A) 
3,999,988 
3,235,159(a)  
Argent Securities, Inc. Asset-Backed Pass-Through 
 
  Certificates, Series 2003-W4, Class M1, 1.309% 
  
(1 Month USD LIBOR + 120 bps), 10/25/33 
3,224,466 
607,403(a)  
Argent Securities, Inc. Asset-Backed Pass-Through 
 
  
Certificates, Series 2004-W11, Class M2, 1.159% 
 
  
(1 Month USD LIBOR + 105 bps), 11/25/34 
609,015 
42,755(a)  
Argent Securities, Inc. Asset-Backed Pass-Through 
 
  
Certificates, Series 2005-W3, Class A2D, 0.789% 
 
  
(1 Month USD LIBOR + 68 bps), 11/25/35 
42,702 
4,234,279  
Arivo Acceptance Auto Loan Receivables Trust, 
 
  
Series 2019-1, Class A, 2.99%, 7/15/24 (144A) 
4,286,525 
2,568,901(a)  
Asset Backed Securities Corp. Home Equity Loan 
 
  
Trust, Series 2003-HE3, Class M1, 1.351% (1 Month 
 
  
USD LIBOR + 125 bps), 6/15/33 
2,584,524 
5,792(a)  
Asset-Backed Pass-Through Certificates, Series 
 
  
2004-R2, Class A1A, 0.799% (1 Month USD LIBOR + 
 
  
69 bps), 4/25/34 
5,790 
60,983(a)  
Asset-Backed Pass-Through Certificates, Series 
 
  
2004-R2, Class A1B, 0.729% (1 Month USD LIBOR + 
 
  
62 bps), 4/25/34 
60,962 
11,863,334(a)  
Atlas Senior Loan Fund III, Ltd., Series 2013-1A, 
 
  
Class AR, 1.022% (3 Month USD LIBOR + 83 bps), 
 
  
11/17/27 (144A) 
11,864,698 
526,346(a)  
Atlas Senior Loan Fund XII, Ltd., Series 2018-12A, 
 
  
Class X, 0.968% (3 Month USD LIBOR + 75 bps), 
 
  
10/24/31 (144A) 
526,328 
700,120  
Avant Loans Funding Trust, Series 2019-B, Class A, 
 
  
2.72%, 10/15/26 (144A) 
701,268 
2,678,638  
Avid Automobile Receivables Trust, Series 2019-1, 
 
  
Class A, 2.62%, 2/15/24 (144A) 
2,698,711 
6,250,000(a)  
Barings Middle Market CLO, Ltd., Series 2018-IA, 
 
  
Class A1, 1.771% (3 Month USD LIBOR + 
 
  
153 bps), 1/15/31 (144A) 
6,250,556 
 
 The accompanying notes are an integral part of these financial statements.
22 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
750,000(a)  
Battery Park CLO, Ltd., Series 2019-1A, Class X, 0.891% 
 
 
 
(3 Month USD LIBOR + 65 bps), 7/15/32 (144A) 
$ 749,999 
2,500,000(a)  
BDS, Ltd., Series 2020-FL5, Class C, 2.158% (1 Month 
 
 
 
USD LIBOR + 205 bps), 2/16/37 (144A) 
2,496,882 
859,375(a)  
Bean Creek CLO, Ltd., Series 2015-1A, Class XR, 0.824% 
 
 
 
(3 Month USD LIBOR + 60 bps), 4/20/31 (144A) 
859,359 
279,595(a)  
Bear Stearns Asset Backed Securities Trust, Series 
 
 
 
2001-3, Class A1, 1.009% (1 Month USD LIBOR + 
 
 
 
90 bps), 10/27/32 
274,686 
2,000,000(a)  
Brightwood Capital MM CLO Ltd., Series 2020-1A, 
 
 
 
Class D, 5.584% (3 Month USD LIBOR + 540 bps), 
 
 
 
12/15/28 (144A) 
2,021,834 
656,688  
BXG Receivables Note Trust, Series 2020-A, Class B, 
 
 
 
2.49%, 2/28/36 (144A) 
660,619 
1,750,000(a)  
California Street CLO IX LP, Series 2012-9A, 
 
 
 
Class XR2, 0.923% (3 Month USD LIBOR + 70 bps), 
 
 
 
7/16/32 (144A) 
1,749,953 
166,120(a)  
Carlyle US CLO, Ltd., Series 2019-4A, Class M, 0.891% 
 
 
 
(3 Month USD LIBOR + 65 bps), 1/15/33 (144A) 
166,118 
3,321,624  
Carnow Auto Receivables Trust, Series 2019-1A, 
 
 
 
Class A, 2.72%, 11/15/22 (144A) 
3,334,186 
5,000,000  
Carvana Auto Receivables Trust, Series 2020-N1A, 
 
 
 
Class D, 3.43%, 1/15/26 (144A) 
5,209,441 
417,108  
Cazenovia Creek Funding II LLC, Series 2018-1A, 
 
 
 
Class B, 3.984%, 7/15/30 (144A) 
415,172 
5,000,000(a)  
CBAM, Ltd., Series 2017-3A, Class A, 1.453% 
 
 
 
(3 Month USD LIBOR + 123 bps), 10/17/29 (144A) 
5,001,680 
7,179(b)  
Centex Home Equity Loan Trust, Series 2003-A, 
 
 
 
Class AF6, 3.654%, 3/25/33 
7,194 
1,500,000(a)  
Cerberus Loan Funding XXVIII LP, Series 2020-1A, 
 
 
 
Class A, 2.091% (3 Month USD LIBOR + 
 
 
 
185 bps), 10/15/31 (144A) 
1,504,424 
4,417,102(b)  
CFMT LLC, Series 2020-HB3, Class A, 2.812%, 
 
 
 
5/25/30 (144A) 
4,457,945 
4,737,064  
Chase Auto Credit Linked Notes, Series 2020-1, 
 
 
 
Class B, 0.991%, 1/25/28 (144A) 
4,749,985 
9,000,000  
Chase Auto Credit Linked Notes, Series 2021-1, 
 
 
 
Class B, 0.875%, 9/25/28 (144A) 
8,997,760 
2,068,000  
Chase Auto Credit Linked Notes, Series 2021-1, 
 
 
 
Class C, 1.024%, 9/25/28 (144A) 
2,067,465 
4,000,000  
Chase Auto Credit Linked Notes, Series 2021-1, 
 
 
 
Class F, 4.28%, 9/25/28 (144A) 
3,987,486 
147,736(a)  
Chesapeake Funding II LLC, Series 2017-3A, 
 
 
 
Class A2, 0.446% (1 Month USD LIBOR + 34 bps), 
 
 
 
8/15/29 (144A) 
147,739 
1,902,505(a)  
Chesapeake Funding II LLC, Series 2018-1A, 
 
 
 
Class A2, 0.556% (1 Month USD LIBOR + 45 bps), 
 
 
 
4/15/30 (144A) 
1,902,950 
16,865,000(a)  
CIFC Funding Ltd., Series 2015-3A, Class AR, 1.093% 
 
 
 
(3 Month USD LIBOR + 87 bps), 4/19/29 (144A) 
16,845,285 
 

 
 

The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 23
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,159,846  
CIG Auto Receivables Trust, Series 2019-1A, Class A, 
 
  
3.33%, 8/15/24 (144A) 
$ 2,172,691 
1,914,121  
CIG Auto Receivables Trust, Series 2020-1A, Class A, 
 
  
0.68%, 10/12/23 (144A) 
1,916,098 
2,033,190(a)  
CIM Small Business Loan Trust, Series 2018-1A, 
 
  
Class A, 1.511% (1 Month USD LIBOR + 140 bps), 
 
  
3/20/43 (144A) 
2,011,648 
10,000,000(a)  
Citibank Credit Card Issuance Trust, Series 2017-A7, 
 
  
Class A7, 0.474% (1 Month USD LIBOR + 
 
  
37 bps), 8/8/24 
10,041,058 
515,000(a)  
Citibank Credit Card Issuance Trust, Series 2018-A4, 
 
  
Class A4, 0.444% (1 Month USD LIBOR + 
 
  
34 bps), 6/7/25 
516,365 
457,137(a)  
Citigroup Mortgage Loan Trust, Inc., Series 
 
  
2006-WFH1, Class M3, 0.709% (1 Month USD LIBOR + 
 
  
60 bps), 1/25/36 
457,033 
187,500(a)  
Clear Creek CLO, Series 2015-1A, Class X, 1.224% 
 
  
(3 Month USD LIBOR + 100 bps), 10/20/30 (144A) 
187,495 
966,295  
Commonbond Student Loan Trust, Series 2016-B, 
 
  
Class A1, 2.73%, 10/25/40 (144A) 
982,267 
173,971(a)  
Commonbond Student Loan Trust, Series 2016-B, 
 
  
Class A2, 1.559% (1 Month USD LIBOR + 145 bps), 
 
  
10/25/40 (144A) 
175,011 
1,594,820(a)  
Commonbond Student Loan Trust, Series 2017-AGS, 
 
  
Class A2, 0.959% (1 Month USD LIBOR + 
 
  
85 bps), 5/25/41 (144A) 
1,594,311 
2,905,655(a)  
Commonbond Student Loan Trust, Series 2017-BGS, 
 
  
Class A2, 0.759% (1 Month USD LIBOR + 
 
  
65 bps), 9/25/42 (144A) 
2,889,215 
2,397,053(a)  
Commonbond Student Loan Trust, Series 2018-AGS, 
 
  
Class A2, 0.609% (1 Month USD LIBOR + 
 
  
50 bps), 2/25/44 (144A) 
2,380,763 
4,877,412(a)  
Commonbond Student Loan Trust, Series 2018-BGS, 
 
  
Class A2, 0.679% (1 Month USD LIBOR + 
 
  
57 bps), 9/25/45 (144A) 
4,845,661 
3,216,380(a)  
Commonbond Student Loan Trust, Series 2018-CGS, 
 
  
Class A2, 0.909% (1 Month USD LIBOR + 
 
  
80 bps), 2/25/46 (144A) 
3,184,020 
5,966,961(a)  
Commonbond Student Loan Trust, Series 2019-AGS, 
 
  
Class A2, 1.009% (1 Month USD LIBOR + 
 
  
90 bps), 1/25/47 (144A) 
5,984,510 
515,188  
Conn’s Receivables Funding LLC, Series 2019-A, 
 
  
Class A, 3.4%, 10/16/23 (144A) 
517,726 
1,519,590  
Conn’s Receivables Funding LLC, Series 2019-A, 
 
  
Class B, 4.36%, 10/16/23 (144A) 
1,526,130 
2,986,147  
Conn’s Receivables Funding LLC, Series 2020-A, 
 
  
Class A, 1.71%, 6/16/25 (144A) 
2,995,957 
4,250,000  
Conn’s Receivables Funding LLC, Series 2020-A, 
 
  
Class C, 4.2%, 6/16/25 (144A) 
4,266,309 
 
The accompanying notes are an integral part of these financial statements.
24 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
33,998(a)  
Conseco Finance Home Equity Loan Trust, Series 
 
  
2002-C, Class MV1, 1.606% (1 Month USD LIBOR + 
 
  
150 bps), 5/15/32 
$ 34,040 
207,754  
Consumer Lending Receivables Trust, Series 2019-A, 
 
  
Class A, 3.52%, 4/15/26 (144A) 
207,956 
11,783,637  
Consumer Loan Underlying Bond Club Certificate 
 

 Issuer Trust, Series 2019-HP1, Class A, 2.59%, 
  
12/15/26 (144A) 
11,913,609 
3,619,855  
Consumer Loan Underlying Bond CLUB Credit Trust, 
 
  
Series 2020-P1, Class A, 2.26%, 3/15/28 (144A) 
3,642,759 
856,156  
Consumer Loan Underlying Bond Credit Trust, Series 
 
  
2019-P1, Class A, 2.94%, 7/15/26 (144A) 
859,263 
19,217(a)  
Countrywide Asset-Backed Certificates, Series 
 
  
2005-9, Class M1, 0.889% (1 Month USD LIBOR + 
 
  
78 bps), 1/25/36 
19,216 
1,930,924(a)  
Countrywide Asset-Backed Certificates, Series 
 
  
2006-4, Class 2A3, 0.689% (1 Month USD LIBOR + 
 
  
58 bps), 7/25/36 
1,929,552 
5,000,000  
Credit Acceptance Auto Loan Trust, Series 2020-1A, 
 
  
Class C, 2.59%, 6/15/29 (144A) 
5,153,514 
864,076(a)  
Credit Suisse Seasoned Loan Trust, Series 2006-1, 
 
  Class A, 0.349% (1 Month USD LIBOR + 24 bps),
 
  
10/25/34 (144A) 
863,817 
1,350,000  
Crossroads Asset Trust, Series 2021-A, Class B, 1.12%, 
 
  
6/20/25 (144A) 
1,347,095 
500,000  
Crossroads Asset Trust, Series 2021-A, Class D, 2.52%, 
 
  
1/20/26 (144A) 
497,725 
813,257(a)  
CWHEQ Revolving Home Equity Loan Resuritization 
 
  
Trust, Series 2006-RES, Class 4M1A, 0.386% (1 Month 
 
  
USD LIBOR + 28 bps), 2/15/34 (144A) 
807,682 
1,564,275(a)  
CWHEQ Revolving Home Equity Loan Resuritization 
 
  
Trust, Series 2006-RES, Class 4N1A, 0.386% (1 Month 
 
  
USD LIBOR + 28 bps), 2/15/34 (144A) 
1,546,595 
33,336  
Dell Equipment Finance Trust, Series 2018-2, 
 
  
Class A3, 3.37%, 10/22/23 (144A) 
33,430 
1,463,609  
Dell Equipment Finance Trust, Series 2020-1, 
 
  
Class A2, 2.26%, 6/22/22 (144A) 
1,476,349 
90  
Delta Funding Home Equity Loan Trust, Series 
 
  
1997-2, Class A6, 7.04%, 6/25/27 
82 
827,777  
DLL LLC, Series 2018-ST2, Class A3, 3.46%, 
 
  
1/20/22 (144A) 
829,081 
383,393(a)  
DRB Prime Student Loan Trust, Series 2015-D, 
 
  
Class A1, 1.809% (1 Month USD LIBOR + 170 bps), 
 
  
1/25/40 (144A) 
384,070 
189,389(a)  
DRB Prime Student Loan Trust, Series 2016-B, 
 
  
Class A1, 1.909% (1 Month USD LIBOR + 180 bps), 
 
  
6/25/40 (144A) 
190,698 
1,120,738(a)  
DRB Prime Student Loan Trust, Series 2017-A, 
 
  
Class A1, 0.959% (1 Month USD LIBOR + 85 bps), 
 
  
5/27/42 (144A) 
1,121,315 
 The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 25
 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
741,332  
Drive Auto Receivables Trust, Series 2020-2, 
 
 
 
Class A2A, 0.85%, 7/17/23 
$ 742,394 
722,786(a)  
Drug Royalty III LP 1, Series 2017-1A, Class A1, 2.741% 
 
 
 
(3 Month USD LIBOR + 250 bps), 4/15/27 (144A) 
722,781 
1,638,819(a)  
Drug Royalty III LP 1, Series 2018-1A, Class A1, 1.841% 
 
 
 
(3 Month USD LIBOR + 160 bps), 10/15/31 (144A) 
1,620,699 
1,218,750(a)  
Dryden 80 CLO, Ltd., Series 2019-80A, Class X, 1.123% 
 
 
 
(3 Month USD LIBOR + 90 bps), 1/17/33 (144A) 
1,218,748 
205,342(a)  
Earnest Student Loan Program LLC, Series 2016-C, 
 
 
 
Class A1, 1.959% (1 Month USD LIBOR + 185 bps), 
 
 
 
10/27/36 (144A) 
205,492 
203,710(a)  
Earnest Student Loan Program LLC, Series 2016-D, 
 
 
 
Class A1, 1.509% (1 Month USD LIBOR + 140 bps), 
 
 
 
1/25/41 (144A) 
203,886 
634,395(a)  
Earnest Student Loan Program LLC, Series 2017-A, 
 
 
 
Class A1, 1.109% (1 Month USD LIBOR + 100 bps), 
 
 
 
1/25/41 (144A) 
635,797 
1,750,000(a)  
Elmwood CLO IV, Ltd., Series 2020-1A, Class X, 0.941% 
 
 
 
(3 Month USD LIBOR + 70 bps), 4/15/33 (144A) 
1,729,532 
1,110,615  
FCI Funding LLC, Series 2019-1A, Class A, 3.63%, 
 
 
 
2/18/31 (144A) 
1,127,010 
7,487,736  
FHF Trust, Series 2020-1A, Class A, 2.59%, 
 
 
 
12/15/23 (144A) 
7,544,343 
7,500,000  
FHF Trust, Series 2021-1A, Class A, 1.27%, 
 
 
 
3/15/27 (144A) 
7,497,644 
3,985,065(a)  
Fieldstone Mortgage Investment Trust, Series 2005-3, 
 
 
 
Class 2A3, 0.789% (1 Month USD LIBOR + 
 
 
 
68 bps), 2/25/36 
3,962,443 
2,500,000(b)  
Finance of America HECM Buyout, Series 2021-HB1, 
 
 
 
Class M3, 3.64%, 2/25/31 (144A) 
2,482,615 
29,052(a)  
First Franklin Mortgage Loan Trust, Series 2004-FF4, 
 
 
 
Class M1, 0.964% (1 Month USD LIBOR + 
 
 
 
86 bps), 6/25/34 
29,046 
41,659(a)  
First Franklin Mortgage Loan Trust, Series 2005-FFH2, 
 
 
 
Class M2, 0.919% (1 Month USD LIBOR + 
 
 
 
81 bps), 4/25/35 (144A) 
41,663 
1,300,991  
First Investors Auto Owner Trust, Series 2019-1A, 
 
 
 
Class A, 2.89%, 3/15/24 (144A) 
1,310,859 
10,184,708(a)  
Fort CRE LLC, Series 2018-1A, Class A1, 1.458% 
 
 
 
(1 Month USD LIBOR + 135 bps), 11/16/35 (144A) 
10,190,341 
500,000(a)  
Fort Washington CLO, Series 2019-1A, Class A, 
 
 
 
1.644% (3 Month USD LIBOR + 142 bps), 
 
 
 
10/20/32 (144A) 
500,784 
2,750,000(a)  
Fortress Credit Opportunities VI CLO, Ltd., Series 
 
 
 
2015-6A, Class A1TR, 1.585% (3 Month USD LIBOR + 
 
 
 
136 bps), 7/10/30 (144A) 
2,729,455 
4,113,000(a)  
Fortress Credit Opportunities IX CLO, Ltd., Series 
 
 
 
2017-9A, Class A1T, 1.744% (3 Month USD LIBOR + 
 
 
 
155 bps), 11/15/29 (144A) 
4,112,256 
 The accompanying notes are an integral part of these financial statements.
26 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued)
 
2,491,695(a)  
Fortress Credit Opportunities XIII CLO, Ltd., Series 
 
  
2020-13A, Class A, 2.491% (3 Month USD LIBOR + 
 
  
225 bps), 7/15/28 (144A) 
$ 2,498,440 
11,000,000  
Foundation Finance Trust, Series 2021-1A, Class A, 
 
  
1.27%, 5/15/41 (144A) 
10,936,030 
319,404  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2019-1, Class A2, 2.58%, 3/15/23 (144A) 
319,621 
2,874,220  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2020-1, Class A2, 1.97%, 9/15/23 (144A) 
2,888,213 
2,500,000  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2020-1, Class B, 2.27%, 2/18/25 (144A) 
2,553,545 
1,480,051  
Freed ABS Trust, Series 2020-2CP, Class A, 4.52%, 
 
  
6/18/27 (144A) 
1,492,616 
2,662,294  
Freed ABS Trust, Series 2020-FP1, Class A, 2.52%, 
 
  
3/18/27 (144A) 
2,680,333 
1,300,000  
Freed ABS Trust, Series 2021-1CP, Class C, 2.83%, 
 
  
3/20/28 (144A) 
1,298,102 
501,963(a)  
Fremont Home Loan Trust, Series 2005-E, Class 1A1, 
 
  
0.569% (1 Month USD LIBOR + 46 bps), 1/25/36 
501,847 
2,596,819(a)  
Fremont Home Loan Trust, Series 2006-2, Class 1A1, 
 
  
0.429% (1 Month USD LIBOR + 32 bps), 2/25/36 
2,584,303 
2,862,355  
Genesis Private Label Amortizing Trust, Series 2020-1, 
 
  
Class A, 2.08%, 7/20/30 (144A) 
2,865,986 
49,432  
GLS Auto Receivables Issuer Trust, Series 2019-1A, 
 
  
Class A, 3.37%, 1/17/23 (144A) 
49,485 
3,000,000  
GLS Auto Receivables Issuer Trust, Series 2019-3A, 
 
  
Class B, 2.72%, 6/17/24 (144A) 
3,062,649 
673,250  
GLS Auto Receivables Trust, Series 2018-1A, Class B, 
 
  
3.52%, 8/15/23 (144A) 
681,131 
2,054,351  
Gold Key Resorts LLC, Series 2014-A, Class B, 3.72%, 
 
  
3/17/31 (144A) 
2,081,044 
466,667(a)  
Goldentree Loan Management US CLO 5, Ltd., 
 
  
Series 2019-5A, Class X, 0.724% (3 Month USD LIBOR + 
 
  
50 bps), 10/20/32 (144A) 
466,666 
700,000(a)  
Goldentree Loan Management US CLO 8, Ltd., Series 
 
  
2020-8A, Class X, 1.074% (3 Month USD LIBOR + 
 
  
85 bps), 7/20/31 (144A) 
699,999 
3,000,000(a)  
Golub Capital Partners CLO 24M-R, Ltd., Series 
 
  
2015-24A, Class AR, 1.795% (3 Month USD LIBOR + 
 
  
160 bps), 11/5/29 (144A) 
3,000,831 
1,821,000(a)  
Golub Capital Partners CLO 25M, Ltd., Series 
 
  
2015-25A, Class AR, 1.575% (3 Month USD LIBOR + 
 
  
138 bps), 5/5/30 (144A) 
1,821,117 
10,000,000(b)  
Golub Capital Partners CLO 34M, Ltd., Series 
 
  
2017-34A, Class AR, 14/3/31 (144A) 
10,000,000 
5,000,000(a)  
Golub Capital Partners CLO 46M, Ltd., Series 
 
  
2019-46A, Class A1A, 2.024% (3 Month USD LIBOR + 
 
  
180 bps), 4/20/32 (144A) 
5,017,860 
 The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 27
 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued)
 
2,499,902(a)  
Gracie Point International Funding, Series 2020-B, 
 
  
Class A, 1.515% (1 Month USD LIBOR + 
 
  
140 bps), 5/2/23 (144A) 
$ 2,503,716 
3,000,000(a)  
Gracie Point International Funding, Series 2020-B, 
 
  
Class B, 2.515% (1 Month USD LIBOR + 240 bps), 
 
  
5/2/23 (144A) 
3,004,454 
1,305,556(a)  
Greywolf CLO III, Ltd., Series 2020-3RA, Class XR, 
 
  
0.722% (3 Month USD LIBOR + 50 bps), 
 
  
4/15/33 (144A) 
1,297,810 
3,669,663(a)  
HANA SBA Loan Trust, Series 2019-1, Class A, 2.13% 
 
  
(1 Month USD LIBOR + 200 bps), 8/25/45 (144A) 
3,643,051 
666,667(a)  
Harbor Park CLO, Ltd., Series 2018-1A, Class X, 
 
  
1.124% (3 Month USD LIBOR + 90 bps), 
 
  
1/20/31 (144A) 
666,665 
252,937(a)  
Hertz Fleet Lease Funding LP, Series 2017-1, 
 
  
Class A1, 0.756% (1 Month USD LIBOR + 65 bps), 
 
  
4/10/31 (144A) 
253,057 
2,095,947(a)  
Hertz Fleet Lease Funding LP, Series 2018-1, 
 
  
Class A1, 0.606% (1 Month USD LIBOR + 50 bps), 
 
  
5/10/32 (144A) 
2,096,143 
182,048(a)  
Hertz Fleet Lease Funding LP, Series 2019-1, 
 
  
Class A1, 0.576% (1 Month USD LIBOR + 47 bps), 
 
  
1/10/33 (144A) 
182,438 
4,000,000  
HOA Funding LLC, Series 2015-1A, Class B, 9.0%, 
 
  
8/20/44 (144A) 
3,855,320 
40,337(a)  
Home Equity Asset Trust, Series 2004-8, Class M1, 
 
  
0.979% (1 Month USD LIBOR + 87 bps), 3/25/35 
40,354 
1,234,610(a)  
Home Equity Asset Trust, Series 2005-3, Class M4, 
 
  
1.069% (1 Month USD LIBOR + 96 bps), 8/25/35 
1,235,428 
49,740(a)  
Home Equity Asset Trust, Series 2005-7, Class M1, 
 
  
0.784% (1 Month USD LIBOR + 68 bps), 1/25/36 
49,684 
3,000,000(a)  
Home Partners of America Trust, Series 2017-1, 
 
  
Class C, 1.658% (1 Month USD LIBOR + 155 bps), 
 
  
7/17/34 (144A) 
2,999,999 
2,500,000(a)  
Home Partners of America Trust, Series 2017-1, 
 
  
Class D, 2.008% (1 Month USD LIBOR + 190 bps), 
 
  
7/17/34 (144A) 
2,497,166 
2,000,000(a)  
Home Partners of America Trust, Series 2018-1, 
 
  
Class C, 1.358% (1 Month USD LIBOR + 125 bps), 
 
  
7/17/37 (144A) 
2,003,098 
1,287,879  
HPEFS Equipment Trust, Series 2019-1A, Class A2, 
 
  
2.19%, 9/20/29 (144A) 
1,289,532 
2,067,000(a)  
Invitation Homes Trust, Series 2017-SFR2, Class C, 
 

 1.558% (1 Month USD LIBOR + 145 bps),
 
  
12/17/36 (144A) 
2,070,764 
10,734,949(a)  
Invitation Homes Trust, Series 2018-SFR1, Class A, 
 
  
0.808% (1 Month USD LIBOR + 70 bps), 
 
  
3/17/37 (144A) 
10,751,661 
4,000,000(a)  
Invitation Homes Trust, Series 2018-SFR1, Class B, 
 
  
1.058% (1 Month USD LIBOR + 95 bps), 
 
  
3/17/37 (144A) 
3,994,206 

 The accompanying notes are an integral part of these financial statements.
28 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued)
 
7,162,394(a)  
Invitation Homes Trust, Series 2018-SFR1, Class D, 
 
 
 
1.558% (1 Month USD LIBOR + 145 bps), 
 
 
 
3/17/37 (144A) 
$ 7,174,737 
1,750,000(a)  
Invitation Homes Trust, Series 2018-SFR2, Class C, 
 
 
 
1.386% (1 Month USD LIBOR + 128 bps), 
 
 
 
6/17/37 (144A) 
1,754,614 
9,998,014(a)  
Invitation Homes Trust, Series 2018-SFR2, Class D, 
 
 
 
1.556% (1 Month USD LIBOR + 145 bps), 
 
 
 
6/17/37 (144A) 
10,006,198 
4,086,655(a)  
Invitation Homes Trust, Series 2018-SFR3, Class E, 
 
 
 
2.108% (1 Month USD LIBOR + 200 bps), 
 
 
 
7/17/37 (144A) 
4,086,652 
13,816,167(a)  
Invitation Homes Trust, Series 2018-SFR4, Class E, 
 
 
 
2.058% (1 Month USD LIBOR + 195 bps), 
 
 
 
1/17/38 (144A) 
13,816,156 
5,900,000(a)  
Ivy Hill Middle Market Credit Fund X, Ltd., Series 10A, 
 
 
 
Class A1AR, 1.473% (3 Month USD LIBOR + 125 bps), 
 
 
 
7/18/30 (144A) 
5,898,667 
372,975(a)  
KVK CLO, Ltd., Series 2018-1A, Class A, 1.112% 
 
 
 
(3 Month USD LIBOR + 93 bps), 5/20/29 (144A) 
372,371 
15,000,000(a)  
KVK CLO, Ltd., Series 2018-1A, Class B, 1.832% 
 
 
 
(3 Month USD LIBOR + 165 bps), 5/20/29 (144A) 
15,004,500 
5,500,000(a)  
Lake Shore MM CLO III LLC, Series 2020-1A, Class A, 
 
 
 
2.529% (3 Month USD LIBOR + 230 bps), 
 
 
 
10/15/29 (144A) 
5,531,240 
3,255,853(a)  
Laurel Road Prime Student Loan Trust, Series 2017-C, 
 
 
 
Class A1, 0.659% (1 Month USD LIBOR + 55 bps), 
 
 
 
11/25/42 (144A) 
3,245,177 
671,053  
Laurel Road Prime Student Loan Trust, Series 2020-A, 
 
 
 
Class A1FX, 0.72%, 11/25/50 (144A) 
671,389 
300,000(a)  
LCM 28, Ltd., Series 28A, Class X, 1.124% (3 Month 
 
 
 
USD LIBOR + 90 bps), 10/20/30 (144A) 
299,995 
8,000,000(a)  
LCM XVIII LP, Series 18A, Class A1R, 1.244% (3 Month 
 
 
 
USD LIBOR + 102 bps), 4/20/31 (144A) 
7,978,944 
421,269(a)  
Lehman XS Trust, Series 2005-4, Class 1A3, 0.909% 
 
 
 
(1 Month USD LIBOR + 80 bps), 10/25/35 
421,685 
279,627  
Lendingpoint Asset Securitization Trust, Series 2019-1, 
 
 
 
Class B, 3.613%, 8/15/25 (144A) 
279,799 
215,775  
Lendingpoint Asset Securitization Trust, Series 2020-1, 
 
 
 
Class A, 2.512%, 2/10/26 (144A) 
215,839 
8,684,000  
Lendingpoint Asset Securitization Trust, Series 2020-1, 
 
 
 
Class C, 4.143%, 2/10/26 (144A) 
8,796,616 
10,000,000+  
LFS 2021A LLC, Series 2021-A, Class A, 2.46%, 
 
 
 
4/15/33 (144A) 
10,000,000 
2,161,696  
LL ABS Trust, Series 2019-1A, Class A, 2.87%, 
 
 
 
3/15/27 (144A) 
2,167,644 
3,352,261  
LL ABS Trust, Series 2020-1A, Class A, 2.33%, 
 
 
 
1/17/28 (144A) 
3,376,530 
7,500,000(a)  
LoanCore Issuer, Ltd., Series 2019-CRE2, Class A, 
 
 
 
1.236% (1 Month USD LIBOR + 113 bps), 
 
 
 
5/15/36 (144A) 
7,499,998 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 29
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued)
 
8,300,000(a)  
M360 LLC, Series 2019-CRE2, Class A, 1.506% 
 
  
(1 Month USD LIBOR + 140 bps), 9/15/34 (144A) 
$ 8,299,997 
1,000,000(a)  
Madison Park Funding XII, Ltd., Series 2014-12A, 
 
 ��
Class CR, 2.574% (3 Month USD LIBOR + 
 
  
235 bps), 7/20/26 (144A) 
1,000,411 
3,070,000(a)  
Madison Park Funding XV, Ltd., Series 2014-15A, 
 
  
Class A2R, 1.713% (3 Month USD LIBOR + 
 
  
150 bps), 1/27/26 (144A) 
3,070,933 
250,000(a)  
Magnetite VII, Ltd., Series 2012-7A, Class A1R2, 
 
  
1.041% (3 Month USD LIBOR + 80 bps), 
 
  
1/15/28 (144A) 
250,034 
8,629,000(a)  
Magnetite XVIII, Ltd., Series 2016-18A, Class AR, 
 
  
1.274% (3 Month USD LIBOR + 108 bps), 
 
  
11/15/28 (144A) 
8,631,451 
327,303  
Marlette Funding Trust, Series 2017-1A, Class C, 
 
  
6.658%, 3/15/24 (144A) 
327,546 
2,623,603  
Marlette Funding Trust, Series 2020-1A, Class A, 
 
  
2.24%, 3/15/30 (144A) 
2,633,544 
5,250,000  
Mercury Financial Credit Card Master Trust, Series 
 
  
2021-1A, Class A, 1.54%, 3/20/26 (144A) 
5,250,244 
210,184(a)  
Merrill Lynch Mortgage Investors Trust, Series 
 
  
2004-OPT1, Class A1B, 0.969% (1 Month USD LIBOR + 
 
  
86 bps), 6/25/35 
209,109 
1,195,274(a)  
Merrill Lynch Mortgage Investors Trust, Series 
 
  
2005-AR1, Class M1, 0.859% (1 Month USD LIBOR + 
 
  
75 bps), 6/25/36 
1,194,411 
9,000,000(a)  
MF1, Ltd., Series 2020-FL4, Class A, 1.806% (1 Month 
 
  
USD LIBOR + 170 bps), 11/15/35 (144A) 
9,064,224 
3,179,468  
MMAF Equipment Finance LLC, Series 2019-B, 
 
  
Class A2, 2.07%, 10/12/22 (144A) 
3,200,760 
4,750,000(a)  
Monroe Capital Bsl CLO, Ltd., Series 2015-1A, 
 
  
Class CR, 2.632% (3 Month USD LIBOR + 245 bps), 
 
  
5/22/27 (144A) 
4,750,019 
4,500,000(a)  
Monroe Capital Mml CLO, Ltd., Series 2017-1A, 
 
  
Class A, 1.822% (3 Month USD LIBOR + 160 bps), 
 
  
4/22/29 (144A) 
4,500,918 
1,410,514(a)  
Morgan Stanley Capital I, Inc. Trust, Series 2006-NC2, 
 
  
Class A2D, 0.689% (1 Month USD LIBOR + 
 
  
58 bps), 2/25/36 
1,401,321 
3,696,945(a)  
Morgan Stanley Dean Witter Capital I, Inc. Trust, Series 
 
  
2002-NC4, Class M1, 1.384% (1 Month USD LIBOR + 
 
  
128 bps), 9/25/32 
3,693,788 
436,132(a)  
Morgan Stanley Home Equity Loan Trust, Series 
 
  
2006-2, Class A4, 0.669% (1 Month USD LIBOR + 
 
  
56 bps), 2/25/36 
432,464 
2,211,232(a)  
National Collegiate Trust, Series 2007-A, Class A, 
 
  
0.404% (1 Month USD LIBOR + 30 bps), 
 
  
5/25/31 (144A) 
2,171,342 
3,688,084(b)  
Nationstar HECM Loan Trust, Series 2019-1A, Class A, 
 
  
2.651%, 6/25/29 (144A) 
3,693,950 
 
The accompanying notes are an integral part of these financial statements.
30 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued)
 
3,560,356(b)  
Nationstar HECM Loan Trust, Series 2020-1A, 
 
  
Class A1, 1.269%, 9/25/30 (144A) 
$ 3,566,511 
4,089,127(a)  
Nationstar Home Equity Loan Trust, Series 2006-B, 
 
  
Class AV4, 0.389% (1 Month USD LIBOR + 
 
  
28 bps), 9/25/36 
4,078,095 
5,000,000(a)  
Navient Student Loan Trust, Series 2021-1A, 
 
  
Class A1B, 0.762% (1 Month USD LIBOR + 60 bps), 
 
  
12/26/69 (144A) 
5,014,682 
4,000,000(a)  
Navistar Financial Dealer Note Master Trust, 
 

 Series 2020-1, Class A, 1.059% (1 Month USD
 
  
LIBOR + 95 bps), 7/25/25 (144A) 
4,028,246 
1,000,000(a)  
Navistar Financial Dealer Note Master Trust, 
 
  
Series 2020-1, Class C, 2.259% (1 Month USD LIBOR + 
 
  
215 bps), 7/25/25 (144A) 
1,012,753 
1,498,642  
Nelnet Private Education Loan Trust, Series 2016-A, 
 
  
Class A1B, 3.6%, 12/26/40 (144A) 
1,525,606 
7,624,262(a)  
Nelnet Student Loan Trust, Series 2005-2, Class A5, 
 
  
0.287% (3 Month USD LIBOR + 10 bps), 3/23/37 
7,424,849 
6,170,471(a)  
Neuberger Berman CLO XX, Ltd., Series 2015-20A, 
 
  
Class AR, 1.041% (3 Month USD LIBOR + 80 bps), 
 
  
1/15/28 (144A) 
6,170,743 
2,406,250(a)  
Neuberger Berman CLO XXII, Ltd., Series 2016-22A, 
 
  
Class XR, 1.123% (3 Month USD LIBOR + 90 bps), 
 
  
10/17/30 (144A) 
2,406,245 
546,794(a)  
Newtek Small Business Loan Trust, Series 2016-1A, 
 
  
Class A, 3.109% (1 Month USD LIBOR + 300 bps), 
 
  
2/25/42 (144A) 
547,995 
3,218,114(a)  
Newtek Small Business Loan Trust, Series 2017-1, 
 
  
Class A, 2.109% (1 Month USD LIBOR + 200 bps), 
 
  
2/25/43 (144A) 
3,201,133 
4,151,879(a)  
Newtek Small Business Loan Trust, Series 2018-1, 
 
  
Class A, 2.7% (PRIME + -55 bps), 2/25/44 (144A) 
4,050,588 
3,193,753(a)  
Newtek Small Business Loan Trust, Series 2018-1, 
 
  
Class B, 4.0% (PRIME + 75 bps), 2/25/44 (144A) 
2,929,521 
9,617,705(a)  
Newtek Small Business Loan Trust, Series 2019-1, 
 
  
Class A, 2.35% (PRIME + -90 bps), 12/25/44 (144A) 
9,472,639 
2,051,777(a)  
Newtek Small Business Loan Trust, Series 2019-1, 
 
  
Class B, 3.5% (PRIME + 25 bps), 12/25/44 (144A) 
1,954,318 
5,154,078  
NMEF Funding LLC, Series 2019-A, Class A, 2.73%, 
 
  
8/17/26 (144A) 
5,184,557 
1,800,000  
NMEF Funding LLC, Series 2019-A, Class C, 3.3%, 
 
  
8/17/26 (144A) 
1,845,515 
149,619(a)  
NovaStar Mortgage Funding Trust, Series 2003-1, 
 
  
Class A2, 0.889% (1 Month USD LIBOR + 
 
  
78 bps), 5/25/33 
148,751 
8,420,410  
Oasis LLC, Series 2020-1A, Class A, 3.82%, 
 
  
1/15/32 (144A) 
8,465,966 
5,424,470  
Oasis LLC, Series 2020-2A, Class A, 4.262%, 
 
  
5/15/32 (144A) 
5,480,284 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 31
 

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
9,250,000  
Oasis Securitization Funding LLC, Series 2021-1A, 
 
  
Class A, 2.579%, 2/15/33 (144A) 
$ 9,248,302 
1,875,000(a)  
Octagon Investment Partners XXI Ltd., Series 
 
  
2014-1A, Class XR3, 0.844% (3 Month USD LIBOR + 
 
  
65 bps), 2/14/31 (144A) 
1,875,000 
2,031,250(a)  
Octagon Investment Partners XXII, Ltd., Series 
 
  
2014-1A, Class XRR, 0.872% (3 Month USD LIBOR + 
 
  
65 bps), 1/22/30 (144A) 
2,031,205 
7,282,218  
Octane Receivables Trust, Series 2020-1A, Class A, 
 
  
1.71%, 2/20/25 (144A) 
7,346,935 
964,286(a)  
OHA Credit Funding 3, Ltd., Series 2019-3A, Class X, 
 
  
0.874% (3 Month USD LIBOR + 65 bps), 
 
  
7/20/32 (144A) 
964,285 
2,500,000(a)  
OHA Credit Funding 5, Ltd., Series 2020-5A, Class X, 
 
  
0.773% (3 Month USD LIBOR + 55 bps), 
 
  
4/18/33 (144A) 
2,470,690 
585,183(a)  
OneMain Financial Issuance Trust, Series 2017-1A, 
 
  
Class A2, 0.906% (1 Month USD LIBOR + 80 bps), 
 
  
9/14/32 (144A) 
585,407 
1,308,011  
OneMain Financial Issuance Trust, Series 2019-1A, 
 
  
Class A, 3.48%, 2/14/31 (144A) 
1,319,519 
170,000  
OneMain Financial Issuance Trust, Series 2019-1A, 
 
  
Class B, 3.79%, 2/14/31 (144A) 
174,299 
3,000,000  
Oportun Funding IX LLC, Series 2018-B, Class B, 
 
  
4.5%, 7/8/24 (144A) 
3,001,297 
6,000,000  
Oportun Funding XIV LLC, Series 2021-A, Class B, 
 
  
1.76%, 3/8/28 (144A) 
5,996,475 
3,000,000  
Oportun Funding XIV LLC, Series 2021-A, Class D, 
 
  
5.4%, 3/8/28 (144A) 
2,998,260 
4,033,573(a)  
Option One Mortgage Loan Trust, Series 2005-3, 
 
  
Class M2, 0.844% (1 Month USD LIBOR + 
 
  
74 bps), 8/25/35 
4,027,717 
446,349(a)  
Option One Mortgage Loan Trust Asset-Backed 
 

  Certificates, Series 2005-4, Class M1, 0.769%
  
(1 Month USD LIBOR + 66 bps), 11/25/35 
446,249 
12,950,000(a)  
Orec, Ltd., Series 2018-CRE1, Class A, 1.286% 
 
  
(1 Month USD LIBOR + 118 bps), 6/15/36 (144A) 
12,964,457 
11,000,000(a)  
Owl Rock CLO II Ltd., Series 2019-2A, Class ALR, 
 
  
0.0% (3 Month USD LIBOR + 155 bps), 4/20/33 (144A) 
11,001,144 
13,500,000(a)  
Owl Rock CLO II, Ltd., Series 2019-2A, Class A1L, 
 
  
1.974% (3 Month USD LIBOR + 175 bps), 
 
  
1/20/31 (144A) 
13,500,000 
2,000,000(a)  
Owl Rock CLO IV, Ltd., Series 2020-4A, Class A1, 
 
  
2.802% (3 Month USD LIBOR + 262 bps), 
 
  
5/20/29 (144A) 
2,003,786 
1,809,016  
Pagaya AI Debt Selection Trust, Series 2020-3, 
 
  
Class A, 2.1%, 5/17/27 (144A) 
1,821,514 
7,500,000  
Pagaya AI Debt Selection Trust, Series 2021-1, 
 
  
Class A, 1.18%, 11/15/27 (144A) 
7,499,982 
 
The accompanying notes are an integral part of these financial statements.
32 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
4,000,000(a)  
Palmer Square Loan Funding, Ltd., Series 2020-4A, 
 
  
Class C, 3.788% (3 Month USD LIBOR + 360 bps), 
 
  
11/25/28 (144A) 
$ 4,020,456 
1,250,000(a)  
Palmer Square Loan Funding, Ltd., Series 2021-2A, 
 

 Class D, 0.0% (3 Month USD LIBOR + 500 bps), 
  
5/20/29 (144A) 
1,250,000 
6,032,171  
Pawnee Equipment Receivables LLC, Series 2019-1, 
 
  
Class A2, 2.29%, 10/15/24 (144A) 
6,105,744 
3,171,936  
Pawnee Equipment Receivables LLC, Series 2020-1, 
 
  
Class A, 1.37%, 11/17/25 (144A) 
3,181,355 
6,940,130  
PEAR LLC, Series 2020-1, Class A, 3.75%, 
 
  
12/15/32 (144A) 
6,937,005 
30,000,000(a)  
PFS Financing Corp., Series 2019-B, Class A, 0.656% 
 
  
(1 Month USD LIBOR + 55 bps), 9/15/23 (144A) 
30,047,721 
2,500,000  
PFS Financing Corp., Series 2021-A, Class A, 0.71%, 
 
  
4/15/26 (144A) 
2,487,133 
16,117,000(a)  
Pnmac GMSR Issuer Trust, Series 2018-GT2, Class A, 
 
  
2.759% (1 Month USD LIBOR + 265 bps), 
 
  
8/25/25 (144A) 
16,036,861 
1,115,326  
Prosper Marketplace Issuance Trust, Series 2019-4A, 
 
  
Class A, 2.48%, 2/17/26 (144A) 
1,119,339 
5,190,949(a)  
RAAC Trust, Series 2006-RP1, Class M2, 1.309% 
 
  
(1 Month USD LIBOR + 120 bps), 10/25/45 (144A) 
5,233,574 
405,101(a)  
RAMP Trust, Series 2005-EFC6, Class M2, 0.754% 
 
  
(1 Month USD LIBOR + 43 bps), 11/25/35 
404,615 
2,091,978(a)  
RAMP Trust, Series 2006-RZ4, Class A3, 0.379% 
 
  
(1 Month USD LIBOR + 27 bps), 10/25/36 
2,079,069 
2,197(a)  
RASC Trust, Series 2005-EMX4, Class M2, 0.769% 
 
  
(1 Month USD LIBOR + 44 bps), 11/25/35 
2,197 
654,239(a)  
RASC Trust, Series 2005-KS1, Class M1, 0.784% 
 
  
(1 Month USD LIBOR + 45 bps), 2/25/35 
654,583 
3,692,329(a)  
RASC Trust, Series 2005-KS7, Class M5, 1.024% 
 
  
(1 Month USD LIBOR + 61 bps), 8/25/35 
3,690,106 
9,029,425(a)  
ReadyCap Lending Small Business Loan Trust, 
 
  
Series 2019-2, Class A, 2.75% (PRIME + -50 bps), 
 
  
12/27/44 (144A) 
8,614,024 
191,559(a)  
Regatta VI Funding Ltd., Series 2016-1A, Class AR, 
 
  
1.304% (3 Month USD LIBOR + 108 bps), 
 
  
7/20/28 (144A) 
191,581 
6,400,000  
Republic FInance Issuance Trust, Series 2019-A, 
 
  
Class A, 3.43%, 11/22/27 (144A) 
6,491,199 
7,500,000+(a)  
Rosy, Series 2018-1, Class A2, 3.377% (1 Month USD 
 
  
LIBOR + 325 bps), 12/15/25 (144A) 
7,200,000 
25,022(a)  
Salomon Mortgage Loan Trust, Series 2001-CB4, 
 
  
Class 1A1, 1.009% (1 Month USD LIBOR + 
 
  
90 bps), 11/25/33 
25,023 
3,037,432(a)  
Santander Drive Auto Receivables Trust, Series 
 
  
2020-1, Class A2B, 1.656% (1 Month USD LIBOR + 
 
  
155 bps), 1/17/23 
3,042,572 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 33
 

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
450,416(a)  
Saxon Asset Securities Trust, Series 2006-2, 
 

 Class A3C, 0.259% (1 Month USD LIBOR + 
  
15 bps), 9/25/36 
$ 450,189 
6,011,283  
SCF Equipment Leasing LLC, Series 2019-2A, 
 
  
Class A1, 2.22%, 6/20/24 (144A) 
6,053,858 
1,500,000  
SCF Equipment Leasing LLC, Series 2021-1A, 
 
  
Class A3, 0.83%, 8/21/28 (144A) 
1,488,756 
11,104(a)  
Securitized Asset Backed Receivables LLC Trust, 
 
  
Series 2005-OP2, Class M1, 0.754% (1 Month USD 
 
  
LIBOR + 65 bps), 10/25/35 
11,091 
326,363(a)  
Security National Mortgage Loan Trust, Series 
 
  
2007-1A, Class 2A, 0.459% (1 Month USD LIBOR + 
 
  
35 bps), 4/25/37 (144A) 
326,056 
1,208,054(a)  
SG Mortgage Securities Trust, Series 2005-OPT1, 
 
  
Class M1, 0.754% (1 Month USD LIBOR + 
 
  
65 bps), 10/25/35 
1,208,846 
1,500,000  
Sierra Timeshare Receivables Funding LLC, Series 
 
  
2021-1A, Class A, 0.99%, 11/20/37 (144A) 
1,496,175 
1,650,000  
Sierra Timeshare Receivables Funding LLC, Series 
 
  
2021-1A, Class D, 3.17%, 11/20/37 (144A) 
1,648,766 
2,000,000(a)  
Signal Peak CLO 1, Ltd., Series 2014-1A, Class BRR, 
 

 1.973% (3 Month USD LIBOR + 175 bps), 
  
1/17/29 (144A) 
2,000,298 
6,806,692(a)  
SLM Private Credit Student Loan Trust, Series 2007-A, 
 

 Class A4A, 0.424% (3 Month USD LIBOR + 
  
24 bps), 12/16/41 
6,627,720 
13,166,193(a)  
SLM Student Loan Trust, Series 2006-10, Class A6, 
 
  
0.368% (3 Month USD LIBOR + 15 bps), 3/25/44 
12,820,145 
1,913,222  
Small Business Lending Trust, Series 2019-A, Class A, 
 
  
2.85%, 7/15/26 (144A) 
1,910,441 
3,898,176  
Small Business Lending Trust, Series 2020-A, Class A, 
 
  
2.62%, 12/15/26 (144A) 
3,912,893 
1,500,000  
Small Business Lending Trust, Series 2020-A, Class B, 
 
  
3.2%, 12/15/26 (144A) 
1,508,218 
1,000,000  
Small Business Lending Trust, Series 2020-A, Class C, 
 
  
5.01%, 12/15/26 (144A) 
928,949 
3,516,258  
Sofi Consumer Loan Program LLC, Series 2016-1, 
 
  
Class A, 3.26%, 8/25/25 (144A) 
3,522,859 
4,008,386  
Sofi Consumer Loan Program Trust, Series 2018-1, 
 
  
Class B, 3.65%, 2/25/27 (144A) 
4,076,661 
627,399  
Sofi Consumer Loan Program Trust, Series 2019-1, 
 
  
Class A, 3.24%, 2/25/28 (144A) 
629,998 
580,758  
Sofi Consumer Loan Program Trust, Series 2019-2, 
 
  
Class A, 3.01%, 4/25/28 (144A) 
584,963 
548,783(a)  
Sofi Professional Loan Program LLC, Series 2015-C, 
 
  
Class A1, 1.159% (1 Month USD LIBOR + 
 
  
105 bps), 8/27/35 (144A) 
549,182 
1,011,361(a)  
Sofi Professional Loan Program LLC, Series 2015-D, 
 
  
Class A1, 1.609% (1 Month USD LIBOR + 150 bps), 
 
  
10/27/36 (144A) 
1,021,458 

 The accompanying notes are an integral part of these financial statements.
34 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,022,537(a)  
Sofi Professional Loan Program LLC, Series 2016-A, 
 
 
 
Class A1, 1.859% (1 Month USD LIBOR + 
 
 
 
175 bps), 8/25/36 (144A) 
$ 1,033,748 
663,141(a)  
Sofi Professional Loan Program LLC, Series 2016-B, 
 
 
 
Class A1, 1.309% (1 Month USD LIBOR + 
 
 
 
120 bps), 6/25/33 (144A) 
667,170 
1,756,022(a)  
Sofi Professional Loan Program LLC, Series 2016-C, 
 
 
 
Class A1, 1.209% (1 Month USD LIBOR + 
 
 
 
110 bps), 10/27/36 (144A) 
1,764,545 
429,537(a)  
Sofi Professional Loan Program LLC, Series 2016-D, 
 
 
 
Class A1, 1.059% (1 Month USD LIBOR + 
 
 
 
95 bps), 1/25/39 (144A) 
431,322 
913,885(a)  
Sofi Professional Loan Program LLC, Series 2016-E, 
 
 
 
Class A1, 0.959% (1 Month USD LIBOR + 
 
 
 
85 bps), 7/25/39 (144A) 
915,793 
294,936(a)  
Sofi Professional Loan Program LLC, Series 2017-A, 
 
 
 
Class A1, 0.809% (1 Month USD LIBOR + 
 
 
 
70 bps), 3/26/40 (144A) 
295,088 
345,855(a)  
Sofi Professional Loan Program LLC, Series 2017-C, 
 
 
 
Class A1, 0.709% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/25/40 (144A) 
345,381 
463,113(a)  
Sofi Professional Loan Program LLC, Series 2017-E, 
 
 
 
Class A1, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 11/26/40 (144A) 
463,113 
903,199(a)  
Sofi Professional Loan Program LLC, Series 2018-A, 
 
 
 
Class A1, 0.459% (1 Month USD LIBOR + 
 
 
 
35 bps), 2/25/42 (144A) 
898,303 
1,934,651  
Sofi Professional Loan Program LLC, Series 2019-C, 
 
 
 
Class A1FX, 2.13%, 11/16/48 (144A) 
1,942,255 
1,200,000(a)  
Sound Point CLO XXV, Ltd., Series 2019-4A, Class X, 
 
 
 
0.891% (3 Month USD LIBOR + 65 bps), 
 
 
 
1/15/33 (144A) 
1,199,999 
3,930,323  
SpringCastle America Funding LLC, Series 2020-AA, 
 
 
 
Class A, 1.97%, 9/25/37 (144A) 
3,960,904 
5,001,224  
Springleaf Funding Trust, Series 2015-BA, Class A, 
 
 
 
3.48%, 5/15/28 (144A) 
5,010,115 
2,726(a)  
Structured Asset Investment Loan Trust, Series 
 
 
 
2005-HE1, Class M1, 0.814% (1 Month USD LIBOR + 
 
 
 
71 bps), 7/25/35 
2,791 
2,376,949(a)  
Structured Asset Investment Loan Trust, Series 
 
 
 
2005-HE3, Class M1, 0.829% (1 Month USD LIBOR + 
 
 
 
72 bps), 9/25/35 
2,369,470 
50,641(a)  
Structured Asset Securities Corp. Mortgage Loan Trust, 
 

 Series 2005-NC2, Class M4, 0.814% (1 Month 
 
 
USD LIBOR + 71 bps), 5/25/35 
50,568 
3,391,567(a)  
Structured Asset Securities Corp. Mortgage Loan Trust, 
 

 Series 2006-OPT1, Class A1, 0.289% (1 Month 
 
 
USD LIBOR + 18 bps), 4/25/36 
3,254,290 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 35
 

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,024,835(a)  
Structured Asset Securities Corp. Mortgage Loan 
 
  
Trust, Series 2007-TC1, Class A, 0.409% (1 Month USD 
 
  
LIBOR + 30 bps), 4/25/31 (144A) 
$ 1,021,028 
6,000,000(a)  
STWD, Ltd., Series 2021-SIF1, Class A, 0.0% (3 Month 
 
  
USD LIBOR + 150 bps), 4/15/32 (144A) 
6,000,000 
1,500,000(a)  
STWD, Ltd., Series 2021-SIF1, Class C, 0.0% (3 Month 
 
  
USD LIBOR + 235 bps), 4/15/32 (144A) 
1,500,000 
482,903  
Tax Ease Funding LLC, Series 2016-1A, Class A, 
 
  
3.131%, 6/15/28 (144A) 
483,945 
3,149,273(a)  
Terwin Mortgage Trust, Series 2006-3, Class 1A2, 
 
  
0.569% (1 Month USD LIBOR + 46 bps), 
 
  
4/25/37 (144A) 
3,134,259 
125,000(a)  
THL Credit Wind River CLO, Ltd., Series 2015-1A, 
 
  
Class X, 0.874% (3 Month USD LIBOR + 
 
  
65 bps), 10/20/30 (144A) 
124,938 
1,586,000  
Tidewater Auto Receivables Trust, Series 2018-AA, 
 
  
Class E, 5.48%, 10/15/26 (144A) 
1,617,605 
7,228,065  
Tidewater Auto Receivables Trust, Series 2020-AA, 
 
  
Class A2, 1.39%, 8/15/24 (144A) 
7,271,379 
2,750,000  
Tidewater Auto Receivables Trust, Series 2020-AA, 
 
  
Class E, 3.35%, 7/17/28 (144A) 
2,793,586 
191,406  
TLF National Tax Lien Trust, Series 2017-1A, Class A, 
 
  
3.09%, 12/15/29 (144A) 
192,618 
9,426,887(a)  
Towd Point Asset Trust, Series 2018-SL1, Class A, 
 
  
0.709% (1 Month USD LIBOR + 60 bps), 
 
  
1/25/46 (144A) 
9,367,255 
11,000,000(a)  
Towd Point Asset Trust, Series 2018-SL1, Class B, 
 
  
1.159% (1 Month USD LIBOR + 105 bps), 
 
  
1/25/46 (144A) 
10,806,176 
63,465(b)  
Towd Point Mortgage Trust, Series 2015-4, Class A1, 
 
  
3.5%, 4/25/55 (144A) 
63,485 
664,238(b)  
Towd Point Mortgage Trust, Series 2015-5, Class A1B, 
 
  
2.75%, 5/25/55 (144A) 
665,842 
4,956,844(b)  
Towd Point Mortgage Trust, Series 2018-SJ1, 
 
  
Class XA, 5.0%, 10/25/58 (144A) 
5,076,473 
280,583(b)  
Towd Point Mortgage Trust, Series 2019-HY1, 
 
  
Class XA, 5.0%, 10/25/48 (144A) 
279,879 
4,467,729(a)  
Towd Point Mortgage Trust, Series 2019-HY2, 
 
  
Class A1, 1.109% (1 Month USD LIBOR + 100 bps), 
 
  
5/25/58 (144A) 
4,505,688 
1,015,315(b)  
Towd Point Mortgage Trust, Series 2019-HY2, 
 
  
Class XA, 5.0%, 5/25/58 (144A) 
1,014,626 
2,602,421(a)  
Towd Point Mortgage Trust, Series 2019-HY3, 
 
  
Class A1A, 1.109% (1 Month USD LIBOR + 100 bps), 
 
  
10/25/59 (144A) 
2,624,686 
4,132,076  
Towd Point Mortgage Trust, Series 2019-HY3, 
 
  
Class XA, 4.5%, 10/25/59 (144A) 
4,099,813 
1,980,643(b)  
Towd Point Mortgage Trust, Series 2019-SJ1, 
 
 
 
Class XA, 5.0%, 11/25/58 (144A) 
1,971,818 
 
The accompanying notes are an integral part of these financial statements.
36 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,872,173(b)  
Towd Point Mortgage Trust, Series 2019-SJ2, 
 
  
Class XA, 5.0%, 11/25/58 (144A) 
$ 1,947,521 
9,116,638(b)  
Towd Point Mortgage Trust, Series 2019-SJ3, 
 
  
Class A1, 3.0%, 11/25/59 (144A) 
9,216,906 
9,508,068(b)  
Towd Point Mortgage Trust, Series 2019-SJ3, 
 
  
Class XA, 4.5%, 11/25/59 (144A) 
9,484,298 
13,590,304  
Towd Point Mortgage Trust, Series 2020-4, 
 
  
Class XA, 3.25%, 10/25/60 (144A) 
13,529,730 
13,750,000(a)  
Trafigura Securitisation Finance Plc, Series 2018-1A, 
 
  
Class A1, 0.836% (1 Month USD LIBOR + 
 
  
73 bps), 3/15/22 (144A) 
13,746,342 
2,500,000  
Trafigura Securitisation Finance Plc, Series 2018-1A, 
 
  
Class B, 4.29%, 3/15/22 (144A) 
2,503,187 
1,346,154(a)  
Tralee CLO V, Ltd., Series 2018-5A, Class AX, 0.924% 
 
  
(3 Month USD LIBOR + 70 bps), 10/20/28 (144A) 
1,345,882 
16,400,000(a)  
TRTX Issuer, Ltd., Series 2019-FL3, Class C, 2.208% 
 
  
(1 Month USD LIBOR + 210 bps), 10/15/34 (144A) 
16,277,733 
3,999,370  
TVEST LLC, Series 2020-A, Class A, 4.5%, 
 
  
7/15/32 (144A) 
4,038,976 
1,966,448  
United Auto Credit Securitization Trust, Series 2020-1, 
 
  
Class A, 0.85%, 5/10/22 (144A) 
1,967,278 
4,700,000  
United Auto Credit Securitization Trust, Series 2021-1, 
 
  
Class F, 4.3%, 9/10/27 (144A) 
4,684,398 
3,297,663  
Upstart Securitization Trust, Series 2019-2, Class A, 
 
  
2.897%, 9/20/29 (144A) 
3,313,344 
6,671,532  
Upstart Securitization Trust, Series 2019-3, Class A, 
 
  
2.684%, 1/21/30 (144A) 
6,719,317 
13,516,957  
Upstart Securitization Trust, Series 2020-1, Class A, 
 
  
2.322%, 4/22/30 (144A) 
13,649,619 
6,828,630  
Upstart Securitization Trust, Series 2020-3, Class A, 
 
  
1.702%, 11/20/30 (144A) 
6,882,427 
2,250,000  
Upstart Securitization Trust, Series 2021-1, Class B, 
 
  
1.89%, 3/20/31 (144A) 
2,247,926 
7,710,762  
USASF Receivables LLC, Series 2020-1A, Class A, 
 
  
2.47%, 8/15/23 (144A) 
7,774,302 
131,579(a)  
Venture 32 CLO, Ltd., Series 2018-32RR, Class AX, 
 
  
0.973% (3 Month USD LIBOR + 75 bps), 
 
  
7/19/31 (144A) 
131,575 
964,113(a)  
Venture XXI CLO, Ltd., Series 2015-21A, Class AR, 
 
  
1.121% (3 Month USD LIBOR + 88 bps), 
 
  
7/15/27 (144A) 
964,156 
10,010,000(a)  
Verizon Owner Trust, Series 2019-A, Class A1B, 
 
  
0.441% (1 Month USD LIBOR + 33 bps), 9/20/23 
10,022,010 
9,178,804  
Veros Automobile Receivables Trust, Series 2020-1, 
 
  
Class A, 1.67%, 9/15/23 (144A) 
9,209,922 
2,000,000  
Veros Automobile Receivables Trust, Series 2020-1, 
 
  
Class B, 2.19%, 6/16/25 (144A) 
2,018,883 
2,616,577  
Volvo Financial Equipment LLC, Series 2019-2A, 
 
  
Class A2, 2.02%, 8/15/22 (144A) 
2,626,660 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 37
 

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
840,393  Westgate Resorts LLC, Series 2017-1A, Class B, 4.05%, 
 
 
 12/20/30 (144A) $ 836,469 
2,228,152  Westgate Resorts LLC, Series 2018-1A, Class B, 3.58%, 
 
 
 12/20/31 (144A) 2,222,152 
345,450  Westgate Resorts LLC, Series 2018-1A, Class C, 4.1%, 
 
 
 12/20/31 (144A) 343,012 
2,054,061  Westgate Resorts LLC, Series 2020-1A, Class A, 
 
 
 2.713%, 3/20/34 (144A) 2,098,172 
2,464,873  Westgate Resorts LLC, Series 2020-1A, Class C, 
 
 
 6.213%, 3/20/34 (144A) 2,598,573 
7,585(a)  Wilshire Mortgage Loan Trust, Series 1997-2, 
 
 
 Class A6, 0.389% (1 Month USD LIBOR + 
 
 
 28 bps), 5/25/28 7,581 
1,590,380(a)  Wind River CLO, Ltd., Series 2016-1A, Class AR, 
 
 
 1.291% (3 Month USD LIBOR + 105 bps), 
 
 
 7/15/28 (144A) 1,590,471 
5,000,000(a)  Woodmont Trust, Series 2020-7A, Class A1A, 
 
 
 2.047% (3 Month USD LIBOR + 190 bps), 
 
 
 
1/15/32 (144A) 
5,048,450 
 
 TOTAL ASSET BACKED SECURITIES 
 
 
 
(Cost $1,157,673,001) 
$1,159,808,012 
 
 COLLATERALIZED MORTGAGE OBLIGATIONS — 
 
 
 15.8% of Net Assets 
 
71,999(b)  Bear Stearns Mortgage Securities, Inc., Series 1997-6, 
 
 
 Class 3B1, 2.82%, 6/25/30 $ 73,936 
8,800,885(a)  Bellemeade Re, Ltd., Series 2017-1, Class M2, 
 
 
 3.459% (1 Month USD LIBOR + 335 bps), 
 
 
 10/25/27 (144A) 8,795,408 
6,533,876(a)  Bellemeade Re, Ltd., Series 2018-1A, Class M1B, 
 
 
 1.709% (1 Month USD LIBOR + 160 bps), 
 
 
 4/25/28 (144A) 6,535,917 
2,319,316(a)  Bellemeade Re, Ltd., Series 2018-3A, Class M1B, 
 
 
 1.959% (1 Month USD LIBOR + 185 bps), 
 
 
 10/25/28 (144A) 2,332,119 
6,125,000(a)  Bellemeade Re, Ltd., Series 2018-3A, Class M2, 
 
 
 2.859% (1 Month USD LIBOR + 275 bps), 
 
 
 10/25/28 (144A) 6,153,596 
8,448(a)  Bellemeade Re, Ltd., Series 2019-1A, Class M1A, 
 
 
 1.409% (1 Month USD LIBOR + 130 bps), 
 
 
 3/25/29 (144A) 8,449 
5,290,000(a)  Bellemeade Re, Ltd., Series 2019-1A, Class M1B, 
 
 
 1.859% (1 Month USD LIBOR + 175 bps), 
 
 
 3/25/29 (144A) 5,234,036 
2,800,000(a)  Bellemeade Re, Ltd., Series 2019-3A, Class B1, 
 
 
 2.609% (1 Month USD LIBOR + 250 bps), 
 
 
 7/25/29 (144A) 2,799,998 
10,671,000(a)  Bellemeade Re, Ltd., Series 2019-3A, Class M1B, 
 
 
 1.709% (1 Month USD LIBOR + 160 bps), 
 
 
 7/25/29 (144A) 10,719,631 
 
The accompanying notes are an integral part of these financial statements.
38 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
10,150,000(a)  
Bellemeade Re, Ltd., Series 2019-4A, Class M1B, 
 
 
 
2.109% (1 Month USD LIBOR + 200 bps), 
 
 
 
10/25/29 (144A) 
$ 10,163,582 
5,000,000(a)  
Bellemeade Re, Ltd., Series 2019-4A, Class M1C, 
 
 
 
2.609% (1 Month USD LIBOR + 250 bps), 
 
 
 
10/25/29 (144A) 
5,025,135 
3,250,000(a)  
Bellemeade Re, Ltd., Series 2020-2A, Class M1B, 
 
 
 
3.309% (1 Month USD LIBOR + 320 bps), 
 
 
 
8/26/30 (144A) 
3,275,234 
3,250,000(a)  
Bellemeade Re, Ltd., Series 2020-2A, Class M1C, 
 
 
 
4.109% (1 Month USD LIBOR + 400 bps), 
 
 
 
8/26/30 (144A) 
3,306,365 
4,567,000(a)  
Bellemeade Re, Ltd., Series 2020-3A, Class M1B, 
 
 
 
2.959% (1 Month USD LIBOR + 285 bps), 
 
 
 
10/25/30 (144A) 
4,605,535 
8,160,000(a)  
Bellemeade Re, Ltd., Series 2020-3A, Class M1C, 
 
 
 
3.809% (1 Month USD LIBOR + 370 bps), 
 
 
 
10/25/30 (144A) 
8,298,208 
4,120,000(a)  
Bellemeade Re, Ltd., Series 2020-4A, Class M2B, 
 
 
 
3.709% (1 Month USD LIBOR + 360 bps), 
 
 
 
6/25/30 (144A) 
4,104,929 
4,457,722(a)  
Brass NO 8 Plc, Series 8A, Class A1, 0.894% 
 
 
 
(3 Month USD LIBOR + 70 bps), 11/16/66 (144A) 
4,476,044 
7,500,000(b)  
CFMT LLC, Series 2020-HB4, Class M4, 4.948%, 
 
 
 
12/26/30 (144A) 
7,497,698 
3,300,000(b)  
CFMT LLC, Series 2021-HB5, Class M3, 2.91%, 
 
 
 
2/25/31 (144A) 
3,279,179 
4,962,193(a)  
Chase Mortgage Finance Corp., Series 2019-CL1, 
 
 
 
Class M1, 1.459% (1 Month USD LIBOR + 135 bps), 
 
 
 
4/25/47 (144A) 
4,999,701 
85,482(a)  
CHL Mortgage Pass-Through Trust, Series 2003-15, 
 
 
 
Class 1A1, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 6/25/18 
85,482 
583  
Citicorp Mortgage Securities REMIC Pass-Through 
 
 
 
Certificates Trust, Series 2005-4, Class 2A1, 5.0%, 
 
 
 
7/25/20 
594 
18,269,081(a)  
Connecticut Avenue Securities Trust, Series 
 
 
 
2019-HRP1, Class M2, 2.259% (1 Month USD LIBOR + 
 
 
 
215 bps), 11/25/39 (144A) 
17,990,306 
62,863(a)  
CSFB Mortgage-Backed Pass-Through Certificates, 
 
 
 
Series 2004-AR5, Class 11A2, 0.849% (1 Month USD 
 
 
 
LIBOR + 74 bps), 6/25/34 
62,905 
459,997(a)  
Deer Creek CLO, Ltd., Series 2017-1A, Class X, 1.224% 
 
 
 
(3 Month USD LIBOR + 100 bps), 10/20/30 (144A) 
459,991 
4,410,148(a)  
Eagle Re, Ltd., Series 2018-1, Class M1, 1.809% 
 
 
 
(1 Month USD LIBOR + 170 bps), 11/25/28 (144A) 
4,430,886 
6,292,367(a)  
Eagle Re, Ltd., Series 2019-1, Class M1B, 1.909% 
 
 
 
(1 Month USD LIBOR + 180 bps), 4/25/29 (144A) 
6,304,818 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 39
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
3,054,000(a)  
Eagle Re Ltd., Series 2020-2, Class M1B, 4.109% 
 
 
 
(1 Month USD LIBOR + 400 bps), 10/25/30 (144A) 
$ 3,101,575 
2,720,000(a)  
Eagle Re, Ltd., Series 2020-2, Class M1C, 4.609% 
 
 
 
(1 Month USD LIBOR + 450 bps), 10/25/30 (144A) 
2,781,261 
3,908,959(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2016-C02, Class 1M2, 6.109% (1 Month USD LIBOR + 
 
 
 
600 bps), 9/25/28 
4,117,618 
9,077,630(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2016-C03, Class 2M2, 6.009% (1 Month USD LIBOR + 
 
 
 
590 bps), 10/25/28 
9,600,153 
10,526,604(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2017-C05, Class 1M2B, 2.309% (1 Month USD LIBOR + 
 
 
 
220 bps), 1/25/30 
10,620,089 
884,286(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2017-C07, Class 1M2A, 2.509% (1 Month USD LIBOR + 
 
 
 
240 bps), 5/25/30 
885,644 
8,657,113(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2018-C04, Class 2M2, 2.659% (1 Month USD LIBOR + 
 
 
 
255 bps), 12/25/30 
8,673,555 
197,677(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 1695, Class EG, 1.162% (1 Month USD LIBOR + 
 
 
105 bps), 3/15/24 
198,925 
124,555(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2106, Class F, 0.556% (1 Month USD LIBOR + 
 
 
45 bps), 12/15/28 
125,019 
76,615(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2122, Class FD, 0.456% (1 Month USD LIBOR + 
 
 
35 bps), 2/15/29 
75,046 
24,722(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2156, Class FQ, 0.456% (1 Month USD LIBOR + 
 
 
35 bps), 5/15/29 
24,401 
148,116(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2186, Class FY, 0.706% (1 Month USD LIBOR + 
 
 
60 bps), 4/15/28 
148,995 
35,826(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2368, Class AF, 1.056% (1 Month USD LIBOR + 
 
 
95 bps), 10/15/31 
36,200 
37,574(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2377, Class FE, 0.706% (1 Month USD LIBOR + 
 
 
60 bps), 11/15/31 
37,918 
93,883(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2411, Class FR, 0.706% (1 Month USD LIBOR +
 
 
 
60 bps), 6/15/31 
94,710 
75,693(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2432, Class FH, 0.806% (1 Month USD LIBOR +
 
 
 
70 bps), 3/15/32 
75,390 
193,003(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2439, Class F, 1.106% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
197,435 
 
The accompanying notes are an integral part of these financial statements.
40 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
265,985(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2470, Class AF, 1.106% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
$ 272,046 
163,066(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2471, Class FD, 1.106% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
166,810 
46,839(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2498, Class FQ, 0.706% (1 Month USD LIBOR + 
 
 
60 bps), 9/15/32 
47,283 
70,534(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2543, Class EF, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 12/15/32 
70,626 
325,974(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2551, Class FD, 0.506% (1 Month USD LIBOR + 
 
 
40 bps), 1/15/33 
328,754 
184,510(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2567, Class FJ, 0.506% (1 Month USD LIBOR +
 
 
 
40 bps), 2/15/33 
185,087 
91,148(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2577, Class FA, 0.656% (1 Month USD LIBOR +
 
 
 
55 bps), 2/15/33 
91,903 
7,283(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2585, Class FD, 0.606% (1 Month USD LIBOR +
 
 
 
50 bps), 12/15/32 
7,330 
99,573(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2614, Class FV, 1.615% (1 Month USD LIBOR +
 
 
 
150 bps), 5/15/33 
102,930 
153,658(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2631, Class FC, 0.506% (1 Month USD LIBOR +
 
 
 
40 bps), 6/15/33 
154,995 
88,643(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2711, Class FA, 1.106% (1 Month USD LIBOR +
 
 
 
100 bps), 11/15/33 
90,459 
142,612(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2916, Class NF, 0.356% (1 Month USD LIBOR +
 
 
 
25 bps), 1/15/35 
142,928 
314,107(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 2976, Class LF, 0.446% (1 Month USD LIBOR +
 
 
 
34 bps), 5/15/35 
315,989 
133,454(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3012, Class FE, 0.356% (1 Month USD LIBOR +
 
 
 
25 bps), 8/15/35 
133,662 
94,728(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3042, Class PF, 0.356% (1 Month USD LIBOR +
 
 
 
25 bps), 8/15/35 
94,969 
59,714(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3067, Class FA, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 11/15/35 
60,103 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 41

 Schedule of Investments | 3/31/21 (continued)
     
Principal  
 
 
 
Amount  
 
 
 
USD ($)  
 

 Value
 
 COLLATERALIZED MORTGAGE 
 
 
 
 OBLIGATIONS — (continued) 
 
 
59,487(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3102, Class FG, 0.406% (1 Month USD LIBOR +
  
 
 
30 bps), 1/15/36 
$ 59,704 
119,473(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3117, Class EF, 0.456% (1 Month USD LIBOR +
  
 
 
35 bps), 2/15/36 
 
120,140 
263,208(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3117, Class FE, 0.406% (1 Month USD LIBOR +
  
 
 
30 bps), 2/15/36 
 
264,187 
167,205(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3122, Class FP, 0.406% (1 Month USD LIBOR +
  
 
 
30 bps), 3/15/36 
 
167,895 
101,808(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3147, Class PF, 0.406% (1 Month USD LIBOR +
  
 
 
30 bps), 4/15/36 
 
102,228 
244,132(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3173, Class FC, 0.526% (1 Month USD LIBOR +
  
 
 
42 bps), 6/15/36 
 
245,996 
488,512(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3175, Class FE, 0.416% (1 Month USD LIBOR +
  
 
 
31 bps), 6/15/36 
 
489,263 
288,581(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3181, Class HF, 0.606% (1 Month USD LIBOR +
  
 
 
50 bps), 7/15/36 
 
292,597 
13,561(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3191, Class FE, 0.506% (1 Month USD LIBOR +
  
 
 
40 bps), 7/15/36 
 
13,678 
215,173(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3221, Class FW, 0.526% (1 Month USD LIBOR +
  
 
 
42 bps), 9/15/36 
 
218,244 
67,937(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3222, Class FN, 0.506% (1 Month USD LIBOR +
  
 
 
40 bps), 9/15/36 
 
68,439 
225,945(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3239, Class EF, 0.456% (1 Month USD LIBOR +
  
 
 
35 bps), 11/15/36 
 
227,542 
116,408(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3239, Class FB, 0.456% (1 Month USD LIBOR +
  
 
 
35 bps), 11/15/36 
 
117,227 
187,976(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3247, Class FA, 0.356% (1 Month USD LIBOR +
  
 
 
25 bps), 8/15/36 
 
188,574 
402,803(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3266, Class F, 0.406% (1 Month USD LIBOR +
  
 
 
30 bps), 1/15/37 
 
404,246 
163,932(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
 

 3307, Class FT, 0.346% (1 Month USD LIBOR +
  
 
 
24 bps), 7/15/34 
 
164,214 
 
The accompanying notes are an integral part of these financial statements.
42 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
 Value
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
20,859(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3315, Class F, 0.446% (1 Month USD LIBOR +
 
 
 
34 bps), 5/15/37 
$ 20,997 
397,472(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3373, Class FB, 0.686% (1 Month USD LIBOR +
 
 
 
58 bps), 10/15/37 
403,994 
54,397(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3376, Class FM, 0.726% (1 Month USD LIBOR +
 
 
 
62 bps), 10/15/37 
55,377 
22,128(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3560, Class FA, 1.356% (1 Month USD LIBOR +
 
 
 
125 bps), 5/15/37 
22,948 
242,553(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3610, Class FA, 0.806% (1 Month USD LIBOR +
 
 
 
70 bps), 12/15/39 
246,639 
113,729(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3708, Class PF, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 7/15/40 
114,196 
13,732(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3767, Class JF, 0.406% (1 Month USD LIBOR +
 
 
 
30 bps), 2/15/39 
13,739 
51,126(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3784, Class F, 0.506% (1 Month USD LIBOR +
 
 
 
40 bps), 7/15/23 
51,027 
14,003(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3792, Class DF, 0.506% (1 Month USD LIBOR +
 
 
 
40 bps), 11/15/40 
13,937 
25,813(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3867, Class FD, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 5/15/41 
25,962 
64,061(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3914, Class LF, 0.306% (1 Month USD LIBOR +
 
 
 
20 bps), 8/15/26 
63,837 
141,441(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3970, Class GF, 0.406% (1 Month USD LIBOR +
 
 
 
30 bps), 9/15/26 
141,401 
225,752(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 3982, Class FL, 0.656% (1 Month USD LIBOR +
 
 
 
55 bps), 12/15/39 
226,964 
112,790(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 4056, Class QF, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 12/15/41 
113,262 
118,361(a)  
Federal Home Loan Mortgage Corp. Strips, Series 237, 
 
 
 
Class F14, 0.506% (1 Month USD LIBOR + 
 
 
 
40 bps), 5/15/36 
118,174 
103,970(a)  
Federal Home Loan Mortgage Corp. Strips, Series 239, 
 
 
 
Class F29, 0.356% (1 Month USD LIBOR + 
 
 
 
25 bps), 8/15/36 
103,787 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 43

 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
449,467(a)  
Federal Home Loan Mortgage Corp. Strips, Series 
 

 239, Class F30, 0.406% (1 Month USD LIBOR +
 
 
 
30 bps), 8/15/36 
$ 446,702 
132,740(a)  
Federal Home Loan Mortgage Corp. Strips, Series 
 

 244, Class F22, 0.456% (1 Month USD LIBOR +
 
 
 
35 bps), 12/15/36 
132,912 
2,019(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 1991-124, Class FA, 1.009% (1 Month USD 
 
 
 
LIBOR + 90 bps), 9/25/21 
2,018 
16,081(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 1993-230, Class FA, 0.718% (1 Month USD 
 
 
 
LIBOR + 60 bps), 12/25/23 
16,024 
41,717(a)  
Federal National Mortgage Association REMICS, 
 

 Series 1993-247, Class FA, 1.857% (11th District
 
 
 
Cost of Funds Index + 140 bps), 12/25/23 
42,046 
41,717(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 1993-247, Class FE, 1.109% (1 Month USD 
 
 
 
LIBOR + 100 bps), 12/25/23 
41,814 
85,800(a)  
Federal National Mortgage Association REMICS, 
 

 Series 1994-40, Class FC, 0.609% (1 Month USD
 
 
 
LIBOR + 50 bps), 3/25/24 
86,594 
13,972(a)  
Federal National Mortgage Association REMICS, 
 

 Series 1997-46, Class FA, 0.608% (1 Month USD
 
 
 
LIBOR + 50 bps), 7/18/27 
13,874 
33,889(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 1998-21, Class F, 0.45% (1 Year CMT Index + 
 
 
 
35 bps), 3/25/28 
33,732 
80(a)  
Federal National Mortgage Association REMICS, 
 

 Series 1999-49, Class FB, 0.609% (1 Month USD
 
 
 
LIBOR + 50 bps), 3/25/23 
80 
32,975(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2000-47, Class FD, 0.659% (1 Month USD
 
 
 
LIBOR + 55 bps), 12/25/30 
33,215 
127,719(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 2001-35, Class F, 0.709% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/25/31 
128,875 
53,258(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 2001-37, Class F, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 8/25/31 
53,538 
263,932(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2001-50, Class FQ, 0.709% (1 Month USD
 
 
 
LIBOR + 60 bps), 11/25/31 
266,320 
116,130(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 2001-65, Class F, 0.709% (1 Month USD LIBOR + 
 
 
 
60 bps), 11/25/31 
117,181 
77,929(a)  
Federal National Mortgage Association REMICS, Series 
 

 2001-69, Class FA, 0.709% (1 Month USD LIBOR
 
 
 
+ 60 bps), 7/25/31 
78,641 
 
The accompanying notes are an integral part of these financial statements.
44 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
224,548(a)  
Federal National Mortgage Association REMICS, Series 
 

 2001-72, Class FB, 1.009% (1 Month USD LIBOR
 
 
 
+ 90 bps), 12/25/31 
$ 225,243 
61,143(a)  
Federal National Mortgage Association REMICS, Series 
 

 2001-81, Class FL, 0.758% (1 Month USD LIBOR
 
 
 
+ 65 bps), 1/18/32 
61,685 
101,503(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 2002-1, Class FC, 0.809% (1 Month USD LIBOR + 
 
 
 
70 bps), 1/25/32 
102,902 
310,169(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2002-13, Class FD, 1.009% (1 Month USD
 
 
 
LIBOR + 90 bps), 3/25/32 
315,021 
214,369(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2002-34, Class FA, 0.608% (1 Month USD
 
 
 
LIBOR + 50 bps), 5/18/32 
215,945 
164,329(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2002-56, Class FN, 1.109% (1 Month USD
 
 
 
LIBOR + 100 bps), 7/25/32 
168,205 
22,297(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2002-58, Class FD, 0.709% (1 Month USD
 
 
 
LIBOR + 60 bps), 8/25/32 
22,510 
99,928(a)  
Federal National Mortgage Association REMICS, Series 
 

 2002-77, Class F, 0.709% (1 Month USD LIBOR +
 
 
 
60 bps), 12/25/32 
100,073 
78,237(a)  
Federal National Mortgage Association REMICS, Series 
 

 2002-82, Class FB, 0.609% (1 Month USD LIBOR
 
 
 
+ 50 bps), 12/25/32 
78,740 
97,283(a)  
Federal National Mortgage Association REMICS, Series 
 

 2002-90, Class FH, 0.609% (1 Month USD LIBOR
 
 
 
+ 50 bps), 9/25/32 
97,900 
53,166(a)  
Federal National Mortgage Association REMICS, Series 
 

 2002-92, Class FB, 0.759% (1 Month USD LIBOR
 
 
 
+ 65 bps), 4/25/30 
53,715 
108,510(a)  
Federal National Mortgage Association REMICS, Series 
 

 2002-93, Class FH, 0.609% (1 Month USD LIBOR
 
 
 
+ 50 bps), 1/25/33 
107,248 
88,574(a)  
Federal National Mortgage Association REMICS, 
 
 
 
Series 2003-7, Class FA, 0.859% (1 Month USD LIBOR + 
 
 
 
75 bps), 2/25/33 
90,023 
180,552(a)  
Federal National Mortgage Association REMICS, Series 
 

 2003-8, Class FJ, 0.459% (1 Month USD LIBOR +
 
 
 
35 bps), 2/25/33 
180,732 
276,095(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-31, Class FM, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 4/25/33 
279,849 
119,657(a)  
Federal National Mortgage Association REMICS, 
 

 Series 2003-42, Class JF, 0.609% (1 Month USD
 
 
 
LIBOR + 50 bps), 5/25/33 
118,240 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 45

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
 
Amount  
 
 
 
USD ($)  
 

Value
 
 COLLATERALIZED MORTGAGE 
 
 
 
 OBLIGATIONS — (continued) 
 
 
54,986(a)  
Federal National Mortgage Association REMICS, 
 
 

 Series 2003-49, Class FY, 0.509% (1 Month USD
  
 
 
LIBOR + 40 bps), 6/25/23 
$ 54,975 
180,919(a)  
Federal National Mortgage Association REMICS, 
 
 
 
 
Series 2003-107, Class FD, 0.609% (1 Month USD 
 
 
 
 
LIBOR + 50 bps), 11/25/33 
 
178,694 
172,021(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2004-52, Class FW, 0.509% (1 Month USD LIBOR + 
 
 
 
 
40 bps), 7/25/34 
 
173,296 
47,725(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2004-54, Class FN, 0.559% (1 Month USD LIBOR + 
 
 
 
 
45 bps), 7/25/34 
 
47,162 
349,377(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2004-79, Class FM, 0.409% (1 Month USD LIBOR + 
 
 
 
 
30 bps), 11/25/24 
 
349,345 
17,972(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2004-91, Class HF, 0.409% (1 Month USD LIBOR + 
 
 
 
 
30 bps), 11/25/34 
 
17,991 
172,708(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2005-83, Class KT, 0.409% (1 Month USD LIBOR + 
 
 
 
 
30 bps), 10/25/35 
 
173,471 
221,861(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2005-83, Class LF, 0.419% (1 Month USD LIBOR + 
 
 
 
 
31 bps), 2/25/35 
 
222,526 
35,844(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-11, Class FB, 0.409% (1 Month USD LIBOR + 
 
 
 
 
30 bps), 3/25/36 
 
35,300 
113,274(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-33, Class FH, 0.459% (1 Month USD LIBOR + 
 
 
 
 
35 bps), 5/25/36 
 
113,894 
199,187(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-34, Class FA, 0.419% (1 Month USD LIBOR + 
 
 
 
 
31 bps), 5/25/36 
 
200,153 
201,057(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-42, Class CF, 0.559% (1 Month USD LIBOR + 
 
 
 
 
45 bps), 6/25/36 
 
203,280 
82,421(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-56, Class FC, 0.399% (1 Month USD LIBOR + 
 
 
 
 
29 bps), 7/25/36 
 
82,729 
30,369(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-70, Class BF, 0.659% (1 Month USD LIBOR + 
 
 
 
 
55 bps), 8/25/36 
 
30,812 
55,839(a)  
Federal National Mortgage Association REMICS, Series 
 
 

 2006-82, Class F, 0.679% (1 Month USD LIBOR +
  
 
 
57 bps), 9/25/36 
 
56,709 
100,314(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
 
2006-104, Class GF, 0.429% (1 Month USD LIBOR + 
 
 
 
 
32 bps), 11/25/36 
 
100,913 
 
The accompanying notes are an integral part of these financial statements.
46 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
 Value
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
42,892(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-115, Class BF, 0.349% (1 Month USD LIBOR + 
 
 
 
24 bps), 12/25/36 
$ 42,966 
133,847(a)  
Federal National Mortgage Association REMICS, Series 
 

 2007-2, Class FT, 0.359% (1 Month USD LIBOR +
 
 
 
25 bps), 2/25/37 
134,768 
150,436(a)  
Federal National Mortgage Association REMICS, Series 
 

 2007-7, Class FJ, 0.309% (1 Month USD LIBOR +
 
 
 
20 bps), 2/25/37 
150,553 
63,021(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-13, Class FA, 0.359% (1 Month USD LIBOR + 
 
 
 
25 bps), 3/25/37 
63,123 
147,738(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-41, Class FA, 0.509% (1 Month USD LIBOR + 
 
 
 
40 bps), 5/25/37 
148,863 
239,058(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-50, Class FN, 0.349% (1 Month USD LIBOR + 
 
 
 
24 bps), 6/25/37 
239,465 
22,788(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-57, Class FA, 0.339% (1 Month USD LIBOR + 
 
 
 
23 bps), 6/25/37 
22,836 
65,394(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-58, Class FA, 0.359% (1 Month USD LIBOR + 
 
 
 
25 bps), 6/25/37 
65,498 
62,686(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-66, Class FB, 0.509% (1 Month USD LIBOR + 
 
 
 
40 bps), 7/25/37 
62,997 
220,247(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-85, Class FG, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 9/25/37 
223,389 
277,270(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-91, Class FB, 0.709% (1 Month USD LIBOR + 
 
 
 
60 bps), 10/25/37 
282,033 
98,528(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-92, Class OF, 0.679% (1 Month USD LIBOR + 
 
 
 
57 bps), 9/25/37 
100,040 
55,597(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-93, Class FD, 0.659% (1 Month USD LIBOR + 
 
 
 
55 bps), 9/25/37 
56,397 
25,302(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-98, Class FD, 0.559% (1 Month USD LIBOR + 
 
 
 
45 bps), 6/25/37 
25,544 
34,699(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-100, Class YF, 0.659% (1 Month USD LIBOR + 
 
 
 
55 bps), 10/25/37 
35,371 
46,781(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-103, Class AF, 1.109% (1 Month USD LIBOR + 
 
 
 
100 bps), 3/25/37 
47,878 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 47
Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
48,747(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-110, Class FA, 0.729% (1 Month USD LIBOR + 
 
 
 
62 bps), 12/25/37 
$ 48,418 
35,831(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2008-6, Class FA, 0.809% (1 Month USD LIBOR + 
 
 
 
70 bps), 2/25/38 
36,486 
159,963(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2008-88, Class FA, 1.329% (1 Month USD LIBOR + 
 
 
 
122 bps), 10/25/38 
165,432 
62,612(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2009-113, Class FB, 0.659% (1 Month USD LIBOR + 
 
 
 
55 bps), 1/25/40 
63,459 
 
Federal National Mortgage Association REMICS, Series 
 
 
 
2010-17, Class DE, 3.5%, 6/25/21 
8(a)  
Federal National Mortgage Association REMICS, Series 
 

 2010-38, Class F, 0.409% (1 Month USD LIBOR + 
 
 
30 bps), 4/25/25 
53,410(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2010-43, Class FD, 0.709% (1 Month USD LIBOR + 
 
 
 
60 bps), 5/25/40 
54,295 
109,597(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2010-43, Class IF, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 5/25/40 
108,615 
91,259(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2011-19, Class FM, 0.659% (1 Month USD LIBOR + 
 
 
 
55 bps), 5/25/40 
91,533 
146,034(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2012-40, Class PF, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 4/25/42 
147,821 
1,366,930(a)  
Federal National Mortgage Association Trust, Series 
 
 
 
2003-W6, Class F, 0.468% (1 Month USD LIBOR + 
 
 
 
35 bps), 9/25/42 
1,374,695 
585,640(a)  
Federal National Mortgage Association Trust, Series 
 
 
 
2005-W3, Class 2AF, 0.329% (1 Month USD LIBOR + 
 
 
 
22 bps), 3/25/45 
583,489 
45,495(b)  
Federal National Mortgage Association Trust, Series 
 
 
 
2005-W3, Class 3A, 3.562%, 4/25/45 
49,523 
67,427(b)  
Federal National Mortgage Association Trust, Series 
 
 
 
2005-W4, Class 3A, 3.067%, 6/25/45 
71,572 
534,284(a)  
Federal National Mortgage Association Whole Loan, 
 
 
 
Series 2007-W1, Class 1AF1, 0.369% (1 Month USD 
 
 
 
LIBOR + 26 bps), 11/25/46 
530,611 
13,069,490(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2018-C01, Class 1EB1, 0.559% (1 Month USD LIBOR + 
 
 
 
45 bps), 7/25/30 
12,948,639 
1,440,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-DNA4, 
 
 
 
Class M2, 3.859% (1 Month USD LIBOR + 
 
 
 
375 bps), 8/25/50 (144A) 
1,452,856 
 
The accompanying notes are an integral part of these financial statements.
48 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
8,470,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA2, 
 
 
 
Class M2, 3.209% (1 Month USD LIBOR + 
 
 
 
310 bps), 3/25/50 (144A) 
$ 8,565,124 
9,394,228(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA3, 
 
 
 
Class M2, 3.709% (1 Month USD LIBOR + 
 
 
 
360 bps), 7/25/50 (144A) 
9,471,882 
7,550,000(a)  
Freddie Mac Stacr Remic Trust, Series 2021-HQA1, 
 
 
 
Class M2, 2.267% (SOFR30A + 
 
 
 
225 bps), 8/25/33 (144A) 
7,474,415 
14,263,814(a)  
Freddie Mac Stacr Trust, Series 2019-HRP1, Class M2, 
 
 
 
1.509% (1 Month USD LIBOR + 140 bps), 
 
 
 
2/25/49 (144A) 
14,165,111 
600,000(a)  
Freddie Mac Stacr Trust, Series 2019-HRP1, Class M3, 
 
 
 
2.359% (1 Month USD LIBOR + 225 bps), 
 
 
 
2/25/49 (144A) 
590,030 
10,745,450(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2015-DNA3, Class M3, 4.809% (1 Month 
 
 
 
USD LIBOR + 470 bps), 4/25/28 
11,134,568 
13,732,683(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA1, Class M3, 5.659% (1 Month 
 
 
 
USD LIBOR + 555 bps), 7/25/28 
14,424,356 
9,405,542(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA2, Class M3, 4.759% (1 Month 
 
 
 
USD LIBOR + 465 bps), 10/25/28 
9,841,795 
13,769,822(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA3, Class M3, 5.109% (1 Month 
 
 
 
USD LIBOR + 500 bps), 12/25/28 
14,484,617 
14,152,601(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA4, Class M3, 3.909% (1 Month 
 
 
 
USD LIBOR + 380 bps), 3/25/29 
14,705,405 
213,662(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-HQA3, Class M2, 1.459% (1 Month 
 
 
 
USD LIBOR + 135 bps), 3/25/29 
214,006 
4,221,656(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HQA1, Class M2, 3.659% (1 Month 
 
 
 
USD LIBOR + 355 bps), 8/25/29 
4,328,630 
6,459,999(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HRP1, Class M2, 2.559% (1 Month 
 
 
 
USD LIBOR + 245 bps), 12/25/42 
6,387,222 
998,445(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HRP1, Class M2D, 1.359% (1 Month 
 
 
 
USD LIBOR + 125 bps), 12/25/42 
943,351 
2,142,834(a)  
Gosforth Funding Plc, Series 2018-1A, Class A1, 0.638% 
 
(3 Month USD LIBOR + 45 bps), 8/25/60 (144A)
2,145,871 
81,142(a)
Government National Mortgage Association, Series
 

2003-7, Class FB, 0.306% (1 Month USD LIBOR +
20 bps), 1/16/33
80,987 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 49
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
377,555(a)  
Government National Mortgage Association, Series 
 

 2005-3, Class FC, 0.356% (1 Month USD LIBOR + 
 
 
25 bps), 1/16/35 
$ 378,021 
347,395(a)  
Government National Mortgage Association, Series 
 
 
 
2005-16, Class FA, 0.361% (1 Month USD LIBOR + 
 
 
 
25 bps), 2/20/35 
347,853 
115,116(a)  
Government National Mortgage Association, Series 
 
 
 
2008-69, Class FA, 0.611% (1 Month USD LIBOR + 
 
 
 
50 bps), 8/20/38 
115,526 
116,194(a)  
Government National Mortgage Association, Series 
 
 
 
2009-66, Class UF, 1.106% (1 Month USD LIBOR + 
 
 
 
100 bps), 8/16/39 
118,847 
300,349(a)  
Government National Mortgage Association, Series 
 
 
 
2009-88, Class MF, 0.711% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/20/39 
300,965 
88,706(a)  
Government National Mortgage Association, Series 
 
 
 
2009-92, Class FJ, 0.786% (1 Month USD LIBOR + 
 
 
 
68 bps), 10/16/39 
89,913 
11,951,215(a)  
Home Partners of America Trust, Series 2017-1, 
 

 Class A, 0.925% (1 Month USD LIBOR + 82 bps), 
 
 
7/17/34 (144A) 
11,964,122 
7,200,000(a)  
Home Partners of America Trust, Series 2017-1, 
 
 
 
Class B, 1.458% (1 Month USD LIBOR + 135 bps), 
 
 
 
7/17/34 (144A) 
7,199,997 
3,610,408(a)  
Home Re, Ltd., Series 2018-1, Class M1, 1.709% 
 
 
 
(1 Month USD LIBOR + 160 bps), 10/25/28 (144A) 
3,617,239 
4,464,414(a)  
Home Re, Ltd., Series 2019-1, Class M1, 1.759% 
 
 
 
(1 Month USD LIBOR + 165 bps), 5/25/29 (144A) 
4,465,839 
6,640,000(a)  
Home Re, Ltd., Series 2020-1, Class M1B, 3.359% 
 
 
 
(1 Month USD LIBOR + 325 bps), 10/25/30 (144A) 
6,764,816 
4,650,000(a)  
Home Re, Ltd., Series 2020-1, Class M1C, 4.259% 
 
 
 
(1 Month USD LIBOR + 415 bps), 10/25/30 (144A) 
4,773,998 
505,161(a)  
HomeBanc Mortgage Trust, Series 2005-3, Class A1, 
 
 
 
0.589% (1 Month USD LIBOR + 48 bps), 7/25/35 
506,772 
1,960,740(b)  
JP Morgan Mortgage Trust, Series 2014-IVR3, Class B4, 
 
 
 
2.553%, 9/25/44 (144A) 
1,969,641 
5,957,765(b)  
JP Morgan Mortgage Trust, Series 2014-IVR6, Class B1, 
 
 
 
2.486%, 7/25/44 (144A) 
6,042,836 
3,383,123(b)  
JP Morgan Mortgage Trust, Series 2017-4, Class A9, 
 
 
 
3.5%, 11/25/48 (144A) 
3,414,030 
19,775,267(a)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class A2, 0.859% (1 Month USD LIBOR + 75 bps), 
 
 
 
4/25/46 (144A) 
19,781,739 
3,240,851(a)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class A3, 0.859% (1 Month USD LIBOR + 75 bps), 
 
 
 
4/25/46 (144A) 
3,228,712 
8,213,454(b)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class B1, 2.178%, 4/25/46 (144A) 
8,263,772 
 
The accompanying notes are an integral part of these financial statements.
50 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
7,768,479(b)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class B2, 2.178%, 4/25/46 (144A) 
$ 7,758,981 
1,607,915(a)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class AM, 0.609% (1 Month USD LIBOR + 
 
 
 
50 bps), 5/25/33 (144A) 
1,582,381 
6,280,309(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B1, 0.836%, 5/25/33 (144A) 
6,080,722 
5,854,244(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B2, 0.836%, 5/25/33 (144A) 
5,600,548 
4,513,108(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B3, 0.836%, 5/25/33 (144A) 
4,251,334 
387,601(b)  
JP Morgan Trust, Series 2015-1, Class 1A14, 2.01% 
 
 
 
(1 Month USD LIBOR + 0 bps), 12/25/44 (144A) 
393,597 
21,342,725(a)  
LSTAR Securities Investment, Ltd., Series 2019-3, 
 
 
 
Class A1, 1.615% (1 Month USD LIBOR + 
 
 
 
150 bps), 4/1/24 (144A) 
21,307,744 
26,545,382(a)  
LSTAR Securities Investment, Ltd., Series 2019-4, 
 
 
 
Class A1, 1.615% (1 Month USD LIBOR + 
 
 
 
150 bps), 5/1/24 (144A) 
26,352,532 
14,930,235(a)  
LSTAR Securities Investment Ltd., Series 2021-1, 
 
 
 
Class A, 1.915% (1 Month USD LIBOR + 
 
 
 
180 bps), 2/1/26 (144A) 
14,970,487 
13,000,000(a)  
LSTAR Securities Investment Ltd., Series 2021-2, 
 
 
 
Class A1, 0.0% (1 Month USD LIBOR + 
 
 
 
170 bps), 3/2/26 (144A) 
13,000,000 
10,513(b)  
Merrill Lynch Mortgage Investors Trust, Series 2003-G, 
 
 
 
Class A3, 1.83%, 1/25/29 
10,662 
524,655(a)  
Merrill Lynch Mortgage Investors Trust, Series 2003-H, 
 
 
 
Class A1, 0.749% (1 Month USD LIBOR + 
 
 
 
64 bps), 1/25/29 
522,906 
283,484(a)  
Merrill Lynch Mortgage Investors Trust, Series 2004-B, 
 
 
 
Class A2, 0.794% (6 Month USD LIBOR + 
 
 
 
54 bps), 5/25/29 
283,250 
23,544(a)  
Merrill Lynch Mortgage Investors Trust, Series 2004-C, 
 
 
 
Class A2B, 1.264% (6 Month USD LIBOR + 
 
 
 
100 bps), 7/25/29 
23,439 
95,641(b)  
Merrill Lynch Mortgage Investors Trust, Series 2004-D, 
 
 
 
Class A3, 1.989%, 9/25/29 
95,952 
1,812,950(b)  
Morgan Stanley Residential Mortgage Loan Trust, 
 
 
 
Series 2014-1A, Class A1, 2.522%, 6/25/44 (144A) 
1,862,557 
2,564,000(b)  
Morgan Stanley Residential Mortgage Loan Trust, 
 
 
 
Series 2014-1A, Class B4, 2.522%, 6/25/44 (144A) 
2,733,288 
700,000(a)  
Mortgage Insurance-Linked Notes, Series 2019-1, 
 
 
 
Class M1, 2.009% (1 Month USD LIBOR + 
 
 
 
190 bps), 11/26/29 (144A) 
700,973 
5,356,955(a)  
Oaktown Re II, Ltd., Series 2018-1A, Class M1, 1.659% 
 
 
 
(1 Month USD LIBOR + 155 bps), 7/25/28 (144A) 
5,358,672 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 51

Schedule of Investments | 3/31/21 (continued)
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
3,620,000(a)  
Oaktown Re III, Ltd., Series 2019-1A, Class B1A, 3.609% 
 
 
 
(1 Month USD LIBOR + 350 bps), 7/25/29 (144A) 
$ 3,641,837 
13,573,000(a)  
Oaktown Re III, Ltd., Series 2019-1A, Class M1B, 2.059% 
 
 
 
(1 Month USD LIBOR + 195 bps), 7/25/29 (144A) 
13,647,328 
3,898,018(a)  
Oaktown Re IV, Ltd., Series 2020-1A, Class M1B, 4.859% 
 
 
 
(1 Month USD LIBOR + 475 bps), 7/25/30 (144A) 
3,928,850 
4,300,000(a)  
Oaktown Re V, Ltd., Series 2020-2A, Class M1B, 3.709% 
 
 
 
(1 Month USD LIBOR + 360 bps), 10/25/30 (144A) 
4,367,940 
2,599,617(a)  
OBX Trust, Series 2019-EXP1, Class 2A1A, 1.059% 
 
 
 
(1 Month USD LIBOR + 95 bps), 1/25/59 (144A) 
2,602,988 
1,271,190(a)  
Pepper Residential Securities Trust, Series 21A, 
 
 
 
Class A1U, 0.986% (1 Month USD LIBOR + 
 
 
 
88 bps), 1/16/60 (144A) 
1,272,822 
2,472,928(a)  
Pepper Residential Securities Trust No. 22, Series 22A, 
 
 
 
Class A1U, 1.111% (1 Month USD LIBOR + 
 
 
 
100 bps), 6/20/60 (144A) 
2,471,591 
6,083,288(a)  
Pepper Residential Securities Trust No. 25, Series 25A, 
 
 
 
Class A1U, 1.036% (1 Month USD LIBOR + 
 
 
 
93 bps), 3/12/61 (144A) 
6,097,955 
8,000,000(a)  
PMT Credit Risk Transfer Trust, Series 2021-1R, 
 
 
 
Class A, 3.015% (1 Month USD LIBOR + 290 bps), 
 
 
 
2/27/24 (144A) 
7,990,666 
6,900,000(a)  
Provident Funding Mortgage Warehouse Securitization 
 
 
 
Trust, Series 2021-1, Class G, 0.0% (1 Month USD 
 
 
 
LIBOR + 550 bps), 2/25/55 (144A) 
6,900,000 
741,471(a)  
Radnor Re, Ltd., Series 2018-1, Class M1, 1.509% 
 
 
 
(1 Month USD LIBOR + 140 bps), 3/25/28 (144A) 
741,578 
4,967,751(a)  
Radnor Re, Ltd., Series 2019-1, Class M1B, 2.059% 
 
 
 
(1 Month USD LIBOR + 195 bps), 2/25/29 (144A) 
4,981,165 
17,250,000(a)  
Radnor Re, Ltd., Series 2019-2, Class M1B, 1.859% 
 
 
 
(1 Month USD LIBOR + 175 bps), 6/25/29 (144A) 
17,239,586 
7,590,000(a)  
Radnor Re, Ltd., Series 2020-2, Class M1B, 4.109% 
 
 
 
(1 Month USD LIBOR + 400 bps), 10/25/30 (144A) 
7,663,687 
2,740,000(a)  
Radnor Re, Ltd., Series 2020-2, Class M1C, 4.709% 
 
 
 
(1 Month USD LIBOR + 460 bps), 10/25/30 (144A) 
2,791,886 
1,645,778(a)  
RESI Finance LP, Series 2003-CB1, Class B3, 1.556% 
 
 
 
(1 Month USD LIBOR + 145 bps), 6/10/35 (144A) 
1,452,556 
3,310,313(a)  
Resimac MBS Trust, Series 2018-2A, Class A1A, 0.956% 
 
 
 
(1 Month USD LIBOR + 85 bps), 4/10/50 (144A) 
3,311,915 
247,489(a)  
Resimac Premier, Series 2017-1A, Class A1A, 1.057% 
 
 
 
(1 Month USD LIBOR + 95 bps), 9/11/48 (144A) 
247,575 
1,316,101(a)  
Resimac Premier, Series 2018-1A, Class A1, 0.906% 
 
 
 
(1 Month USD LIBOR + 80 bps), 11/10/49 (144A) 
1,317,714 
6,966,020(a)  
Resimac Premier, Series 2019-2A, Class A1, 1.056% 
 
 
 
(1 Month USD LIBOR + 95 bps), 2/10/51 (144A) 
6,988,054 
3,562,160(a)  
Resimac Premier, Series 2020-1A, Class A1A, 1.153% 
 
 
 
(1 Month USD LIBOR + 105 bps), 2/7/52 (144A) 
3,584,139 
 
The accompanying notes are an integral part of these financial statements.
52 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
3,609,992(b)  RMF Buyout Issuance Trust, Series 2020-1, Class A, 
 
 
 2.158%, 2/25/30 (144A) $ 3,615,962 
2,000,000(b)  RMF Buyout Issuance Trust, Series 2020-1, Class M1, 
 
 
 2.332%, 2/25/30 (144A) 2,003,424 
3,866,078(b)  RMF Buyout Issuance Trust, Series 2020-2, Class A, 
 
 
 1.706%, 6/25/30 (144A) 3,875,093 
9,350,000(a)  STACR Trust, Series 2018-DNA3, Class M2B, 2.209% 
 
 
 (1 Month USD LIBOR + 210 bps), 9/25/48 (144A) 9,187,685 
7,247,796(a)  STACR Trust, Series 2018-HRP1, Class B1, 3.859% 
 
 
 (1 Month USD LIBOR + 375 bps), 4/25/43 (144A) 7,284,446 
5,312,005(a)  STACR Trust, Series 2018-HRP1, Class M2, 1.759% 
 
 
 (1 Month USD LIBOR + 165 bps), 4/25/43 (144A) 5,276,437 
8,450,000(a)  STACR Trust, Series 2018-HRP2, Class M3, 2.509% 
 
 
 (1 Month USD LIBOR + 240 bps), 2/25/47 (144A) 8,513,639 
7,283,477(a)  Towd Point HE Trust, Series 2019-HE1, Class A1, 
 
 
 1.009% (1 Month USD LIBOR + 90 bps), 4/25/48 (144A) 7,296,386 
4,993,973(a)  
Towd Point HE Trust, Series 2019-HE1, Class M1, 1.209% 
 
 
 (1 Month USD LIBOR + 110 bps), 4/25/48 (144A) 4,978,141 
5,280,000(a)  Traingle Re, Ltd., Series 2020-1, Class M1B, 4.009% 
 
 
 (1 Month USD LIBOR + 390 bps), 10/25/30 (144A) 5,364,996 
4,360,000(a)  Traingle Re, Ltd., Series 2020-1, Class M1C, 4.609% 
 
 
 (1 Month USD LIBOR + 450 bps), 10/25/30 (144A) 4,472,772 
6,440,000(a)  Traingle Re, Ltd., Series 2021-1, Class M1C, 3.507% 
 
 
 (1 Month USD LIBOR + 340 bps), 8/25/33 (144A) 6,439,990 
8,170,000(a)  Traingle Re, Ltd., Series 2021-1, Class M2, 4.007% 
 
 
 
(1 Month USD LIBOR + 390 bps), 8/25/33 (144A) 
8,169,984 
 
 TOTAL COLLATERALIZED MORTGAGE OBLIGATIONS 
 
 
 
(Cost $703,105,413) 
$ 699,054,752 

 COMMERCIAL MORTGAGE-BACKED 
 
 SECURITIES — 11.0% of Net Assets 
 
13,826,563(a)  ACRES Commercial Realty Corp., Series 2020-RSO8, 
 
 
 Class A, 1.258% (1 Month USD LIBOR + 
 
 
 115 bps), 3/15/35 (144A) $ 13,826,323 
1,190,558(a)  AREIT Trust, Series 2018-CRE2, Class A, 1.086% 
 
 
 (1 Month USD LIBOR + 98 bps), 11/14/35 (144A) 1,189,749 
12,500,000(a)  Austin Fairmont Hotel Trust, Series 2019-FAIR, 
 
 
 Class E, 2.356% (1 Month USD LIBOR + 225 bps), 
 
 
 9/15/32 (144A) 11,999,551 
8,000,000(a)  BAMLL Commercial Mortgage Securities Trust, 
 

 Series 2019-RLJ, Class C, 1.706% (1 Month USD 
 
 LIBOR + 160 bps), 4/15/36 (144A) 7,920,470 
1,150,000(a)  BFLD Trust, Series 2020-OBRK, Class A, 2.156% 
 
 
 (1 Month USD LIBOR + 205 bps), 11/15/28 (144A) 1,161,521 
9,450,000(a)  BHP Trust, Series 2019-BXHP, Class D, 1.877% 
 
 
 (1 Month USD LIBOR + 177 bps), 8/15/36 (144A) 9,444,302 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 53
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
7,750,000(a)  
BTH-13 Mortgage Backed Securities Trust, Series 
 

 2018-13, Class A, 2.62% (1 Month USD LIBOR + 
 
 
250 bps), 8/18/21 (144A) 
$ 7,737,229 
5,700,000(a)  
BTH-16 Mortgage-Backed Securities Trust, Series 
 
 
 
2018-16, Class A, 2.615% (1 Month USD LIBOR + 
 
 
 
250 bps), 8/4/21 (144A) 
5,728,705 
7,625,000(a)  
BTH-21 Mortgage-Backed Securities Trust, Series 
 
 
 
2018-21, Class A, 2.615% (1 Month USD LIBOR + 
 
 
 
250 bps), 10/7/21 (144A) 
7,615,354 
5,884,925(a)  
BTH-3 Mortgage-Backed Securities Trust, Series 
 

 2018-3, Class A, 2.615% (1 Month USD LIBOR +
 
 
 
250 bps), 7/8/21 
5,851,285 
5,810,000(a)  
BX Commercial Mortgage Trust, Series 2018-IND, 
 
 
 
Class D, 1.406% (1 Month USD LIBOR + 130 bps), 
 
 
 
11/15/35 (144A) 
5,809,998 
15,339,738(a)  
BX Commercial Mortgage Trust, Series 2019-XL, 
 
 
 
Class G, 2.406% (1 Month USD LIBOR + 230 bps), 
 
 
 
10/15/36 (144A) 
15,329,238 
9,300,000(a)  
BX Trust, Series 2019-ATL, Class B, 1.493% (1 Month 
 
 
 
USD LIBOR + 139 bps), 10/15/36 (144A) 
9,253,449 
8,000,000(a)  
BXP Trust, Series 2017-CQHP, Class B, 1.206% 
 
 
 
(1 Month USD LIBOR + 110 bps), 11/15/34 (144A) 
7,683,006 
2,171,167(a)  
CG-CCRE Commercial Mortgage Trust, Series 
 
 
 
2014-FL1, Class B, 1.256% (1 Month USD LIBOR + 
 
 
 
115 bps), 6/15/31 (144A) 
2,109,024 
721,188(a)  
CG-CCRE Commercial Mortgage Trust, Series 
 
 
 
2014-FL2, Class A, 1.96% (1 Month USD LIBOR + 
 
 
 
185 bps), 11/15/31 (144A) 
691,301 
10,000,000(a)  
CGDB Commercial Mortgage Trust, Series 2019-MOB, 
 
 
 
Class C, 1.556% (1 Month USD LIBOR + 
 
 
 
145 bps), 11/15/36 (144A) 
9,987,966 
5,700,000(a)  
CGMS Commercial Mortgage Trust, Series 2017-MDRC, 
 
 
 
Class C, 1.406% (1 Month USD LIBOR + 
 
 
 
130 bps), 7/15/30 (144A) 
5,550,824 
14,911,528(a)  
CHC Commercial Mortgage Trust, Series 2019-CHC, 
 
 
 
Class C, 1.856% (1 Month USD LIBOR + 175 bps), 
 
 
 
6/15/34 (144A) 
14,610,313 
9,500,000(a)  
CHT Mortgage Trust, Series 2017-CSMO, Class C, 
 
 
 
1.606% (1 Month USD LIBOR + 150 bps), 
 
 
 
11/15/36 (144A) 
9,505,859 
8,750,000(a)  
Citigroup Commercial Mortgage Trust, Series 
 
 
 
2019-SST2, Class B, 1.206% (1 Month USD LIBOR + 
 
 
 
110 bps), 12/15/36 (144A) 
8,752,747 
5,500,000(a)  
Citigroup Commercial Mortgage Trust, Series 
 
 
 
2019-SST2, Class C, 1.406% (1 Month USD LIBOR + 
 
 
 
130 bps), 12/15/36 (144A) 
5,501,721 
6,000,000(a)  
CLNY Trust, Series 2019-IKPR, Class B, 1.584% 
 
 
 
(1 Month USD LIBOR + 148 bps), 11/15/38 (144A) 
5,984,951 
 
The accompanying notes are an integral part of these financial statements.
54 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
2,000,000(a)  
CLNY Trust, Series 2019-IKPR, Class E, 2.827% 
 
 
 
(1 Month USD LIBOR + 272 bps), 11/15/38 (144A) 
$ 1,920,019 
6,750,000(a)  
Credit Suisse Commercial Mortgage Securities Corp., 
 
 
 
Series 2019-SKLZ, Class B, 2.006% (1 Month USD 
 
 
 
LIBOR + 190 bps), 1/15/34 (144A) 
6,669,921 
10,000,000(a)  
Credit Suisse Mortgage Capital Certificates, Series 
 
 
 
2019-ICE4, Class E, 2.256% (1 Month USD LIBOR + 
 
 
 
215 bps), 5/15/36 (144A) 
10,015,211 
1,591,263(a)  
Freddie Mac Multifamily Structured Credit Risk, Series 
 
 
 
2021-MN1, Class M1, 2.017% (SOFR30A + 
 
 
 
200 bps), 1/25/51 (144A) 
1,595,208 
1,715,812(a)  
FREMF Mortgage Trust, Series 2014-KF05, Class B, 
 
 
 
4.119% (1 Month USD LIBOR + 400 bps), 
 
 
 
9/25/22 (144A) 
1,719,476 
227,372(a)  
FREMF Mortgage Trust, Series 2014-KS02, Class B, 
 
 
 
5.119% (1 Month USD LIBOR + 500 bps), 
 
 
 
8/25/23 (144A) 
227,372 
2,416,121(a)  
GPMT, Ltd., Series 2018-FL1, Class A, 1.01% (1 Month 
 
 
 
USD LIBOR + 90 bps), 11/21/35 (144A) 
2,419,482 
3,250,000(a)  
GPMT, Ltd., Series 2018-FL1, Class AS, 1.31% (1 Month 
 
 
 
USD LIBOR + 120 bps), 11/21/35 (144A) 
3,243,472 
8,000,000(a)  
Great Wolf Trust, Series 2019-WOLF, Class D, 2.039% 
 
 
 
(1 Month USD LIBOR + 193 bps), 12/15/36 (144A) 
7,854,676 
3,500,000(a)  
GS Mortgage Securities Corp. Trust, Series 2017-STAY, 
 
 
 
Class B, 1.456% (1 Month USD LIBOR + 
 
 
 
135 bps), 7/15/32 (144A) 
3,500,113 
10,900,000(a)  
GS Mortgage Securities Corp. Trust, Series 2018-TWR, 
 
 
 
Class A, 1.006% (1 Month USD LIBOR + 
 
 
 
90 bps), 7/15/31 (144A) 
10,845,310 
11,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2019-70P, 
 
 
 
Class D, 1.856% (1 Month USD LIBOR + 
 
 
 
175 bps), 10/15/36 (144A) 
10,800,116 
7,400,000(a)  
GS Mortgage Securities Corp. Trust, Series 2019-SMP, 
 
 
 
Class D, 2.056% (1 Month USD LIBOR + 
 
 
 
195 bps), 8/15/32 (144A) 
7,218,082 
10,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2020-DUNE, 
 
 
 
Class A, 1.206% (1 Month USD LIBOR + 
 
 
 
110 bps), 12/15/36 (144A) 
9,996,128 
9,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2020-DUNE, 
 
 
 
Class E, 2.606% (1 Month USD LIBOR + 
 
 
 
250 bps), 12/15/36 (144A) 
8,394,941 
4,300,000(a)  
GS Mortgage Securities Trust, Series 2018-HART, 
 
 
 
Class A, 1.196% (1 Month USD LIBOR + 109 bps), 
 
 
 
10/15/31 (144A) 
4,296,106 
9,729,000(a)  
GS Mortgage Securities Trust, Series 2018-HART, 
 
 
 
Class B, 1.406% (1 Month USD LIBOR + 130 bps), 
 
 
 
10/15/31 (144A) 
9,674,249 
8,135,347(a)  
HPLY Trust, Series 2019-HIT, Class C, 1.706% (1 Month 
 
 
 
USD LIBOR + 160 bps), 11/15/36 (144A) 
8,115,004 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 55

 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
4,665,000(a)  
InTown Hotel Portfolio Trust, Series 2018-STAY, 
 

 Class A, 1.056% (1 Month USD LIBOR + 95 bps), 
 
 
1/15/33 (144A) 
$ 4,667,838 
4,230,000(a)  
InTown Hotel Portfolio Trust, Series 2018-STAY, 
 
 
 
Class B, 1.406% (1 Month USD LIBOR + 130 bps), 
 
 
 
1/15/33 (144A) 
4,225,029 
11,900,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2017-FL11, Class B, 1.206% (1 Month USD 
 
 
 
LIBOR + 110 bps), 10/15/32 (144A) 
11,780,608 
7,300,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2018-PHH, Class B, 2.66% (1 Month USD 
 
 
 
LIBOR + 116 bps), 6/15/35 (144A) 
7,153,685 
2,800,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2018-WPT, Class BFL, 1.353% (1 Month 
 
 
 
USD LIBOR + 125 bps), 7/5/33 (144A) 
2,803,050 
4,000,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2018-WPT, Class CFL, 1.753% (1 Month 
 
 
 
USD LIBOR + 165 bps), 7/5/33 (144A) 
4,006,124 
3,600,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2019-BKWD, Class C, 1.706% (1 Month 
 
 
 
USD LIBOR + 160 bps), 9/15/29 (144A) 
3,593,110 
1,650,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2019-BKWD, Class E, 2.706% (1 Month 
 
 
 
USD LIBOR + 260 bps), 9/15/29 (144A) 
1,633,393 
10,300,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2019-MFP, Class E, 2.266% (1 Month USD 
 
 
 
LIBOR + 216 bps), 7/15/36 (144A) 
10,174,016 
6,735,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
 
 
Trust, Series 2020-609M, Class A, 1.476% (1 Month USD 
 
 
 
LIBOR + 137 bps), 10/15/33 (144A) 
6,751,769 
194,615  
JPMBB Commercial Mortgage Securities Trust, Series 
 
 
 
2014-C19, Class A2, 3.046%, 4/15/47 
194,419 
8,050,000(a)  
MBRT, Series 2019-MBR, Class B, 1.256% (1 Month USD 
 
 
 
LIBOR + 115 bps), 11/15/36 (144A) 
8,040,012 
14,381,380(a)  
MF1, Ltd., Series 2019-FL2, Class A, 1.239% (1 Month 
 
 
 
USD LIBOR + 113 bps), 12/25/34 (144A) 
14,390,298 
1,734,287(b)  
Morgan Stanley Capital I Trust, Series 2007-T25, 
 
 
 
Class AJ, 5.574%, 11/12/49 
1,363,583 
8,500,000(a)  
Morgan Stanley Capital I Trust, Series 2017-ASHF, 
 
 
 
Class B, 1.356% (1 Month USD LIBOR + 
 
 
 
125 bps), 11/15/34 (144A) 
8,493,531 
8,250,000(a)  
Morgan Stanley Capital I Trust, Series 2017-CLS, 
 
 
 
Class C, 1.106% (1 Month USD LIBOR + 
 
 
 
100 bps), 11/15/34 (144A) 
8,252,598 
9,610,247(a)  
Morgan Stanley Capital I Trust, Series 2018-BOP, 
 
 
 
Class B, 1.356% (1 Month USD LIBOR + 
 
 
 
125 bps), 8/15/33 (144A) 
9,553,662 
 
The accompanying notes are an integral part of these financial statements.
56 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
5,220,000(a)  MTRO Commercial Mortgage Trust, Series 2019-TECH, 
 
 
 Class C, 1.406% (1 Month USD LIBOR + 
 
 
 130 bps), 12/15/33 (144A) $ 5,206,801 
3,662,523(a)  Natixis Commercial Mortgage Securities Trust, Series 
 

 2018-FL1, Class MCR1, 2.456% (1 Month USD 
 
 LIBOR + 235 bps), 6/15/35 (144A) 3,604,965 
11,500,000(a)  Natixis Commercial Mortgage Securities Trust, Series 
 
 
 2019-MILE, Class B, 1.906% (1 Month USD LIBOR 
 
 
 + 180 bps), 7/15/36 (144A) 11,518,495 
6,847,638(a)  SLIDE, Series 2018-FUN, Class B, 1.356% (1 Month USD 
 
 
 LIBOR + 125 bps), 6/15/31 (144A) 6,787,148 
1,110,239(b)  Sutherland Commercial Mortgage Loans, Series 
 
 
 2017-SBC6, Class A, 3.192%, 5/25/37 (144A) 1,104,206 
4,374,433(a)  Tharaldson Hotel Portfolio Trust, Series 2018-THL, 
 
 
 Class C, 1.604% (1 Month USD LIBOR + 
 
 
 150 bps), 11/11/34 (144A) 4,357,986 
10,150,000(a)  VMC Finance LLC, Series 2018-FL2, Class B, 1.458% 
 
 
 (1 Month USD LIBOR + 135 bps), 10/15/35 (144A) 10,106,105 
1,496,899(b)  WaMu Commercial Mortgage Securities Trust, Series 
 
 
 2006-SL1, Class C, 2.216%, 11/23/43 (144A) 1,495,017 
12,800,000(a)  Wells Fargo Commercial Mortgage Trust, Series 
 
 
 2017-SMP, Class C, 1.431% (1 Month USD LIBOR + 
 
 
 133 bps), 12/15/34 (144A) 12,635,958 
13,125,000(a)  XCAL Mortgage Trust, Series 2019-1, Class A, 4.4% 
 
 
 (1 Month USD LIBOR + 225 bps), 11/6/21 (144A) 13,198,747 
14,200,000(a)  XCALI Mortgage Trust, Series 2020-1, Class A, 4.05% 
 
 
 (1 Month USD LIBOR + 240 bps), 1/22/23 (144A) 14,245,326 
13,500,000(a)  XCALI Mortgage Trust, Series 2020-2, Class A, 4.05% 
 
 
 (1 Month USD LIBOR + 200 bps), 2/7/23 (144A) 13,539,949 
4,375,000(a)  XCALI Mortgage Trust, Series 2020-5, Class A, 4.25% 
 
 
 
(1 Month USD LIBOR + 325 bps), 10/15/23 (144A) 
4,393,360 
 
 TOTAL COMMERCIAL MORTGAGE-BACKED SECURITIES 
 
 
 
(Cost $494,544,269) 
$ 491,020,560 
 
 CORPORATE BONDS — 29.5% of Net Assets 
 
 
 Aerospace & Defense — 0.2% 
 
10,000,000  Boeing Co., 1.167%, 2/4/23 $ 10,050,675 
 
 Total Aerospace & Defense $ 10,050,675 
 
 Auto Manufacturers — 3.0% 
 
6,575,000(a)  American Honda Finance Corp., 0.503% (3 Month 
 
 
 USD LIBOR + 28 bps), 1/12/24 $ 6,573,428 
3,960,000(a)  American Honda Finance Corp., 0.565% (3 Month 
 
 
 USD LIBOR + 37 bps), 5/10/23 3,973,053 
9,190,000(a)  American Honda Finance Corp., 0.733% (3 Month 
 
 
 USD LIBOR + 54 bps), 6/27/22 9,240,242 
12,323,000(a)  BMW US Capital LLC, 0.54% (SOFRRATE + 53 bps), 
 
 
 4/1/24 (144A) 12,342,674 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 57
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Auto Manufacturers — (continued) 
 
2,015,000(a)  
Ford Motor Credit Co. LLC, 1.104% (3 Month USD 
 
 
 
LIBOR + 88 bps), 10/12/21 
$ 2,005,287 
11,520,000  
General Motors Financial Co., Inc., 4.375%, 9/25/21 
11,733,277 
11,000,000(a)  
Nissan Motor Acceptance Corp., 0.825% (3 Month USD 
 
 
 
LIBOR + 64 bps), 3/8/24 (144A) 
10,974,880 
6,889,000(a)  
PACCAR Financial Corp., 0.455% (3 Month USD 
 
 
 
LIBOR + 26 bps), 5/10/21 
6,891,150 
11,000,000(a)  
Toyota Motor Credit Corp., 0.367% (SOFRRATE + 
 
 
 
33 bps), 1/11/24 
11,030,683 
22,255,000(a)  
Toyota Motor Credit Corp., 0.505% (3 Month USD 
 
 
 
LIBOR + 28 bps), 4/13/21 
22,256,951 
14,245,000(a)  
Volkswagen Group of America Finance LLC, 1.051% 
 
 
 
(3 Month USD LIBOR + 86 bps), 9/24/21 (144A) 
14,297,265 
5,550,000(a)  
Volkswagen Group of America Finance LLC, 1.141% 
 
 
 
(3 Month USD LIBOR + 94 bps), 11/12/21 (144A) 
5,578,529 
11,255,000  
Volkswagen Group of America Finance LLC, 2.5%, 
 
 
 
9/24/21 (144A) 
11,377,831 
6,460,000  
Volkswagen Group of America Finance LLC, 2.9%, 
 
 
 
5/13/22 (144A) 
6,630,815 
 
 Total Auto Manufacturers $ 134,906,065 
 
 Banks — 16.5% 
 
5,690,000(a)  
ABN AMRO Bank NV, 0.76% (3 Month USD LIBOR + 
 
 
 
57 bps), 8/27/21 (144A) 
$ 5,701,107 
5,650,000  
ABN AMRO Bank NV, 3.4%, 8/27/21 (144A) 
5,720,069 
9,450,000(a)  
Bank of America Corp., 0.753% (SOFRRATE + 
 
 
 
73 bps), 10/24/24 
9,493,470 
23,289,000(a)  
Bank of America Corp., 0.984% (3 Month USD LIBOR + 
 
 
 
79 bps), 3/5/24 
23,518,087 
5,237,000(a)  
Bank of America Corp., 1.218% (3 Month USD LIBOR + 
 
 
 
100 bps), 4/24/23 
5,281,686 
15,152,000(a)  
Bank of America Corp., 1.404% (3 Month USD LIBOR + 
 
 
 
118 bps), 10/21/22 
15,241,949 
2,082,000(a)  
Bank of America Corp., 1.643% (3 Month USD LIBOR + 
 
 
 
142 bps), 4/19/21 
2,083,150 
16,000,000(a)  
Bank of Montreal, 0.361% (SOFRRATE + 
 
 
 
35 bps), 12/8/23 
16,000,640 
3,185,000(a)  
Bank of Montreal, 0.69% (SOFRRATE + 
 
 
 
68 bps), 3/10/23 
3,212,391 
3,138,000(a)  
Bank of Nova Scotia, 0.664% (3 Month USD LIBOR + 
 
 
 
44 bps), 4/20/21 
3,138,672 
15,240,000(a)  
Banque Federative du Credit Mutuel SA, 0.954% 
 
 
 
(3 Month USD LIBOR + 73 bps), 7/20/22 (144A) 
15,352,533 
2,620,000(a)  
Banque Federative du Credit Mutuel SA, 1.184% 
 
 
 
(3 Month USD LIBOR + 96 bps), 7/20/23 (144A) 
2,663,968 
5,125,000  
Banque Federative du Credit Mutuel SA, 2.125%, 
 
 
 
11/21/22 (144A) 
5,266,684 
12,008,000(a)  
Barclays Plc, 1.624% (3 Month USD LIBOR + 
 
 
 
143 bps), 2/15/23 
12,097,767 
 
The accompanying notes are an integral part of these financial statements. 
58 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Banks — (continued) 
 
6,050,000(a)  
Barclays Plc, 1.85% (3 Month USD LIBOR + 
 
 
 
163 bps), 1/10/23 
$ 6,102,489 
4,490,000  
Barclays Plc, 3.2%, 8/10/21 
4,534,443 
18,956,000(a)  
BPCE SA, 1.402% (3 Month USD LIBOR + 122 bps), 
 
 
 
5/22/22 (144A) 
19,153,142 
7,030,000  
BPCE SA, 3.0%, 5/22/22 (144A) 
7,231,865 
18,400,000(a)  
Canadian Imperial Bank of Commerce, 0.41% 
 
 
 
(SOFRRATE + 40 bps), 12/14/23 
18,419,315 
5,890,000  
Capital One NA, 2.95%, 7/23/21 
5,923,534 
16,729,000(a)  
Citigroup, Inc., 1.178% (3 Month USD LIBOR + 
 
 
 
96 bps), 4/25/22 
16,865,294 
13,621,000(a)  
Citigroup, Inc., 1.246% (3 Month USD LIBOR + 
 
 
 
107 bps), 12/8/21 
13,699,820 
9,220,000(a)  
Citigroup, Inc., 1.392% (3 Month USD LIBOR + 
 
 
 
119 bps), 8/2/21 
9,253,345 
3,875,000(a)  
Cooperatieve Rabobank UA, 0.645% (3 Month USD 
 
 
 
LIBOR + 43 bps), 4/26/21 
3,876,172 
2,350,000(a)  
Cooperatieve Rabobank UA, 0.705% (3 Month USD 
 
 
 
LIBOR + 48 bps), 1/10/23 
2,362,819 
10,000,000(a)  
Credit Suisse AG, 0.412% (SOFRRATE + 39 bps), 2/2/24 
9,907,000 
6,340,000(a)  
Credit Suisse AG, 0.47% (SOFRRATE + 45 bps), 2/4/22 
6,343,247 
10,765,000(a)  
Credit Suisse Group AG, 1.384% (3 Month USD LIBOR + 
 
 
 
120 bps), 12/14/23 (144A) 
10,829,590 
22,617,000(a)  
Credit Suisse Group Funding Guernsey, Ltd., 2.513% 
 
 
 
(3 Month USD LIBOR + 229 bps), 4/16/21 
22,632,321 
10,770,000  
Credit Suisse Group Funding Guernsey, Ltd., 
 
 
 
3.45%, 4/16/21 
10,779,988 
6,457,000  
Danske Bank A/S, 2.7%, 3/2/22 (144A) 
6,589,669 
4,046,000  
Discover Bank, 3.2%, 8/9/21 
4,076,545 
5,000,000(a)  
Goldman Sachs Group, Inc., 0.556% (SOFRRATE + 
 
 
 
54 bps), 11/17/23 
4,994,717 
5,000,000(a)  
Goldman Sachs Group, Inc., 0.925% (3 Month USD 
 
 
 
LIBOR + 75 bps), 2/23/23 
5,040,734 
4,425,000(a)  
Goldman Sachs Group, Inc., 1.325% (3 Month USD 
 
 
 
LIBOR + 111 bps), 4/26/22 
4,427,527 
2,725,000(a)  
JPMorgan Chase & Co., 0.8% (3 Month USD LIBOR + 
 
 
 
61 bps), 6/18/22 
2,727,332 
11,800,000(a)  
JPMorgan Chase & Co., 0.948% (3 Month USD LIBOR + 
 
 
 
73 bps), 4/23/24 
11,898,294 
5,000,000(a)  
JPMorgan Chase & Co., 1.118% (3 Month USD LIBOR + 
 
 
 
90 bps), 4/25/23 
5,037,634 
18,025,000(a)  
JPMorgan Chase & Co., 1.276% (3 Month USD LIBOR + 
 
 
 
110 bps), 6/7/21 
18,041,205 
11,294,000(a)  
KeyBank NA, 0.35% (SOFRRATE + 34 bps), 1/3/24 
11,289,971 
2,905,000(a)  
KeyBank NA, 0.865% (3 Month USD LIBOR + 
 
 
 
66 bps), 2/1/22 
2,919,183 
21,000,000(a)  
Macquarie Bank, Ltd., 0.643% (3 Month USD LIBOR + 
 
 
 
45 bps), 8/6/21 (144A) 
21,028,955 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 59

 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Banks — (continued) 
 
2,968,000(a)  
Mitsubishi UFJ Financial Group, Inc., 0.865% (3 Month 
 
 
 
USD LIBOR + 65 bps), 7/26/21 
$ 2,973,595 
3,000,000(a)  
Mitsubishi UFJ Financial Group, Inc., 0.876% (3 Month 
 
 
 
USD LIBOR + 70 bps), 3/7/22 
3,014,838 
25,302,000(a)  
Mitsubishi UFJ Financial Group, Inc., 1.008% (3 Month 
 
 
 
USD LIBOR + 79 bps), 7/25/22 
25,490,044 
6,295,000(a)  
Mizuho Financial Group, Inc., 1.034% (3 Month USD 
 
 
 
LIBOR + 85 bps), 9/13/23 
6,346,538 
7,505,000(a)  
Mizuho Financial Group, Inc., 1.057% (3 Month USD 
 
 
 
LIBOR + 88 bps), 9/11/22 
7,575,442 
14,679,000(a)  
Mizuho Financial Group, Inc., 1.13% (3 Month USD 
 
 
 
LIBOR + 94 bps), 2/28/22 
14,782,502 
13,675,000  
Mizuho Financial Group, Inc., 2.632%, 4/12/21 (144A) 
13,681,223 
12,580,000(a)  
Morgan Stanley, 1.152% (3 Month USD LIBOR + 
 
 
 
93 bps), 7/22/22 
12,608,354 
12,114,000(a)  
PNC Bank NA, 0.672% (3 Month USD LIBOR + 
 
 
 
45 bps), 7/22/22 
12,128,941 
4,499,000(a)  
PNC Bank NA, 0.713% (3 Month USD LIBOR + 
 
 
 
50 bps), 7/27/22 
4,523,855 
22,000,000(a)  
Royal Bank of Canada, 0.33% (SOFRRATE + 
 
 
 
30 bps), 1/19/24 
21,968,980 
12,310,000(a)  
Royal Bank of Canada, 0.682% (3 Month USD LIBOR + 
 
 
 
47 bps), 4/29/22 
12,358,853 
4,800,000  
Royal Bank of Canada, 3.35%, 10/22/21 (144A) 
4,882,706 
9,220,000(a)  
Santander UK Plc, 0.811% (3 Month USD LIBOR + 
 
 
 
62 bps), 6/1/21 
9,229,127 
15,252,000(a)  
Skandinaviska Enskilda Banken AB, 0.829% (3 Month 
 
 
 
USD LIBOR + 65 bps), 12/12/22 (144A) 
15,374,082 
13,625,000  
Skandinaviska Enskilda Banken AB, 3.25%, 
 
 
 
5/17/21 (144A) 
13,675,276 
11,850,000(a)  
Standard Chartered Plc, 1.281% (SOFRRATE + 
 
 
 
125 bps), 10/14/23 (144A) 
11,979,732 
6,450,000(a)  
Standard Chartered Plc, 1.383% (3 Month USD LIBOR + 
 
 
 
120 bps), 9/10/22 (144A) 
6,476,823 
4,232,000(a)  
Sumitomo Mitsui Financial Group, Inc., 0.963% (3 Month 
 
 
 
USD LIBOR + 74 bps), 10/18/22 
4,263,907 
22,118,000(a)  
Sumitomo Mitsui Financial Group, Inc., 1.004% (3 Month 
 
 
 
USD LIBOR + 78 bps), 7/12/22 
22,284,366 
6,570,000  
Sumitomo Mitsui Financial Group, Inc., 2.058%, 7/14/21 
6,603,143 
5,265,000(a)  
Toronto-Dominion Bank, 0.721% (3 Month USD LIBOR + 
 
 
 
53 bps), 12/1/22 
5,304,423 
1,000,000(a)  
Toronto-Dominion Bank, 0.863% (3 Month USD LIBOR + 
 
 
 
64 bps), 7/19/23 
1,010,701 
1,035,000(a)  
Toronto-Dominion Bank, 1.237% (3 Month USD LIBOR + 
 
 
 
100 bps), 4/7/21 
1,035,064 
25,014,000(a)  
Truist Bank, 0.782% (3 Month USD LIBOR + 
 
 
 
59 bps), 5/17/22 
25,155,220 
5,800,000(a)  
UBS AG, 0.378% (SOFRRATE + 36 bps), 2/9/24 (144A) 
5,793,330 
 
The accompanying notes are an integral part of these financial statements.
60 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Banks — (continued) 
 
8,110,000  
UBS AG, 7.625%, 8/17/22 
$ 8,839,614 
16,208,000(a)  
UBS Group AG, 1.735% (3 Month USD LIBOR + 
 
 
 
153 bps), 2/1/22 (144A) 
16,414,443 
1,800,000(a)  
UBS Group AG, 2.014% (3 Month USD LIBOR + 
 
 
 
178 bps), 4/14/21 (144A) 
1,800,797 
15,218,000  
UBS Group AG, 3.0%, 4/15/21 (144A) 
15,229,783 
14,665,000(a)  
Wells Fargo & Co., 1.24% (3 Month USD LIBOR + 
 
 
 
103 bps), 7/26/21 
14,707,944 
5,332,000(a)  
Wells Fargo & Co., 1.328% (3 Month USD LIBOR + 
 
 
 
111 bps), 1/24/23 
5,372,427 
6,430,000  
Wells Fargo & Co., 4.6%, 4/1/21 
6,430,000 
6,430,000(a)  
Wells Fargo Bank NA, 0.81% (3 Month USD LIBOR + 
 
 
 
62 bps), 5/27/22 
6,435,793 
 
 Total Banks $ 736,510,189 
 
 Diversified Financial Services — 1.0% 
 
6,193,000(a)  
American Express Co., 0.717% (3 Month USD LIBOR + 
 
 
 
53 bps), 5/17/21 
$ 6,194,212 
12,490,000(a)  
American Express Co., 0.815% (3 Month USD LIBOR + 
 
 
 
61 bps), 8/1/22 
12,563,066 
1,400,000(a)  
Aviation Capital Group LLC, 0.882% (3 Month USD 
 
 
 
LIBOR + 67 bps), 7/30/21 (144A) 
1,398,538 
15,850,000(a)  
Capital One Financial Corp., 0.932% (3 Month USD 
 
 
 
LIBOR + 72 bps), 1/30/23 
15,964,253 
9,158,000(a)  
Charles Schwab Corp., 0.502% (3 Month USD LIBOR + 
 
 
 
32 bps), 5/21/21 
9,159,367 
 
 Total Diversified Financial Services $ 45,279,436 
 
 Electric — 2.0% 
 
6,440,000(a)  
American Electric Power Co., Inc., 0.685% (3 Month 
 
 
 
USD LIBOR + 48 bps), 11/1/23 
$ 6,449,366 
9,175,000(a)  
Dominion Energy, Inc., 0.714% (3 Month USD LIBOR + 
 
 
 
53 bps), 9/15/23 
9,186,861 
7,152,000(c)  
Dominion Energy, Inc., 2.715%, 8/15/21 
7,211,502 
17,130,000  
Dominion Energy, Inc., 2.75%, 1/15/22 
17,407,709 
39,321,000(a)  
Duke Energy Corp., 0.698% (3 Month USD LIBOR + 
 
 
 
50 bps), 5/14/21 (144A) 
39,341,152 
3,553,000  
Enel Finance International NV, 2.875%, 5/25/22 (144A) 
3,643,606 
6,600,000(a)  
NextEra Energy Capital Holdings, Inc., 0.55% 
 
 
 
(SOFRRATE + 54 bps), 3/1/23 
6,616,513 
 
 Total Electric $ 89,856,709 
 
 Gas — 0.2% 
 
6,225,000(a)  
Eastern Energy Gas Holdings LLC, 0.784% (3 Month 
 
 
 
USD LIBOR + 60 bps), 6/15/21 
$ 6,231,490 
 
 Total Gas $ 6,231,490 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 61 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Insurance — 0.5% 
 
1(d)  
Ambac Assurance Corp., 5.1% (144A) 
$ 1 
2(a)  
Ambac LSNI LLC, 6.0% (3 Month USD LIBOR + 
 
  
500 bps), 2/12/23 (144A) 
3,980,000  
Liberty Mutual Group, Inc., 5.0%, 6/1/21 (144A) 
4,007,777 
4,380,000(a)  
Metropolitan Life Global Funding I, 0.603% 
 
  
(SOFRRATE + 57 bps), 1/13/23 (144A) 
4,405,930 
4,531,000(a)  
New York Life Global Funding, 0.513% (3 Month USD 
 
  
LIBOR + 32 bps), 8/6/21 (144A) 
4,536,120 
9,350,000(a)  
Northwestern Mutual Global Funding, 0.34% 
 
  
(SOFRRATE + 33 bps), 3/25/24 (144A) 
9,354,855 
  Total Insurance $ 22,304,685 

 Machinery-Construction & Mining — 0.4% 
9,120,000(a)  
Caterpillar Financial Services Corp., 0.582% (3 Month 
 
  
USD LIBOR + 39 bps), 5/17/21 
$ 9,124,073 
9,091,000(a)  
Caterpillar Financial Services Corp., 0.929% (3 Month 
 
  
USD LIBOR + 74 bps), 5/13/22 
9,156,277 
  Total Machinery-Construction & Mining $ 18,280,350 
  Machinery-Diversified — 0.1% 
 
2,000(a)  
John Deere Capital Corp., 0.443% (3 Month USD 
 
  
LIBOR + 26 bps), 9/10/21 
$ 2,002 
4,500,000(a)  
John Deere Capital Corp., 0.576% (3 Month USD 
 
  
LIBOR + 40 bps), 6/7/21 
4,503,448 
  Total Machinery-Diversified $ 4,505,450 
  Media — 0.6% 
 
5,092,000(a)  
Comcast Corp., 0.642% (3 Month USD LIBOR + 
 
  
44 bps), 10/1/21 
$ 5,102,336 
4,570,000(a)  
NBCUniversal Enterprise, Inc., 0.638% (3 Month USD 
 
  
LIBOR + 40 bps), 4/1/21 (144A) 
4,570,000 
6,870,000(a)  
Walt Disney Co., 0.441% (3 Month USD LIBOR + 
 
  
25 bps), 9/1/21 
6,876,045 
9,910,000(a)  
Walt Disney Co., 0.581% (3 Month USD LIBOR + 
 
  
39 bps), 9/1/22 
9,952,035 
  Total Media $ 26,500,416 
  Oil & Gas — 1.2% 
 
2,775,000(a)  
BP Capital Markets Plc, 0.84% (3 Month USD LIBOR + 
 
  
65 bps), 9/19/22 
$ 2,787,292 
5,766,000(a)  
BP Capital Markets Plc, 1.06% (3 Month USD LIBOR + 
 
  
87 bps), 9/16/21 
5,786,361 
7,045,000  
Canadian Natural Resources, Ltd., 3.45%, 11/15/21 
7,120,386 
2,295,000(a)  
Chevron Corp., 0.714% (3 Month USD LIBOR + 
 
  
53 bps), 3/3/22 
2,304,043 
16,885,000(a)  
Chevron Corp., 1.103% (3 Month USD LIBOR + 
 
  
90 bps), 5/11/23 
17,158,366 
11,405,000(a)  
Exxon Mobil Corp., 0.524% (3 Month USD LIBOR + 
 
  
33 bps), 8/16/22 
11,442,261 
 
The accompanying notes are an integral part of these financial statements.
62 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Oil & Gas — (continued) 
 
7,200,000(a)  
Valero Energy Corp., 1.334% (3 Month USD LIBOR + 
 
 
 
115 bps), 9/15/23 
$ 7,224,376 
 
 Total Oil & Gas $ 53,823,085 
 
 Pharmaceuticals — 2.3% 
 
21,467,000(a)  
AbbVie, Inc., 0.532% (3 Month USD LIBOR + 
 
 
 
35 bps), 5/21/21 
$ 21,474,111 
7,900,000(a)  
AbbVie, Inc., 0.832% (3 Month USD LIBOR + 
 
 
 
65 bps), 11/21/22 
7,948,521 
7,317,000  
AbbVie, Inc., 5.0%, 12/15/21 
7,462,541 
5,890,000  
AmerisourceBergen Corp., 0.737%, 3/15/23 
5,894,938 
19,060,000(a)  
Bayer US Finance II LLC, 0.831% (3 Month USD LIBOR + 
 
 
 
63 bps), 6/25/21 (144A) 
19,074,293 
12,890,000(a)  
Becton Dickinson & Co., 1.206% (3 Month USD LIBOR + 
 
 
 
103 bps), 6/6/22 
13,011,320 
13,126,000(a)  
Cardinal Health, Inc., 0.954% (3 Month USD LIBOR + 
 
 
 
77 bps), 6/15/22 
13,220,717 
15,430,000(a)  
Zoetis, Inc., 0.622% (3 Month USD LIBOR + 
 
 
 
44 bps), 8/20/21 
15,449,791 
 
 Total Pharmaceuticals $ 103,536,232 
 
 Pipelines — 0.4% 
 
15,605,000(a)  
MPLX LP, 1.285% (3 Month USD LIBOR + 
 
 
 
110 bps), 9/9/22 
$ 15,613,087 
 
 Total Pipelines $ 15,613,087 
 
 Retail — 0.2% 
 
6,365,000(a)  
7-Eleven, Inc., 0.645% (3 Month USD LIBOR + 
 
 
 
45 bps), 8/10/22 (144A) 
$ 6,371,529 
 
 Total Retail $ 6,371,529 
 
 Telecommunications — 0.5% 
 
17,944,000(a)  
AT&T, Inc., 1.191% (3 Month USD LIBOR + 
 
 
 
95 bps), 7/15/21 
$ 17,990,538 
5,471,000(a)  
Verizon Communications, Inc., 0.51% (SOFRRATE + 
 
 
 
50 bps), 3/22/24 
5,485,707 
 
 Total Telecommunications $ 23,476,245 
 
 Trucking & Leasing — 0.4% 
 
5,010,000(a)  
GATX Corp., 0.915% (3 Month USD LIBOR + 
 
 
 
72 bps), 11/5/21 
$ 5,026,815 
10,121,000  
Penske Truck Leasing Co. LP/PTL Finance Corp., 
 
 
 
3.375%, 2/1/22 (144A) 
10,307,645 
2,870,000  
Penske Truck Leasing Co. LP/PTL Finance Corp., 
 
 
 
3.65%, 7/29/21 (144A) 
2,891,805 
 
 Total Trucking & Leasing $ 18,226,265 
 
 TOTAL CORPORATE BONDS 
 
 
 
(Cost $1,311,455,495) 
$1,315,471,908 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 63
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 INSURANCE-LINKED SECURITIES — 2.2% 
 
 
 of Net Assets# 
 
 
 Event-Linked Bonds — 1.8% 
 
 
 Earthquakes – California — 0.1% 
 
1,000,000(a)  Ursa Re, 5.245% (3 Month U.S. Treasury Bill + 
 
 
 523 bps), 9/24/21 (144A) $ 1,001,100 
750,000(a)  Ursa Re, 5.765% (3 Month U.S. Treasury Bill + 
 
 
 575 bps), 12/10/22 (144A) 759,450 
4,000,000(a)  Ursa Re II, 3.765% (3 Month U.S. Treasury Bill + 
 
 
 375 bps), 12/7/23 (144A) 4,088,400 
 
 
 
$ 5,848,950 
 
 Earthquakes – Japan — 0.0%† 
 
750,000(a)  Kizuna Re II, 1.89% (3 Month U.S. Treasury Bill + 
 
 
 188 bps), 4/11/23 (144A) $ 751,650 
250,000(a)  Kizuna Re II, 2.515% (3 Month U.S. Treasury Bill + 
 
 
 250 bps), 4/11/23 (144A) 250,800 
700,000(a)  Nakama Re, 2.2% (6 Month USD LIBOR + 220 bps), 
 
 
 10/13/21 (144A) 700,770 
 
 
 
$ 1,703,220 
 
 Earthquakes – Mexico — 0.0%† 
 
500,000(a)  International Bank for Reconstruction & Development, 
 
 
 3.604% (3 Month USD LIBOR + 350 bps), 
 
 
 
3/13/24 (144A) 
$ 505,500 
 
 Earthquakes – U.S. — 0.0%† 
 
1,000,000(a)  Torrey Pines Re Pte, 1.75% (3 Month U.S. Treasury Bill + 
 
 
 
400 bps), 6/7/24 (144A) 
$ 999,900 
 
 Health – U.S. — 0.1% 
 
3,500,000(a)  Vitality Re X, 1.765% (3 Month U.S. Treasury Bill + 
 
 
 175 bps), 1/10/23 (144A) $ 3,482,500 
1,750,000(a)  Vitality Re X, 2.015% (3 Month U.S. Treasury Bill + 
 
 
 200 bps), 1/10/23 (144A) 1,715,000 
 
 
 
$ 5,197,500 
 
 Inland Flood – U.S. — 0.0%† 
 
500,000(a)  FloodSmart Re, 11.83% (1 Month U.S. Treasury Bill + 
 
 
 
1,183 bps), 3/7/22 (144A) 
$ 499,950 
 
 Multiperil – Florida — 0.0%† 
 
250,000(a)  Sanders Re II, 5.515% (3 Month U.S. Treasury Bill + 
 
 
 
550 bps), 6/7/23 (144A) 
$ 255,000 
 
 Multiperil – Japan — 0.0%† 
 
250,000(a)  Akibare Re, 2.102% (3 Month USD LIBOR + 190 bps), 
 
 
 4/7/22 (144A) $ 251,000 
500,000(a)  Akibare Re, 2.102% (3 Month USD LIBOR + 190 bps), 
 
 
 4/7/22 (144A) 502,250 
    $ 753,250
 
The accompanying notes are an integral part of these financial statements.
64 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Multiperil – U.S. — 0.6% 
 
1,500,000(a)  
Bonanza Re, 4.765% (3 Month U.S. Treasury Bill + 
 
 
 
475 bps), 2/20/24 (144A) 
$ 1,513,500 
250,000(a)  
Bowline Re, Series Series 2018-1, 4.775% (3 Month U.S. 
 
 
 
Treasury Bill + 476 bps), 5/23/22 (144A) 
253,025 
625,000(a)  
Caelus Re V, 0.515% (1 Month U.S. Treasury Bill + 
 
 
 
50 bps), 6/5/24 (144A) 
50,000 
500,000(a)  
Caelus Re V, 3.205% (3 Month U.S. Treasury Bill + 
 
 
 
319 bps), 6/7/21 (144A) 
350,000 
750,000(a)  
Caelus Re V, 4.045% (3 Month U.S. Treasury Bill + 
 
 
 
403 bps), 6/7/21 (144A) 
375,000 
750,000(a)  
Caelus Re VI, 5.515% (3 Month U.S. Treasury Bill + 
 
 
 
550 bps), 6/7/24 (144A) 
769,650 
4,500,000(a)  
Easton Re Pte, 4.015% (3 Month U.S. Treasury Bill + 
 
 
 
400 bps), 1/8/24 (144A) 
4,529,250 
500,000(a)  
Fortius Re II, 3.42% (6 Month USD LIBOR + 
 
 
 
342 bps), 7/7/21 (144A) 
502,000 
1,750,000(a)  
Four Lakes Re, 7.015% (3 Month U.S. Treasury Bill + 
 
 
 
700 bps), 1/5/24 (144A) 
1,739,675 
500,000(a)  
Herbie Re, 6.265% (3 Month U.S. Treasury Bill + 
 
 
 
625 bps), 1/28/25 (144A) 
531,300 
250,000(a)  
Kilimanjaro Re, 4.978% (3 Month USD LIBOR + 
 
 
 
494 bps), 5/6/22 (144A) 
251,575 
350,000(a)  
Kilimanjaro II Re, 6.3% (6 Month USD LIBOR + 
 
 
 
630 bps), 4/20/21 (144A) 
350,525 
1,700,000(a)  
Kilimanjaro II Re, 7.91% (6 Month USD LIBOR + 
 
 
 
791 bps), 4/21/22 (144A) 
1,716,150 
2,100,000(a)  
Residential Reinsurance 2017, 3.285% (3 Month U.S. 
 
 
 
Treasury Bill + 327 bps), 6/6/21 (144A) 
2,091,180 
2,900,000(a)  
Residential Reinsurance 2017, 5.945% (3 Month U.S. 
 
 
 
Treasury Bill + 593 bps), 12/6/21 (144A) 
2,906,380 
1,250,000(a)  
Residential Reinsurance 2018, 3.375% (3 Month U.S. 
 
 
 
Treasury Bill + 336 bps), 6/6/22 (144A) 
1,231,875 
500,000(a)  
Residential Reinsurance 2019, 4.665% (3 Month U.S. 
 
 
 
Treasury Bill + 465 bps), 6/6/23 (144A) 
493,350 
500,000(a)  
Residential Reinsurance 2020, 5.515% (3 Month U.S. 
 
 
 
Treasury Bill + 550 bps), 6/6/24 (144A) 
502,700 
1,500,000(a)  
Residential Reinsurance 2020, 6.265% (3 Month U.S. 
 
 
 
Treasury Bill + 625 bps), 12/6/24 (144A) 
1,520,250 
250,000(a)  
Sanders Re, 2.93% (6 Month USD LIBOR + 293 bps), 
 
 
 
12/6/21 (144A) 
249,275 
1,000,000(a)  
Spectrum Capital, Ltd., 5.75% (6 Month USD LIBOR + 
 
 
 
575 bps), 6/8/21 (144A) 
1,004,600 
1,000,000(a)  
Sussex Capital UK Pcc Ltd., 7.765% (3 Month U.S. 
 
 
 
Treasury Bill + 775 bps), 1/8/25 (144A) 
1,019,000 
3,350,000(a)  
Tailwind Re, 7.665% (3 Month U.S. Treasury Bill + 
 
 
 
765 bps), 1/8/22 (144A) 
3,384,170 
 
 
 
$ 27,334,430 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 65
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Multiperil – U.S. & Canada — 0.1% 
 
2,500,000(a)  
Hypatia, Ltd., 6.763% (3 Month U.S. Treasury Bill + 
 
 
 
675 bps), 6/7/23 (144A) 
$ 2,648,750 
1,000,000(a)  
Hypatia, Ltd., 9.763% (3 Month U.S. Treasury Bill + 
 
 
 
975 bps), 6/7/23 (144A) 
1,064,000 
 
 
 
$ 3,712,750 
 
 Multiperil – U.S. Regional — 0.1% 
 
1,750,000(a)  
First Coast Re 2017-1 Ltd., 4.19% (3 Month U.S. 
 
 
 
Treasury Bill + 419 bps), 6/7/21 (144A) 
$ 1,755,075 
700,000(a)  
First Coast Re II Pte, 5.66% (3 Month U.S. Treasury 
 
 
 
Bill + 566 bps), 6/7/23 (144A) 
708,120 
1,250,000(a)  
Long Point Re III, 2.765% (3 Month U.S. Treasury Bill + 
 
 
 
275 bps), 6/1/22 (144A) 
1,253,375 
400,000(a)  
Matterhorn Re, 5.015% (3 Month U.S. Treasury Bill + 
 
 
 
500 bps), 1/8/24 (144A) 
390,360 
 
 
 
$ 4,106,930 
 
 Multiperil – Worldwide — 0.1% 
 
500,000(a)  
Kendall Re, 5.283% (3 Month USD LIBOR + 525 bps), 
 
 
 
5/6/21 (144A) 
$ 499,250 
1,500,000(a)  
Northshore Re II, 5.765% (3 Month U.S. Treasury Bill + 
 
 
 
575 bps), 1/8/24 (144A) 
1,536,000 
 
 
 
$ 2,035,250 
 
 Pandemic – U.S. — 0.1% 
 
3,000,000(a)  
Vitality Re X, 1.515% (3 Month U.S. Treasury Bill + 
 
 
 
150 bps), 1/9/24 (144A) 
$ 2,925,000 
1,250,000(a)  
Vitality Re XI, 1.815% (3 Month U.S. Treasury Bill + 
 
 
 
180 bps), 1/9/24 (144A) 
1,218,125 
 
 
 
$ 4,143,125 
 
 Windstorm – Florida — 0.1% 
 
2,500,000(a)  
Integrity Re, 4.05% (3 Month USD LIBOR + 
 
 
 
405 bps), 6/10/22 (144A) 
$ 2,498,000 
 
 Windstorm – Japan — 0.0%† 
 
1,500,000(a)  
Aozora Re, 2.0% (6 Month USD LIBOR + 200 bps), 
 
 
 
4/7/21 (144A) 
$ 1,500,000 
 
 Windstorm – Mexico — 0.0%† 
 
500,000  
International Bank for Reconstruction & Development, 
 
 
 
6.64%, 3/13/24 
$ 505,500 
 
 Windstorm – Texas — 0.1% 
 
1,000,000(a)  
Alamo Re, 3.415% (3 Month U.S. Treasury Bill + 
 
 
 
340 bps), 6/7/21 (144A) 
$ 1,001,200 
2,500,000(a)  
Alamo Re II, 5.765% (1 Month U.S. Treasury Bill + 
 
 
 
575 bps), 6/8/23 (144A) 
2,613,750 
 
 
 
$ 3,614,950 
 
The accompanying notes are an integral part of these financial statements.
66 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Windstorm – U.S. — 0.1% 
 
2,000,000(a)  
Bonanza Re, 4.765% (3 Month U.S. Treasury Bill + 
 
  
475 bps), 12/23/24 (144A) 
$ 2,017,600 
250,000(a)  
Bowline Re, 8.865% (3 Month U.S. Treasury Bill + 
 
  
885 bps), 3/20/23 (144A) 
256,275 
  
 
$ 2,273,875 
  Windstorm – U.S. Regional — 0.3% 
 
2,500,000  
Matterhorn Re, 12/7/21 (144A) 
$ 2,330,750 
1,500,000(a)  
Matterhorn Re, 4.386% (3 Month USD LIBOR + 
 
  
425 bps), 12/7/22 (144A) 
1,504,350 
3,000,000(a)  
Matterhorn Re, 5.636% (3 Month USD LIBOR + 
 
  
550 bps), 12/7/22 (144A) 
3,012,000 
1,500,000(a)  
Matterhorn Re, 6.265% (3 Month U.S. Treasury Bill + 
 
  
625 bps), 12/7/21 (144A) 
1,513,200 
250,000(a)  
Matterhorn Re, 7.015% (3 Month U.S. Treasury Bill + 
 
  
700 bps), 12/7/21 (144A) 
255,325 
2,250,000(a)  
Matterhorn Re, 10.015% (3 Month U.S. Treasury Bill + 
 
  
1,000 bps), 12/7/21 (144A) 
2,320,875 
2,000,000(a)  
Matterhorn Re 2020-1, 7.515% (3 Month U.S. Treasury 
 
  
Bill + 750 bps), 12/7/21 (144A) 
2,012,800 
  
 
$ 12,949,300 
  Total Event-Linked Bonds $ 80,437,380 
 
Face  
 
 
Amount  
 
 
USD ($)  
 
 
  Collateralized Reinsurance — 0.3% 
 
  Multiperil – Massachusetts — 0.1% 
 
3,000,000+(e)(f)  
Denning Re, 7/31/24 
$ 3,003,004 
  Multiperil – U.S. — 0.1% 
 
500,000+(f)  
Dingle Re 2019, 2/1/22 
$ 10,263 
250,000+(e)(f)  
Dingle Re 2020, 12/31/21 
258,623 
4,000,000+(e)(f)  
Port Royal Re 2019, 5/31/21 
4,179,067 
  
 
$ 4,447,953 
  Multiperil – U.S. Regional — 0.1% 
 
2,750,000+(e)(f)  
Ailsa Re 2019, 6/30/21 
$ 2,915,473 
  Multiperil – Worldwide — 0.0%† 
 
1,000,000+(e)(f)  
Cypress Re 2017, 1/31/22 
$ 100 
24,000+(f)  
Limestone Re 2016-1, 8/31/21 
1,999 
40,000+(f)  
Limestone Re 2016-1, 8/31/21 
3,332 
223,000+(e)(f)  
Limestone Re, 2019-2, 3/1/23 (144A) 
307,784 
2,500,000+((e)(f)  
Resilience Re, 5/1/21 
250 
2,000,000+(e)(f)  
Resilience Re, 10/6/21 (144A) 
200 
  
 
$ 313,665 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 67
 
Schedule of Investments | 3/31/21 (continued)
    
Face  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Windstorm – Florida — 0.0%† 
 
2,000,000+(e)(f)  
Formby Re 2018, 2/28/22 
$ 278,387 
800,000+(e)(f)  
Portrush Re 2017, 6/15/21 
510,480 
  
 
$ 788,867 
  Windstorm – U.S. Regional — 0.0%† 
 
500,000+(e)(f)  
Oakmont Re 2017, 4/30/21 
$ 14,700 
  Total Collateralized Reinsurance $ 11,483,662 
  Reinsurance Sidecars — 0.1% 
 
  Multiperil – U.S. — 0.0%† 
 
2,000,000+(e)(f)  
Carnoustie Re 2017, 11/30/21 
$ 263,600 
1,100,000+(f)  
Carnoustie Re 2019, 12/31/22 
2,090 
1,500,000+(e)(f)  
Castle Stuart Re 2018, 12/1/21 
46,874 
2,000,000+(e)(g)  
Harambee Re 2018, 12/31/21 
7,200 
4,000,000+(g)  
Harambee Re 2019, 12/31/22 
33,600 
  
 
$ 353,364 
  Multiperil – Worldwide — 0.1% 
 
2,000+(f)  
Alturas Re 2019-1, 3/10/23 (144A) 
$ 9,146 
36,448+(g)  
Alturas Re 2019-2, 3/10/22 
96,802 
2,500,000+(e)(f)  
Bantry Re 2016, 3/31/22 
201,500 
2,000,000+(e)(f)  
Bantry Re 2017, 3/31/22 
116,882 
2,000,000+(e)(f)  
Bantry Re 2018, 12/31/21 
22,800 
4,000,000+(e)(f)  
Bantry Re 2019, 12/31/22 
135,855 
1,250,000+(e)(f)  
Berwick Re 2017-1, 2/1/22 
41,375 
5,120,164+(e)(f)  
Berwick Re 2018-1, 12/31/21 
491,956 
3,658,035+(e)(f)  
Berwick Re 2019-1, 12/31/22 
437,135 
1,500,000+(g)  
Blue Lotus Re 2018, 12/31/21 
46,050 
75,000+(f)  
Eden Re II, 3/22/22 (144A) 
61,127 
113,405+(f)  
Eden Re II, 3/22/22 (144A) 
89,565 
4,000+(f)  
Eden Re II, 3/22/23 (144A) 
21,633 
35,797+(f)  
Eden Re II, 3/22/23 (144A) 
207,090 
1,300,000+(e)(f)  
Gleneagles Re 2016, 11/30/21 
40,560 
2,118,314+(e)(f)  
Gullane Re 2018, 12/31/21 
361,093 
2,000+(f)  
Limestone Re 2018, 3/1/22 
– 
500,000+(g)  
Lion Rock Re 2019, 1/31/22 
20,250 
4,000,000+(e)(g)  
Lorenz Re 2018, 7/1/21 
42,800 
2,744,544+(e)(g)  
Lorenz Re 2019, 6/30/22 
128,994 
3,000,000+(e)(f)  
Merion Re 2018-2, 12/31/21 
496,500 
977,820+(g)  
NCM Re 2019, 12/31/22 
92,536 
1,500,000+(f)  
Pangaea Re 2016-2, 11/30/21 
2,675 
2,000,000+(e)(f)  
Pangaea Re 2018-1, 12/31/21 
42,109 
4,000,000+(e)(f)  
Pangaea Re 2018-3, 7/1/22 
82,974 
2,800,000+(e)(f)  
Pangaea Re 2019-1, 2/1/23 
58,345 
2,941,254+(e)(f)  
Pangaea Re 2019-3, 7/1/23 
105,800 
 
The accompanying notes are an integral part of these financial statements.
68 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Face  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Multiperil – Worldwide — (continued) 
 
2,400,000+(e)(f)  Sector Re V, 12/1/23 (144A) $ 562,702 
1,861+(f)  Sector Re V, 3/1/24 (144A) 31,036 
800,000+(e)(f)  Sector Re V, 3/1/24 (144A) 450,657 
160,000+(e)(f)  Sector Re V, 12/1/24 (144A) 379,947 
1,250,000+(e)(f)  St. Andrews Re 2017-1, 2/1/22 84,750 
1,737,984+(e)(f)  St. Andrews Re 2017-4, 6/1/21 171,018 
750,000+(e)(g)  Thopas Re 2018, 12/31/21 4,725 
3,000,000+(e)(g)  Thopas Re 2019, 12/31/22 125,400 
2,000,000+(e)(f)  Versutus Re 2018, 12/31/21 6,600 
1,765,095+(f)  Versutus Re 2019-A, 12/31/21 32,831 
1,434,906+(f)  Versutus Re 2019-B, 12/31/21 26,689 
750,000+(e)(g)  Viribus Re 2018, 12/31/21 — 
2,500,000+(e)(g)  Viribus Re 2019, 12/31/22 103,250 
1,724,784+(e)(f)  Woburn Re 2018, 12/31/21 126,599 
809,418+(e)(f)  Woburn Re 2019, 12/31/22 239,345 
  
 
$ 5,799,101 
  Total Reinsurance Sidecars $ 6,152,465 
 
 TOTAL INSURANCE-LINKED SECURITIES 
 
 
 
(Cost $100,160,989) 
$ 98,073,507 
 
Principal  
 
 
Amount  
 
 
USD ($)  
 
 
 
 MUNICIPAL BOND — 0.0%† of Net 
 
 Assets(h) 
 
 Municipal Student Loan — 0.0%† 
 
29,549(a) Louisiana Public Facilities Authority, Student Loan 
 
 Backed, Series A, 1.118% (3 Month USD LIBOR + 
 
 90 bps), 4/26/27 $ 29,598 
 Total Municipal Student Loan $ 29,598 
 TOTAL MUNICIPAL BOND 
 
 
(Cost $29,668) 
$ 29,598 
 SENIOR SECURED FLOATING RATE LOAN 
 

 INTERESTS — 5.0% of Net Assets*(a)
 
 Aerospace & Defense — 0.1% 
 
2,400,024 American Airlines, Inc., 2018 Replacement Term 
 
 Loan, 1.859% (LIBOR + 175 bps), 6/27/25 $ 2,127,451 
995,000 MAG DS Corp., Initial Term Loan, 6.5% (LIBOR + 
 
 550 bps), 4/1/27 977,588 
736,875 MRO Holdings, Inc., Initial Term Loan, 5.203% (LIBOR + 
 
 500 bps), 6/4/26 716,611 
797,086(i) Peraton Corp., Additional Term Loan, 2/1/28 798,417 
452,914 Peraton Corp., First Lien Term B Loan, 4.5% (LIBOR + 
 
 375 bps), 2/1/28 453,103 

 The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 69
 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Aerospace & Defense — (continued) 
 
997,500  
Spirit Aerosystems, Inc. (fka Mid-Western Aircraft 
 
  
Systems, Inc & Onex Wind Finance LP.), Initial Term 
 
  
Loan, 6.0% (LIBOR + 525 bps), 1/15/25 
$ 1,006,228 
85,247  
United Airlines, Inc., Refinanced Term Loan, 1.865% 
 
  
(LIBOR + 175 bps), 4/1/24 
83,009 
  Total Aerospace & Defense $ 6,162,407 
  All Other — 0.0%† 
 
1,000,000(i)  
Adevinta ASA Facility B2, Term Loan, 10/22/27 
$ 1,002,031 
  Total All Other $ 1,002,031 
  Automobile — 0.2% 
 
2,000,000  
Dana, Inc., 2018 New Term Loan B Advance, 2.359% 
 
  
(LIBOR + 225 bps), 2/27/26 
$ 1,996,750 
2,000,000  
Goodyear Tire & Rubber Co., Second Lien Term Loan, 
 
  
2.12% (LIBOR + 200 bps), 3/3/25 
1,951,250 
1,166,667  
Highline Aftermarket Acquisition LLC, First Lien Initial 
 
  
Term Loan, 5.25% (LIBOR + 450 bps), 11/9/27 
1,171,042 
1,989,744  
Navistar, Inc., Tranche B Term Loan, 3.62% (LIBOR + 
 
  
350 bps), 11/6/24 
1,992,977 
291,667  
Visteon Corp., New Term Loan, 1.869% (LIBOR + 
 
  
175 bps), 3/25/24 
289,965 
265,844  
Wabash National Corp., Initial Term Loan, 4.0% 
 
  
(LIBOR + 325 bps), 9/28/27 
266,176 
  Total Automobile $ 7,668,160 
  Automotive — 0.0%† 
 
498,709  
IXS Holdings, Inc., Initial Term Loan, 5.0% (LIBOR + 
 
  
425 bps), 3/5/27 
$ 499,644 
1,000,000(i)  
Trinseo Materials Operating SCA (fka Styron S.a.r.l), 
 
  
Term Loan, 3/17/28 
991,250 
  Total Automotive $ 1,490,894 
  Beverage, Food & Tobacco — 0.0%† 
 
985,000  
US Foods, Inc. (aka U.S. Foodservice, Inc.), Incremental 
 
  
B-2019 Term Loan, 2.109% (LIBOR + 
 
  
200 bps), 9/13/26 
$ 967,558 
  Total Beverage, Food & Tobacco $ 967,558 
  Broadcasting & Entertainment — 0.1% 
 
1,087,297  
Gray Television, Inc., Term B-2 Loan, 2.365% (LIBOR + 
 
  
225 bps), 2/7/24 
$ 1,082,114 
4,000,001  
Gray Television, Inc., Term C Loan, 2.615% (LIBOR + 
 
  
250 bps), 1/2/26 
3,976,877 
  Total Broadcasting & Entertainment $ 5,058,991 
  Building Materials — 0.1% 
 
1,091,190  
Circor International, Inc., New Term Loan, 4.25% 
 
  
(LIBOR + 325 bps), 12/11/24 
$ 1,080,505 
 
The accompanying notes are an integral part of these financial statements.
70 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Building Materials — (continued) 
 
500,000(i)  
Cornerstone Building Brands, Inc., Term 
 
 
 
Loan B, 4/12/28 
$ 498,125 
2,711,932  
Summit Materials LLC, New Term Loan, 2.109% 
 
 
 
(LIBOR + 200 bps), 11/21/24 
2,707,411 
 
 Total Building Materials $ 4,286,041 
 
 Buildings & Real Estate — 0.1% 
 
1,321,521  
Beacon Roofing Supply, Inc., Initial Term Loan, 2.359% 
 
 
 
(LIBOR + 225 bps), 1/2/25 
$ 1,316,359 
1,250,000  
Potters Industries LLC, Initial Term Loan, 4.203% 
 
 
 
(LIBOR + 400 bps), 12/14/27 
1,253,125 
2,100,000  
VICI Properties 1 LLC, Term B Loan, 1.861% (LIBOR + 
 
 
 
175 bps), 12/20/24 
2,078,563 
632,307  
WireCo WorldGroup, Inc. (WireCo WorldGroup 
 
 
 
Finance LP), First Lien Initial Term Loan, 6.0% (LIBOR + 
 
 
 
500 bps), 9/29/23 
618,476 
 
 Total Buildings & Real Estate $ 5,266,523 
 
 Chemicals — 0.2% 
 
2,044,875  
Avantor Funding, Inc., Incremental B-4 Dollar Term 
 
 
 
Loan, 3.25% (LIBOR + 225 bps), 11/8/27 
$ 2,048,198 
1,984,887  
Element Solutions, Inc. (Macdermid, Inc.), Tranche 
 
 
 
B-1 Term Loan, 2.109% (LIBOR + 200 bps), 1/31/26 
1,976,824 
1,000,000  
Gemini HDPE LLC, 2027 Advance, 3.5% (LIBOR + 
 
 
 
300 bps), 12/31/27 
998,750 
1,000,000  
INEOS Styrolution Group GmbH, 2026 Tranche B Dollar 
 
 
 
Term Loan, 3.25% (LIBOR + 275 bps), 1/29/26 
997,750 
2,478,043  
Tronox Finance LLC, First Lien Refinancing Term Loan, 
 
 
 
2.648% (LIBOR + 250 bps), 3/10/28 
2,467,201 
1,500,000(i)  
W. R. Grace & Co., USD Term Loan B, 3/30/28 
1,494,375 
 
 Total Chemicals $ 9,983,098 
 
 Chemicals, Plastics & Rubber — 0.2% 
 
2,382,866  
Axalta Coating Systems Dutch Holding B BV (Axalta 
 
 
 
Coating Systems U.S. Holdings, Inc.), Term B-3 Dollar 
 
 
 
Loan, 1.953% (LIBOR + 175 bps), 6/1/24 
$ 2,374,781 
6,405,298  
Berry Global, Inc. (fka Berry Plastics Corp), Term Z 
 
 
 
Loan, 1.898% (LIBOR + 175 bps), 7/1/26 
6,363,247 
364,463  
Pactiv Evergreen, Inc., Tranche B-1 US Term Loan, 
 
 
 
2.859% (LIBOR + 275 bps), 2/5/23 
363,865 
1,278,786  
PQ Corp., Third Amendment Tranche B-1 Term Loan, 
 
 
 
2.462% (LIBOR + 225 bps), 2/7/27 
1,271,592 
57  
Twist Beauty International Holdings S.A., Facility B2, 
 
 
 
4.0% (LIBOR + 300 bps), 4/22/24 
55 
 
 Total Chemicals, Plastics & Rubber $ 10,373,540 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 71
 
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Computers & Electronics — 0.3% 
 
2,600,000  
Ahead DB Holdings LLC, First Lien Initial Term Loan, 
 
 
 
6.0% (LIBOR + 500 bps), 10/18/27 
$ 2,608,125 
500,000  
athenahealth, Inc., First Lien Term B-1 Loan, 4.453% 
 
 
 
(LIBOR + 425 bps), 2/11/26 
501,875 
580,000  
Celestica, Inc., Incremental Term B-2 Loan, 2.609% 
 
 
 
(LIBOR + 250 bps), 6/27/25 
579,275 
500,000  
Endurance International Group Holdings, Inc., Initial 
 
 
 
Term Loan, 4.25% (LIBOR + 350 bps), 2/10/28 
498,646 
750,000  
Energizer Holdings, Inc., 2020 Term Loan, 2.75% 
 
 
 
(LIBOR + 225 bps), 12/22/27 
749,414 
2,543,625  
LogMeIn, Inc., First Lien Initial Term Loan, 4.854% 
 
 
 
(LIBOR + 475 bps), 8/31/27 
2,540,672 
3,432,330  
NCR Corp., Initial Term Loan, 2.72% (LIBOR + 
 
 
 
250 bps), 8/28/26 
3,415,168 
1,090,000  
Pitney Bowes, Inc., Refinancing Tranche B Term Loan, 
 
 
 
4.11% (LIBOR + 400 bps), 3/17/28 
1,089,546 
 
 Total Computers & Electronics $ 11,982,721 
 
 Construction & Building — 0.0%† 
 
500,000  
Pike Corp., 2028 Initial Term Loan, 3.13% (LIBOR + 
 
 
 
300 bps), 1/21/28 
$ 499,375 
 
 Total Construction & Building $ 499,375 
 
 Consumer Durable — 0.0%† 
 
1,625,000  
ADS Tactical, Inc., Initial Term Loan, 6.75% (LIBOR + 
 
 
 
575 bps), 3/19/26 
$ 1,616,875 
 
 Total Consumer Durable $ 1,616,875 
 
 Consumer Services — 0.0%† 
 
930,513  
Prime Security Services Borrower LLC (aka Protection 1 
 

 Security Solutions), First Lien 2021 Refinancing 
 
 
Term B-1 Loan, 3.5% (LIBOR + 
 
 
 
275 bps), 9/23/26 
$ 927,190 
 
 Total Consumer Services $ 927,190 
 
 Diversified & Conglomerate Manufacturing — 0.0%† 
 
904,422  
Delos Finance S.a.r.l., New Term Loan, 3.200% 
 
 
 
(LIBOR + 175 bps), 10/6/23 
$ 903,787 
 
 Total Diversified & Conglomerate Manufacturing $ 903,787 

 Diversified & Conglomerate Service — 0.2% 
997,500  
Albany Molecular Research, Inc., First Lien 2020 Term 
 
 
 
Loan, 4.5% (LIBOR + 350 bps), 8/30/24 
$ 1,000,305 
1,980,769  
Avis Budget Car Rental LLC, New Tranche B Term 
 
 
 
Loan, 2.36% (LIBOR + 225 bps), 8/6/27 
1,937,234 
952,156  
Change Healthcare Holdings LLC, Closing Date Term 
 
 
 
Loan, 3.5% (LIBOR + 250 bps), 3/1/24 
952,037 
36,364(i)  
Convergint Technologies LLC, Delayed Draw Term 
 
 
 
Loan, 3/18/28 
50,191 
 
The accompanying notes are an integral part of these financial statements.
72 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Diversified & Conglomerate Service — (continued) 
 
173,636(i)  
Convergint Technologies LLC, Term Loan, 3/18/28 
$ 172,877 
461,273  
DTI Holdco, Inc., Replacement B-1 Term Loan, 5.75% 
 
  
(LIBOR + 475 bps), 9/29/23 
444,840 
1,000,000(i)  
Edelman Financial Center LLC (fka Flight Debt Merger 
 
  
Sub, Inc.), First Lien 2021 Initial Term Loan, 4/7/28 
995,940 
1,930,000  
Iqvia, Inc. (Quintiles IMS), Incremental Term B-2 Dollar 
 
  
Loan, 1.859% (LIBOR + 175 bps), 1/17/25 
1,921,556 
1,475,298  
Outfront Media Capital LLC (Outfront Media Capital 
 
   Corp.), Extended Term Loan, 1.861% (LIBOR + 
  
175 bps), 11/18/26 
1,457,779 
997,403  
Team Health Holdings, Inc., Initial Term Loan, 3.75% 
 
  
(LIBOR + 275 bps), 2/6/24 
930,790 
  Total Diversified & Conglomerate Service $ 9,863,549 
  Diversified Natural Resources & Precious Metals — 0.0%† 
 
997,500  
84 Lumber Co., Term B-1 Loan, 3.75% (LIBOR + 
 
  
300 bps), 11/13/26 
$ 998,996 
  Total Diversified Natural Resources & Precious Metals $ 998,996 
  Electronics — 0.3% 
 
694,750  
BY Crown Parent LLC, Initial B-1 Term Loan, 4.0% 
 
  
(LIBOR + 300 bps), 2/2/26 
$ 696,053 
1,340,173  
Dell International LLC (EMC Corp.), Refinancing 
 
  
Term B-2 Loan, 2.0% (LIBOR + 175 bps), 9/19/25 
1,340,652 
748,125  
Flexera Software LLC (fka Flexera Software, Inc.), First 
 
  
Lien Term B-1 Loan, 4.5% (LIBOR + 
 
  
375 bps), 3/3/28 
750,463 
400,000  
Rackspace Technology Global, Inc., First Lien 2021 
 
  
Term B Loan, 3.5% (LIBOR + 275 bps), 2/15/28 
397,350 
1,704,681  
Science Applications International Corp., Tranche B2 
 
  
Term Loan, 1.984% (LIBOR + 188 bps), 3/12/27 
1,707,451 
3,561,751  
Scientific Games International, Inc., Initial Term B-5 
 
  
Loan, 2.859% (LIBOR + 275 bps), 8/14/24 
3,497,639 
500,000  
Spectrum Brands, Inc., 2021 Term Loan, 2.5% (LIBOR + 
 
  
200 bps), 3/3/28 
499,479 
1,000,000  
Ultra Clean Holdings, Inc., Term Loan, 3.859% (LIBOR + 
 
  
375 bps), 8/27/25 
1,003,750 
1,989,664  
Verint Systems, Inc., Refinancing Term Loan, 2.115% 
 
  
(LIBOR + 200 bps), 6/28/24 
1,989,664 
1,166,806  
Western Digital Corp., US Term B-4 Loan, 1.865% 
 
  
(LIBOR + 175 bps), 4/29/23 
1,168,056 
  Total Electronics $ 13,050,557 
  Entertainment & Leisure — 0.1% 
 
1,488,750  
Carnival Corp., Initial Advance, 8.5% (LIBOR + 
 
  
750 bps), 6/30/25 
$ 1,540,856 
500,000  
Churchill Downs, Inc., 2021 Incremental Term B 
 
 
 
Loan, 2.12% (LIBOR + 200 bps), 3/17/28 
498,750 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 73

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Entertainment & Leisure — (continued) 
 
660,000(i)  
Enterprise Development Authority, Term 
 
 
 
Loan B, 2/18/28 
$ 662,888 
847,875  
Great Outdoors Group LLC, Term B-1 Loan, 5.0% 
 
 
 
(LIBOR + 425 bps), 3/6/28 
849,288 
1,250,000  
Resideo Funding, Inc., Initial Term Loan, 2.75% 
 
 
 
(LIBOR + 225 bps), 2/11/28 
1,250,000 
 
 Total Entertainment & Leisure $ 4,801,782 
 
 Environmental Services — 0.1% 
 
1,327,488  
GFL Environmental, Inc., 2020 Refinancing Term Loan, 
 
 
 
3.5% (LIBOR + 300 bps), 5/30/25 
$ 1,329,621 
750,000  
WIN Waste Innovations Holdings, Inc., Initial Term 
 
 
 
Loan, 0.0%, 3/24/28 
748,751 
 
 Total Environmental Services $ 2,078,372 
 
 Financial Services — 0.2% 
 
1,985,000  
Cardtronics USA, Inc., Initial Term Loan, 5.0% (LIBOR + 
 
 
 
400 bps), 6/29/27 
$ 1,989,962 
2,500,000  
Citadel Securities LP, 2021 Term Loan, 2.609% (LIBOR + 
 
 
 
250 bps), 2/2/28 
2,477,075 
487,517  
EFS Cogen Holdings I LLC, Term B Loan Advance, 
 
 
 
4.5% (LIBOR + 350 bps), 10/1/27 
486,516 
950,000(i)  
Hudson River Trading LLC, Term Loan, 3/20/28 
942,875 
1,802,036  
Trans Union LLC, 2019 Replacement Term B-5 Loan, 
 
 
 
1.859% (LIBOR + 175 bps), 11/16/26 
1,791,775 
 
 Total Financial Services $ 7,688,203 
 
 Forest Products — 0.1% 
 
1,000,000  
ProAmpac PG Borrower LLC, First Lien 2020-1 Term 
 
 
 
Loan, 5.0% (LIBOR + 400 bps), 11/3/25 
$ 1,000,500 
2,600,000(i)  
Schweitzer-Mauduit International, Inc., Term 
 
 
 
Loan B, 1/27/28 
2,596,750 
 
 Total Forest Products $ 3,597,250 
 
 Gaming & Hotels — 0.0%† 
 
850,000(i)  
Playtika Holding Corp., Term B-1 Loan, 3/13/28 
$ 846,206 
 
 Total Gaming & Hotels $ 846,206 
 
 Healthcare — 0.3% 
 
1,000,000  
ADMI Corp. (aka Aspen Dental) Amendment No. 4, 
 
 
 
Refinancing Term Loan, 3.75% (LIBOR + 
 
 
 
325 bps), 12/23/27 
$ 992,361 
1,061,053  
Alkermes, Inc., 2026 Term Loan, 3.0% (LIBOR + 
 
 
 
250 bps), 3/12/26 
1,061,053 
500,000  
CNT Holdings I Corp, First Lien Initial Term Loan, 4.5% 
 
 
 
(LIBOR + 375 bps), 11/8/27 
499,375 
2,509,946  
Grifols Worldwide Operations, Ltd., Dollar Tranche B 
 
 
 
Term Loan, 2.081% (LIBOR + 200 bps), 11/15/27 
2,485,132 
 
The accompanying notes are an integral part of these financial statements.
74 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Healthcare — (continued) 
 
1,150,000  
Horizon Therapeutics USA, Inc., Incremental Term 
 
  
B-2 Loan, 2.5% (LIBOR + 200 bps), 3/15/28 
$ 1,148,083 
2,358,343  
Horizon Therapeutics USA, Inc., Seventh Amendment 
 
  
Refinancing Term Loan, 2.125% (LIBOR + 
 
  
200 bps), 5/22/26 
2,357,360 
1,250,000(i)  
Phoenix Guarantor, Inc. (aka Brightspring), Term Loan, 
 
  
3/5/26 
1,244,140 
1,003,731  
Service Logic Acquisition, Inc., First Lien Closing Date 
 
  
Initial Term Loan, 4.75% (LIBOR + 
 
  
400 bps), 10/29/27 
1,004,986 
1,200,000  
Sotera Health Holdings LLC, Refinancing, First Lien 
 
  
Term Loan, 3.25% (LIBOR + 275 bps), 12/11/26 
1,198,500 
  Total Healthcare $ 11,990,990 
  Healthcare & Pharmaceuticals — 0.1% 
 
965,000  
Alphabet Holding Co., Inc. (aka Nature’s Bounty), 
 

 First Lien Initial Term Loan, 3.609% (LIBOR + 
  
350 bps), 9/26/24 
$ 959,745 
2,197,000  
Milano Acquisition Corp., First Lien Term B Loan, 4.75% 
 
  
(LIBOR + 400 bps), 10/1/27 
2,189,014 
1,494,266  
NMN Holdings III Corp., First Lien Closing Date Term 
 
  
Loan, 3.609% (LIBOR + 350 bps), 11/13/25 
1,479,323 
320,884  
NMN Holdings III Corp., First Lien Delayed Draw Term 
 
  
Loan, 3.609% (LIBOR + 350 bps), 11/13/25 
317,675 
214,835  
Prestige Brands, Inc., Term B-4 Loan, 2.109% (LIBOR + 
 
  
200 bps), 1/26/24 
214,969 
  Total Healthcare & Pharmaceuticals $ 5,160,726 

 Healthcare, Education & Childcare — 0.2% 
1,019,455  
ATI Holdings Acquisition, Inc., First Lien Initial Term 
 
  
Loan, 3.703% (LIBOR + 350 bps), 5/10/23 
$ 1,019,773 
2,062,500  
Bausch Health Cos., Inc. (fka Valeant Pharmaceuticals 
 

 International, Inc.), First Incremental Term 
  
Loan, 2.859% (LIBOR + 275 bps), 11/27/25 
2,054,172 
2,332,421  
Bausch Health Cos., Inc. (fka Valeant Pharmaceuticals 
 

 International, Inc.), Initial Term Loan, 3.109% 
  
(LIBOR + 300 bps), 6/2/25 
2,327,262 
1,470,000  
Vizient, Inc., Term B-6 Loan, 2.109% (LIBOR + 
 
  
200 bps), 5/6/26 
1,459,342 
  Total Healthcare, Education & Childcare $ 6,860,549 
  Home Furnishings — 0.0%† 
 
498,750  
Weber-Stephen Products LLC, Initial Term B Loan, 
 
  
4.0% (LIBOR + 325 bps), 10/30/27 
$ 499,218 
  Total Home Furnishings $ 499,218 
  Hotel, Gaming & Leisure — 0.2% 
 
1,197,069  
1011778 B.C. Unlimited Liability Co. (New Red Finance, 
 
  
Inc.) (aka Burger King/Tim Hortons), Term B-4 Loan, 
 
  
1.859% (LIBOR + 175 bps), 11/19/26 
$ 1,177,724 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 75 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Hotel, Gaming & Leisure — (continued) 
 
1,975,991  
Boyd Gaming Corp., Refinancing Term B Loan, 
 
 
 
2.331% (LIBOR + 225 bps), 9/15/23 
$ 1,974,420 
1,496,134  
Caesars Resort Collection LLC, Term B Loan, 
 
 
 
2.859% (LIBOR + 275 bps), 12/23/24 
1,474,627 
1,643,029  
Flutter Entertainment Plc, USD Term Loan, 
 
 
 
3.703% (LIBOR + 350 bps), 7/10/25 
1,648,163 
1,499,668  
Station Casinos LLC, Term B-1 Facility Loan, 2.5% 
 
 
 
(LIBOR + 225 bps), 2/8/27 
1,478,779 
 
 Total Hotel, Gaming & Leisure $ 7,753,713 
 
 Insurance — 0.2% 
 
982,500  
Alliant Holdings Intermediate LLC, 2019 New Term 
 
 
 
Loan, 3.359% (LIBOR + 325 bps), 5/9/25 
$ 972,061 
1,194,350  
Asurion LLC (fka Asurion Corp.) New B-8 Term Loan, 
 
 
 
3.359% (LIBOR + 325 bps), 12/23/26 
1,188,130 
4,224,360  
Asurion LLC (fka Asurion Corp.), New B-7 Term Loan, 
 
 
 
3.109% (LIBOR + 300 bps), 11/3/24 
4,213,140 
1,000,000  
Asurion LLC (fka Asurion Corp.), New B-9 Term Loan, 
 
 
 
3.359% (LIBOR + 325 bps), 7/31/27 
993,854 
382,498  
Confie Seguros Holding II Co., Term B Loan, 5.75% 
 
 
 
(LIBOR + 475 bps), 4/19/22 
378,025 
487,998  
Integro Parent, Inc., First Lien Initial Term Loan, 6.75% 
 
 
 
(LIBOR + 575 bps), 10/31/22 
480,068 
337,750  
USI, Inc. (fka Compass Investors, Inc.), 2017 New Term 
 
 
 
Loan, 3.203% (LIBOR + 300 bps), 5/16/24 
334,282 
 
 Total Insurance $ 8,559,560 
 
 Leasing — 0.1% 
 
498,750  
Avolon TLB Borrower 1 (US) LLC Term B-5 Loan, 
 
 
 
3.25% (LIBOR + 250 bps), 12/1/27 
$ 499,408 
1,144,959  
Avolon TLB Borrower 1 (US) LLC, Term B-3 Loan, 
 
 
 
2.5% (LIBOR + 175 bps), 1/15/25 
1,142,592 
1,371,636  
Avolon TLB Borrower 1 (US) LLC, Term B-4 Loan, 
 
 
 
2.25% (LIBOR + 150 bps), 2/12/27 
1,357,835 
1,051,669  
Fly Funding II S.a.r.l., Replacement Term Loan, 1.95% 
 
 
 
(LIBOR + 175 bps), 8/11/25 
1,034,579 
970,000  
IBC Capital I, Ltd. (aka Goodpack, Ltd.), First Lien 
 
 
 
Tranche B-1 Term Loan, 3.94% (LIBOR + 
 
 
 
375 bps), 9/11/23 
963,635 
 
 Total Leasing $ 4,998,049 
 
 Leisure & Entertainment — 0.1% 
 
498,750  
E.W. Scripps Co., Term Loan B3, 3.75% (LIBOR + 
 
 
 
300 bps), 1/7/28 
$ 497,859 
1,220,288  
Fitness International LLC, Term B Loan, 4.25% (LIBOR + 
 
 
 
325 bps), 4/18/25 
1,127,394 
500,000  
WMG Acquisition Corp., First Lien Term Loan, 2.234% 
 
 
 
(LIBOR + 213 bps), 1/20/28 
498,646 
 
 Total Leisure & Entertainment $ 2,123,899 
 
The accompanying notes are an integral part of these financial statements.
76 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Machinery — 0.1% 
 
95,197  
Clark Equipment Co. (aka Doosan Bobcat, Inc.), 
 

 Repriced 2019 Term Loan, 1.953% (LIBOR + 
  
175 bps), 5/18/24 
$ 94,557 
1,234,571  
CTC AcquiCo GmbH, Facility B2, 2.94% (LIBOR + 
 
  
275 bps), 3/7/25 
1,206,794 
139,717  
Gardner Denver, Inc., 2020 GDI Tranche B-2 Dollar 
 
  
Term Loan, 1.859% (LIBOR + 175 bps), 3/1/27 
138,319 
290,487  
Terex Corp., Incremental US Term Loan, 2.75% 
 
  
(LIBOR + 200 bps), 1/31/24 
290,306 
  Total Machinery $ 1,729,976 
  Media — 0.1% 
 
1,338,723  
CSC Holdings LLC (fka CSC Holdings, Inc. 
 
  
(Cablevision)), October 2018 Incremental Term Loan, 
 
  
2.356% (LIBOR + 225 bps), 1/15/26 
$ 1,322,945 
2,175,000  
Ziggo Financing Partnership, Term Loan I Facility, 
 
  
2.606% (LIBOR + 250 bps), 4/30/28 
2,155,819 
  Total Media $ 3,478,764 
  Metals & Mining — 0.1% 
 
860,223  
Atkore International, Inc., First Lien Initial Incremental 
 
  
Term Loan, 3.75% (LIBOR + 275 bps), 12/22/23 
$ 867,445 
850,000(i)  
Harsco Corp., Term Loan, 3/5/28 
845,042 
1,817,741  
Phoenix Guarantor, Inc. (aka Brightspring), First Lien 
 
  
Tranche B-1 Term Loan, 3.361% (LIBOR + 
 
  
325 bps), 3/5/26 
1,806,190 
  Total Metals & Mining $ 3,518,677 
  Oil & Gas — 0.1% 
 
3,552,089  
Centurion Pipeline Co. LLC (fka Lotus Midstream LLC), 
 
  
Initial Term Loan, 3.359% (LIBOR + 
 
  
325 bps), 9/29/25 
$ 3,543,209 
500,000  
Murphy Oil USA, Inc., Tranche B Term Loan, 2.25% 
 
  
(LIBOR + 175 bps), 1/31/28 
502,500 
992,153  
Traverse Midstream Partners LLC, Advance Term Loan, 
 
  
6.5% (LIBOR + 550 bps), 9/27/24 
987,605 
  Total Oil & Gas $ 5,033,314 
  Personal, Food & Miscellaneous Services — 0.0%† 
 
1,209,688  
Option Care Health, Inc., Term B Loan, 3.859% 
 
  
(LIBOR + 375 bps), 8/6/26 
$ 1,207,419 
  Total Personal, Food & Miscellaneous Services $ 1,207,419 
  Printing & Publishing — 0.0%† 
 
1,195,594  
Red Ventures LLC (New Imagitas, Inc.), First Lien 
 
  
Term B-2 Loan, 2.609% (Libor + 250 bps), 11/8/24 
$ 1,165,828 
  Total Printing & Publishing $ 1,165,828 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 77 

Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Professional & Business Services — 0.3% 
 
1,970,000  
Amentum Government Services Holdings LLC, First 
 
  
Lien Tranche 2 Term Loan, 5.5% (LIBOR + 
 
  
475 bps), 1/29/27 
$ 1,977,388 
1,000,000  
Ankura Consulting Group LLC, First Lien Closing 
 
  
Date Term Loan, 5.25% (LIBOR + 450 bps), 3/17/28 
998,750 
985,000  
Clear Channel Outdoor Holdings, Inc., Term B Loan, 
 
  
3.712% (LIBOR + 350 bps), 8/21/26 
948,854 
2,912,697  
Elanco Animal Health, Inc., Term Loan, 1.865% 
 
  
(LIBOR + 175 bps), 8/1/27 
2,878,109 
498,734  
Ensemble RCM LLC, Closing Date Term Loan, 3.962% 
 
  
(LIBOR + 375 bps), 8/3/26 
498,630 
332,496  
First Advantage Holdings LLC, First Lien Term B-1 
 
  
Loan, 3.109% (LIBOR + 300 bps), 1/31/27 
330,418 
1,228,125  
MYOB US Borrower LLC, First Lien Initial US Term Loan, 
 
  
4.109% (LIBOR + 400 bps), 5/6/26 
1,220,449 
1,568,995  
Nielsen Finance LLC, Dollar Term B-5 Loan, 4.75% 
 
  
(LIBOR + 375 bps), 6/4/25 
1,578,017 
1,000,000  
Petco Health & Wellness Co., Inc., First Lien Initial Term 
 
  
Loan, 4.0% (LIBOR + 325 bps), 3/3/28 
996,964 
416,667  
PPD, Inc., Initial Term Loan, 2.75% (LIBOR + 
 
  
225 bps), 1/13/28 
415,397 
746,250  
Pre-Paid Legal Services, Inc. (aka LegalShield), First 
 
  
Lien New Term Loan, 4.75% (LIBOR + 400 bps), 5/1/25 
750,448 
500,000(i)  
Verscend Holding Corp., Term B-1 Loan, 8/27/25 
500,000 
861,182  
Victory Capital Holdings, Inc., Tranche B-2 Term Loan, 
 
  
2.439% (LIBOR + 225 bps), 7/1/26 
854,185 
  Total Professional & Business Services $ 13,947,609 
  Retailing — 0.1% 
 
1,592,000  
Asplundh Tree Expert LLC, Amendment No. 1 Term 
 
  
Loan, 1.859% (LIBOR + 175 bps), 9/7/27 
$ 1,589,868 
1,500,000(i)  
Garrett LX I S.a.r.l., Term Loan B, 3/5/28 
1,490,625 
1,852,709  
KFC Holding Co. (aka Yum! Brands), 2021 Term B 
 
  
Loan, 1.856% (LIBOR + 175 bps), 3/15/28 
1,856,183 
500,000  
New Trojan Parent, Inc., First Lien Initial Term Loan, 
 
  
3.75% (LIBOR + 325 bps), 1/6/28 
498,230 
750,000  
PetSmart LLC, Initial Term Loan, 4.5% (LIBOR + 
 
  
375 bps), 2/11/28 
749,887 
  Total Retailing $ 6,184,793 
  Securities & Trusts — 0.0%† 
 
1,000,000(i)  
CCRR Parent, Inc., First Lien Initial Term Loan, 3/6/28 
$ 1,003,125 
288,771  
RPI Intermediate Finance Trust, Term B-1 Term Facility, 
 
  
1.859% (LIBOR + 175 bps), 2/11/27 
288,455 
  Total Securities & Trusts $ 1,291,580 
 
The accompanying notes are an integral part of these financial statements.
78 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
 Value
  Telecommunications — 0.4% 
 
2,474,752  
Ciena Corp., Refinancing Term Loan, 1.861% (LIBOR + 
 
  
175 bps/PRIME + 75 bps + 175 bps), 9/26/25 
$ 2,479,393 
2,415,258  
Go Daddy Operating Co. LLC (GD Finance Co., Inc.), 
 
  
Tranche B-2 Term Loan, 1.859% (LIBOR + 
 
  
175 bps), 2/15/24 
2,399,887 
1,240,625  
Go Daddy Operating Co. LLC (GD Finance Co., Inc.), 
 
  
Tranche B-4 Term Loan, 2.109% (LIBOR + 
 
  
200 bps), 8/10/27 
1,235,004 
3,990,234  
Level 3 Financing, Inc., Tranche B 2027 Term Loan, 
 
  
1.859% (LIBOR + 175 bps), 3/1/27 
3,944,630 
4,996,800  
Lumen Technologies, Inc. Term B Loan, 2.359% 
 
  
(LIBOR + 225 bps), 3/15/27 
4,945,662 
1,484,673  
Virgin Media Bristol LLC, N Facility, 2.606% (LIBOR + 
 
  
250 bps), 1/31/28 
1,473,453 
1,025,000(i)  
Virgin Media Bristol LLC, Term Q Loan, 1/31/29 
1,024,634 
1,050,000(i)  
Windstream Services II LLC, Initial Term Loan, 9/21/27 
1,052,625 
  Total Telecommunications $ 18,555,288 
  Transportation — 0.1% 
 
1,000,000  
Daseke Cos., Inc., 2021 Initial Term Loan, 4.75% 
 
  
(LIBOR + 400 bps), 3/9/28 
$ 1,002,500 
2,394,875  
Envision Healthcare Corp., Initial Term Loan, 3.859% 
 
  
(LIBOR + 375 bps), 10/10/25 
2,069,905 
64,381  
Syncreon Group BV, Second Out Term Loan, 7.0% 
 
  
(LIBOR + 600 bps), 4/1/25 
64,461 
  Total Transportation $ 3,136,866 
  Utilities — 0.2% 
 
1,030,159  
APLP Holdings, Ltd. Partnership, Term Loan, 3.5% 
 
  
(LIBOR + 250 bps), 4/14/25 
$ 1,029,301 
749,813  
Calpine Construction Finance Co., LP, Term B Loan, 
 
  
2.109% (LIBOR + 200 bps), 1/15/25 
741,190 
492,500  
Calpine Corp., Term Loan, 2.109% (LIBOR + 
 
  
200 bps), 8/12/26 
487,917 
1,923,303  
Compass Power Generation, LLC, Tranche B-1 Term 
 
  
Loan, 4.5% (LIBOR + 350 bps), 12/20/24 
1,914,286 
2,471,819  
Eastern Power LLC (Eastern Covert Midco LLC) (aka 
 

 TPF II LC LLC), Term Loan, 4.75% (LIBOR + 
  
375 bps), 10/2/25 
2,340,723 
562,634  
Vistra Operations Co. LLC (fka Tex Operations Co. LLC), 
 

 2018 Incremental Term Loan, 1.858% (LIBOR + 
  
175 bps), 12/31/25 
559,334 
  Total Utilities $ 7,072,751 
 
 TOTAL SENIOR SECURED FLOATING RATE LOAN INTERESTS 
 
 
 
(Cost $225,834,273) 
$ 225,383,675 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 79
Schedule of Investments | 3/31/21 (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 U.S. GOVERNMENT AND AGENCY 
 

 OBLIGATIONS — 9.4% of Net Assets
 
5,000,000  Fannie Mae, 1.5%, 4/1/36 (TBA) $ 5,021,094 
5,000,000  Fannie Mae, 1.5%, 5/1/36 (TBA) 5,013,177 
30,000,000  Fannie Mae, 2.0%, 4/1/36 (TBA) 30,779,297 
45,000,000  Fannie Mae, 2.0%, 4/1/51 (TBA) 44,867,285 
25,500,000  Fannie Mae, 2.0%, 5/1/51 (TBA) 25,377,978 
4,928(a)  Fannie Mae, 2.091% (2 Month USD LIBOR + 
 
 
 167 bps), 1/1/48 5,003 
6,420(a)  Fannie Mae, 2.283% (1 Year CMT Index + 
 
 
 210 bps), 9/1/32 6,562 
5,954(a)  Fannie Mae, 2.295% (1 Year CMT Index + 
 
 
 217 bps), 2/1/34 5,896 
83,000,000  Fannie Mae, 2.5%, 5/1/51 (TBA) 84,933,965 
50(a)  Fannie Mae, 2.527% (1 Year CMT Index + 
 
 
 211 bps), 11/1/23 50 
6,643(a)  Fannie Mae, 3.298% (1 Year CMT Index + 
 
 
 219 bps), 10/1/32 6,616 
1,520(a)  Federal Home Loan Mortgage Corp., 2.375% (2 Month 
 
 
 USD LIBOR + 200 bps), 11/1/33 1,524 
362(a)  Federal Home Loan Mortgage Corp., 2.594% (1 Year 
 
 
 CMT Index + 229 bps), 10/1/23 360 
729(a)  Federal Home Loan Mortgage Corp., 4.371% (5 Year 
 
 
 CMT Index + 212 bps), 6/1/35 733 
648(a)  Government National Mortgage Association II, 3.0% 
 
 
 (1 Year CMT Index + 150 bps), 1/20/22 651 
110,000,000(j)  U.S. Treasury Bills, 4/1/21 110,000,000 
90,000,000(j)  U.S. Treasury Bills, 4/27/21 89,998,862 
25,000,000  
U.S. Treasury Note, 2.875%, 10/15/21 
25,378,906 
 
 TOTAL U.S. GOVERNMENT AND AGENCY OBLIGATIONS 
 
 
 
(Cost $422,627,183) 
$ 421,397,959 
 
 TEMPORARY CASH INVESTMENTS — 4.7% 
 
 
 of Net Assets 
 
 
 COMMERCIAL PAPERS — 3.7% 
 
9,200,000  Canadian Natural Resources, Ltd., 0.31%, 4/14/21 $ 9,199,431 
18,400,000  CenterPoint Energy, 0.12%, 4/1/21 18,399,939 
23,000,000  Conagra Foods, 0.25%, 4/1/21 22,999,678 
18,400,000  Energy Transfer, 0.4%, 4/1/21 18,399,811 
18,400,000  Eni Finance USA, Inc., 0.1%, 4/1/21 18,399,947 
18,400,000  Federation des Caisses Desjardins du Quebec, 
 
 
 0.07%, 4/1/21 18,399,972 
13,810,000  PPL Electric Utilities, 0.14%, 4/8/21 13,809,536 
18,415,000  PPL Electric Utilities, 0.16%, 4/9/21 18,414,297 
18,400,000  Prudential Funding LLC, 0.05%, 4/1/21 18,399,984 
9,200,000  Smithfield Foods, 0.23%, 4/1/21 9,199,905 
 
 
 
$ 165,622,500 
 
The accompanying notes are an integral part of these financial statements.
80 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  CERTIFICATE OF DEPOSIT — 0.2% 
 
6,100,000(a)  Lloyds Bank Corporate Markets Plc, 0.773% (3 Month 
 
  
USD LIBOR + 55 bps), 7/19/21 
$ 6,108,981 
  REPURCHASE AGREEMENTS — 0.8% 
 
9,020,000  $9,020,000 Merrill Lynch, Pierce, Fenner & Smith, Inc., 
 
  0.01%, dated 3/31/21 plus accrued interest on 4/01/21 
 
  collateralized by $9,200,400 Government National 
 
  Mortgage Association, 2.5%-3.5%, 10/20/47-3/20/51 $ 9,020,000 
9,020,000  $9,020,000 RBC Capital Markets LLC, 0.01%, 
 

 dated 3/31/21 plus accrued interest on 4/1/21
 
  collateralized by the following: 
 
  $62,135 Freddie Mac Giant, 3.5%, 2/1/47-1/1/48 
 
  $6,833,519 Federal National Mortgage 
 
  Association, 3.0%, 11/1/49 
 

 $2,304,748 Government National Mortgage
 
  Association, 2.5%, 9/20/50. 9,020,000 
9,020,000  $9,020,000 ScotiaBank, 0.01%, dated 3/31/21 
 

 plus accrued interest on 4/1/21 collateralized 
  by the following: 
 

 $1,361,521 Freddie Mac Giant, 3.5%, 2/1/44
 
  $7,838,955 U.S. Treasury Bill, 0.0%, 6/3/21. 9,020,000 
4,510,000  $4,510,000 TD Securities USA LLC, 0.01%, dated 
 
  3/31/21 plus accrued interest on 4/1/21 collateralized 
 

 by $4,600,219 U.S. Treasury Notes, 0.1-2.6%,
 
  6/15/21-10/31/27. 4,510,000 
4,510,000  $4,510,000 TD Securities USA LLC, 0.01%, dated 
 
  3/31/21 plus accrued interest on 4/1/21 collateralized 
 

  by $4,600,234 U.S. Treasury Notes, 0.1-2.6%, 
 
 7/15/21-8/31/27. 4,510,000 
  
 
$ 36,080,000 
 
 TOTAL TEMPORARY CASH INVESTMENTS 
 
 
 
(Cost $207,802,034) 
$ 207,811,481 
 
 TOTAL INVESTMENTS IN UNAFFILIATED ISSUERS — 103.5% 
 
 
 
(Cost $4,623,232,325) 
$4,618,051,452 
 
 OTHER ASSETS AND LIABILITIES — (3.5)% $ (155,876,967) 
 
 NET ASSETS — 100.0% $4,462,174,485 
 
bps 
Basis Points. 
CMT 
Constant Maturity Treasury Index. 
FREMF 
Freddie Mac Multifamily Fixed-Rate Mortgage Loans. 
LIBOR 
London Interbank Offered Rate. 
PRIME 
U.S. Federal Funds Rate. 
REIT 
Real Estate Investment Trust. 
REMICS 
Real Estate Mortgage Investment Conduits. 
SOFRRATE 
Secured Overnight Financing Rate. 
Strips 
Separate trading of Registered interest and principal of securities. 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 81

Schedule of Investments | 3/31/21 (continued)
(144A) 
Security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers in a transaction exempt from registration. At March 31, 2021, the value of these securities amounted to $2,552,593,677, or 57.2% of net assets.
(TBA) 
“To Be Announced” Securities. 
† 
Amount rounds to less than 0.1%. 
Senior secured floating rate loan interests in which the Fund invests generally pay interest at rates that are periodically redetermined by reference to a base lending rate plus a premium. These base lending rates are generally (i) the lending rate offered by one or more major European banks, such as LIBOR, (ii) the prime rate offered by one or more major United States banks, (iii) the rate of a certificate of deposit or (iv) other base lending rates used by commercial lenders. The interest rate shown is the rate accruing at March 31, 2021.
Security that used significant unobservable inputs to determine its value. 
(a) 
Floating rate note. Coupon rate, reference index and spread shown at March 31, 2021. 
(b) 
The interest rate is subject to change periodically. The interest rate and/or reference 
 
index and spread shown at March 31, 2021. 
(c) 
Debt obligation initially issued at one coupon which converts to a higher coupon at a 
 
specific date. The rate shown is the rate at March 31, 2021. 
(d) 
Security is perpetual in nature and has no stated maturity date. 
(e) 
Non-income producing security. 
(f) 
Issued as participation notes. 
(g) 
Issued as preference shares. 
(h) 
Consists of Revenue Bonds unless otherwise indicated. 
(i) 
This term loan will settle after March 31, 2021, at which time the interest rate will be determined.
(j) 
Security issued with a zero coupon. Income is recognized through accretion of discount. 
Securities are restricted as to resale. 
 
    
Restricted Securities Acquisition date Cost Value 
Ailsa Re 2019 
6/4/2019 $2,750,000 $ 2,915,473 
Akibare Re 
3/22/2018 500,000 502,250 
Akibare Re 
3/22/2018 250,000 251,000 
Alamo Re 
3/24/2021 1,002,700 1,001,200 
Alamo Re II 
5/29/2020 2,500,000 2,613,750 
Alturas Re 2019-1 
12/20/2018 2,000 9,146 
Alturas Re 2019-2 
12/19/2018 36,448 96,802 
Aozora Re 
3/20/2017 1,500,000 1,500,000 
Bantry Re 2016 
2/6/2019 201,500 201,500 
Bantry Re 2017 
2/6/2019 116,928 116,882 
Bantry Re 2018 
2/6/2019 22,757 22,800 
Bantry Re 2019 
2/1/2019 — 135,855 
Berwick Re 2017-1 
1/5/2017 41,453 41,375 
Berwick Re 2018-1 
1/10/2018 844,301 491,956 
Berwick Re 2019-1 
12/31/2018 437,104 437,135 
Blue Lotus Re 2018 
12/20/2017 — 46,050 
Bonanza Re 
2/13/2020 1,500,000 1,513,500 
Bonanza Re 
12/15/2020 2,000,000 2,017,600 
Bowline Re 
6/17/2020 244,973 253,025 
Bowline Re 
3/12/2019 250,000 256,275 
 
The accompanying notes are an integral part of these financial statements.
82 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Restricted Securities Acquisition date Cost Value 
Caelus Re V 
5/4/2018 $ 750,000 $ 375,000 
Caelus Re V 
4/27/2017 125,000 50,000 
Caelus Re V 
5/4/2018 500,000 350,000 
Caelus Re VI 
2/20/2020 750,000 769,650 
Carnoustie Re 2017 
1/3/2017 475,515 263,600 
Carnoustie Re 2019 
12/31/2018 — 2,090 
Castle Stuart Re 2018 
12/20/2017 349,024 46,874 
Cypress Re 2017 
1/24/2017 3,361 100 
Denning Re 
11/9/2020 2,937,354 3,003,004 
Dingle Re 2019 
3/4/2019 — 10,263 
Dingle Re 2020 
2/13/2020 232,875 258,623 
Easton Re Pte 
12/15/2020 4,500,000 4,529,250 
Eden Re II 
12/15/2017 4,482 61,127 
Eden Re II 
1/23/2018 2,621 89,565 
Eden Re II 
1/22/2019 4,198 207,090 
Eden Re II 
12/14/2018 1,152 21,633 
First Coast Re 2017-1 Ltd. 
3/26/2021 1,757,350 1,755,075 
First Coast Re II Pte 
6/15/2020 684,256 708,120 
FloodSmart Re 
4/10/2019 500,000 499,950 
Formby Re 2018 
7/9/2018 220,653 278,387 
Fortius Re II 
7/13/2017 500,000 502,000 
Four Lakes Re 
11/5/2020 1,750,000 1,739,675 
Gleneagles Re 2016 
1/14/2016 — 40,560 
Gullane Re 2018 
3/26/2018 218,739 361,093 
Harambee Re 2018 
12/19/2017 101,722 7,200 
Harambee Re 2019 
12/20/2018 — 33,600 
Herbie Re 
10/19/2020 500,000 531,300 
Hypatia, Ltd. 
7/10/2020 2,500,000 2,648,750 
Hypatia, Ltd. 
7/10/2020 1,000,000 1,064,000 
Integrity Re 
4/19/2018 2,494,743 2,498,000 
International Bank for Reconstruction & 
 
 
 
Development 
2/28/2020 500,000 505,500 
International Bank for Reconstruction & 
 
 
 
Development 
2/28/2020 500,000 505,500 
Kendall Re 
6/12/2020 498,181 499,250 
Kilimanjaro II Re 
6/12/2020 342,038 350,525 
Kilimanjaro II Re 
4/6/2017 1,700,000 1,716,150 
Kilimanjaro Re 
6/12/2020 246,230 251,575 
Kizuna Re II 
6/5/2020 247,429 250,800 
Kizuna Re II 
3/16/2018 747,273 751,650 
Limestone Re 
6/20/2018 164,830 307,784 
Limestone Re 2016-1 
12/15/2016 1,980 1,999 
Limestone Re 2016-1 
12/15/2016 3,300 3,332 
Limestone Re 2018 
6/20/2018 2,000 
Lion Rock Re 2019 
12/17/2018 — 20,250 
Long Point Re III 
5/17/2018 1,250,000 1,253,375 
Lorenz Re 2018 
6/26/2018 907,562 42,800 
Lorenz Re 2019 
6/26/2019 875,139 128,994 
Matterhorn Re 
6/5/2020 395,420 390,360 
Matterhorn Re 
11/24/2020 3,000,000 3,012,000 
Matterhorn Re 
11/24/2020 1,500,000 1,504,350 
Matterhorn Re 
1/29/2020 1,496,626 1,513,200 
Matterhorn Re 
4/30/2020 250,000 255,325 
Matterhorn Re 
6/25/2020 2,330,439 2,330,750 
Matterhorn Re 
6/25/2020 2,250,000 2,320,875 
Matterhorn Re 2020-1 
12/20/2019 2,000,000 2,012,800 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 83
 
Schedule of Investments | 3/31/21 (continued)
    
Restricted Securities Acquisition date Cost Value 
Merion Re 2018-2 
12/28/2017 $ 123,456 $ 496,500 
Nakama Re 
9/21/2016 698,472 700,770 
NCM Re 2019 
12/27/2018 5,323 92,536 
Northshore Re II 
12/2/2020 1,500,000 1,536,000 
Oakmont Re 2017 
5/10/2017 — 14,700 
Pangaea Re 2016-2 
5/31/2016 — 2,675 
Pangaea Re 2018-1 
12/26/2017 285,564 42,109 
Pangaea Re 2018-3 
5/31/2018 963,444 82,974 
Pangaea Re 2019-1 
1/9/2019 29,396 58,345 
Pangaea Re 2019-3 
7/25/2019 88,238 105,800 
Port Royal Re 2019 
5/20/2019 3,682,625 4,179,067 
Portrush Re 2017 
6/12/2017 613,588 510,480 
Residential Reinsurance 2017 
4/19/2017 2,099,997 2,091,180 
Residential Reinsurance 2017 
11/3/2017 2,900,000 2,906,380 
Residential Reinsurance 2018 
4/30/2018 1,250,000 1,231,875 
Residential Reinsurance 2019 
5/8/2019 500,000 493,350 
Residential Reinsurance 2020 
10/30/2020 1,500,000 1,520,250 
Residential Reinsurance 2020 
5/27/2020 500,000 502,700 
Resilience Re 
2/8/2017 1,209 250 
Resilience Re 
4/13/2017 6,535 200 
Sanders Re 
6/12/2020 244,371 249,275 
Sanders Re II, Ltd. 
5/20/2020 250,000 255,000 
Sector Re V 
1/1/2020 160,000 379,947 
Sector Re V 
12/4/2018 912,201 562,702 
Sector Re V, Series 9, Class A 
4/23/2019 800,000 450,657 
Sector Re V, Series 9, Class G 
5/1/2019 1,861 31,036 
Spectrum Capital, Ltd. 
6/12/2020 995,628 1,004,600 
St. Andrews Re 2017-1 
1/5/2017 84,685 84,750 
St. Andrews Re 2017-4 
3/31/2017 — 171,018 
Sussex Capital UK Pcc Ltd. 
12/7/2020 1,000,000 1,019,000 
Tailwind Re 
12/20/2017 3,349,509 3,384,170 
Thopas Re 2018 
12/12/2017 101,823 4,725 
Thopas Re 2019 
12/21/2018 113,673 125,400 
Torrey Pines Re Pte Ltd. 
3/12/2021 1,000,000 999,900 
Ursa Re 
11/20/2019 745,543 759,450 
Ursa Re 
9/7/2018 996,267 1,001,100 
Ursa Re II Ltd. 
10/8/2020 4,000,000 4,088,400 
Versutus Re 2018 
1/31/2018 12,692 6,600 
Versutus Re 2019-A 
1/28/2019 — 32,831 
Versutus Re 2019-B 
12/24/2018 — 26,689 
Viribus Re 2018 
12/22/2017 61,163 — 
Viribus Re 2019 
12/27/2018 — 103,250 
Vitality Re X 
2/3/2020 3,497,452 3,482,500 
Vitality Re X 
1/31/2020 1,748,996 1,715,000 
Vitality Re X 
1/23/2020 3,000,000 2,925,000 
Vitality Re XI 
1/23/2020 1,243,946 1,218,125 
Woburn Re 2018 
3/20/2018 610,386 126,599 
Woburn Re 2019 
1/30/2019 211,290 239,345 
Total Restricted Securities 
 
 
$98,073,507 
% of Net assets 
 
 
2.2% 
 
The accompanying notes are an integral part of these financial statements.
84 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

      
FUTURES CONTRACTS 
 
 
 
 
FIXED INCOME INDEX FUTURES CONTRACTS 
 
 
 
Number of 
 
 
 
 
 
Contracts 
 
Expiration Notional Market Unrealized 
Short Description Date Amount Value Appreciation 
375 
U.S. 5 Year 
6/30/21 
$ (46,859,805) $ (46,274,414) $ 585,391 
 
Note (CBT) 
 
   
670 
U.S. 10 Year 
6/21/21 
(89,581,250) (87,728,125) 1,853,125 
 
Note (CBT) 
 
   
250 
U.S. Long 
6/21/21 
(40,396,484) (38,648,438) 1,748,046 
 
Bond (CBT) 
 
   
TOTAL FUTURES CONTRACTS $(176,837,539) $(172,650,977) $ 4,186,562 
 
Principal amounts are denominated in U.S. dollars (“USD”) unless otherwise noted.
Purchases and sales of securities (excluding temporary cash investments) for the year ended March 31, 2021 were as follows:
 
Purchases Sales 
Long-Term U.S. Government Securities 
$ 85,189,380 
$ 598,514,465 
Other Long-Term Securities 
$2,003,390,473 
$2,505,088,083 
 
The Fund is permitted to engage in purchase and sale transactions (“cross trades”) with certain funds and accounts for which Amundi Asset Management US, Inc. (the “Adviser”) serves as the Fund’s investment adviser, as set forth in Rule 17a-7 under the Investment Company Act of 1940, pursuant to procedures adopted by the Board of Trustees. Under these procedures, cross trades are effected at current market prices. During the year ended March 31, 2021, the Fund engaged in purchases of $10,988,054 and sales of $6,209,645 pursuant to these procedures, which resulted in a net realized gain/(loss) of $7,709.
At March 31, 2021, the net unrealized depreciation on investments based on cost for federal tax purposes of $4,640,881,493 was as follows:
Aggregate gross unrealized appreciation for all investments in which 
 
there is an excess of value over tax cost $ 23,938,360 
Aggregate gross unrealized depreciation for all investments in which 
 
there is an excess of tax cost over value (42,581,839) 
Net unrealized depreciation 
$(18,643,479) 
Various inputs are used in determining the value of the Fund’s investments. These inputs are summarized in the three broad levels below.
Level 1 -
unadjusted quoted prices in active markets for identical securities.
Level 2 -
other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risks, etc.). See Notes to Financial Statements — Note 1A.
Level 3 -
significant unobservable inputs (including the Fund’s own assumptions in determining fair value of investments). See Notes to Financial Statements — Note 1A.

The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 85
Schedule of Investments | 3/31/21 (continued)
The following is a summary of the inputs used as of March 31, 2021, in valuing the Fund’s investments:
     
 
 Level 1
Level 2 Level 3 Total 
Asset Backed Securities 
$ — $ 1,142,608,012 $17,200,000 $1,159,808,012 
Collateralized Mortgage 
 
 
 
 
Obligations — 699,054,752 — 699,054,752 
Commercial Mortgage-Backed 
 
 
 
 
Securities — 491,020,560 — 491,020,560 
Corporate Bonds 
— 1,315,471,908 — 1,315,471,908 
Insurance-Linked Securities 
 
 
 
 
Collateralized Reinsurance 
 
 
 
 
Multiperil - Massachusetts — — 3,003,004 3,003,004 
Multiperil - U.S. — — 4,447,953 4,447,953 
Multiperil - U.S. Regional — — 2,915,473 2,915,473 
Multiperil - Worldwide — — 313,665 313,665 
Windstorm - Florida — — 788,867 788,867 
Windstorm - U.S. Regional — — 14,700 14,700 
Reinsurance Sidecars 
 
 
 
 
Multiperil - U.S. — — 353,364 353,364 
Multiperil - Worldwide — — 5,799,101 5,799,101 
All Other Insurance-Linked 
 
 
 
 
Securities — 80,437,380 — 80,437,380 
Municipal Bond 
— 29,598 — 29,598 
Senior Secured Floating Rate 
 
 
 
 
Loan Interests — 225,383,675 — 225,383,675 
U.S. Government and Agency 
 
 
 
 
Obligations — 421,397,959 — 421,397,959 
Commercial Papers 
— 165,622,500 — 165,622,500 
Certificate of Deposit 
— 6,108,981 — 6,108,981 
Repurchase Agreements 
— 36,080,000 — 36,080,000 
Total Investments in Securities $ — $ 4,583,215,325 $34,836,127 $4,618,051,452 
Other Financial Instruments 
 
 
 
 
Net unrealized appreciation 
 
 
 
 
on futures contracts $4,186,562 $ — $ — $ 4,186,562 
Total Other 
 
 
 
 
Financial Instruments $4,186,562 $ — $ — $ 4,186,562 
 
The accompanying notes are an integral part of these financial statements.
86 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 
The following is a reconciliation of assets valued using significant unobservable inputs (Level 3):
    
 
Asset Insurance- 
 
 
Backed Linked 
 
 
Securities Securities Total 
Balance as of 3/31/20 
$ — $ 61,676,226 $ 61,676,226 
Realized gain (loss)(1) 
(1,617,540) (1,617,538) 
Change in unrealized depreciation(2) 
(156,667) (584,173) (740,840) 
Accrued discounts/premiums 
(22,676,954) — (22,676,954) 
Purchases 
10,000,000 2,937,354 12,937,354 
Sales 
— (44,294,990) (44,294,990) 
Transfers in to Level 3* 
30,033,619 — 30,033,619 
Transfers out of Level 3* 
— (480,750) (480,750) 
Balance as of 3/31/21 $ 17,200,000 $ 17,636,127 $ 34,836,127 
(1)     
Realized gain (loss) on these securities is included in the realized gain (loss) from investments on the Statement of Operations.
(2)     
Unrealized appreciation (depreciation) on these securities is included in the change in unrealized appreciation (depreciation) from investments on the Statement of Operations.
*     
Transfers are calculated on the beginning of period value. For the year ended March 31, 2021 an investment having a value of $480,750 was transferred out of Level 3 to Level 2, as there were significant observable inputs available to determine its value. Securities valued at $30,033,619 were transferred from Level 2 to Level 3, due to valuing the security using significant unobservable inputs. There were no other transfers in or out of Level 3.
  
Net change in unrealized appreciation (depreciation) of Level 3 investments still 
 
held and considered Level 3 at March 31, 2021: 
$(825,703) 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 87
 

Statement of Assets and Liabilities | 3/31/21
ASSETS: 
 
Investments in unaffiliated issuers, at value (cost $4,623,232,325) $4,618,051,452 
Cash 74,824,289 
Due from broker for futures 3,295,231 
Variation margin for futures contracts 338,398 
Net unrealized appreciation on futures contracts 4,186,562 
Unrealized appreciation on unfunded loan commitments 751 
Receivables — 
 
Investment securities sold 208,517,083 
Fund shares sold 25,181,455 
Interest 6,310,023 
   Other assets 
46,592 
Total assets $4,940,751,836 
LIABILITIES: 
 
Payables — 
 
Investment securities purchased $ 466,087,033 
Fund shares repurchased 11,053,159 
Distributions 382,886 
Trustees’ fees 4,960 
Due to affiliates 258,412 
   Accrued expenses 
790,901 
Total liabilities $ 478,577,351 
NET ASSETS: 
 
Paid-in capital $4,717,397,777 
   Distributable earnings (loss) 
(255,223,292) 
Net assets $4,462,174,485 
NET ASSET VALUE PER SHARE: 
 
No par value (unlimited number of shares authorized) 
 
Class A (based on $1,561,042,342/160,774,829 shares) $ 9.71 
Class C (based on $213,396,140/21,967,578 shares) $ 9.71 
Class C2 (based on $19,431,927/1,999,570 shares) $ 9.72 
Class K (based on $332,949,239/34,187,517 shares) $ 9.74 
   Class Y (based on $2,335,354,837/240,096,736 shares) 
$ 9.73 
 
The accompanying notes are an integral part of these financial statements.
88 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

   
Statement of Operations 
 
 
FOR THE YEAR ENDED 3/31/21 
 
 
 
INVESTMENT INCOME: 
 
 
Interest from unaffiliated issuers $ 85,778,040 
 
Dividends from unaffiliated issuers 3,593,498 
 
Total investment income 
 
$ 89,371,538 
EXPENSES: 
 
 
Management fees $ 14,609,879 
 
Administrative expense 1,146,370 
 
Transfer agent fees 
 
 
Class A 469,666 
 
Class C 97,221 
 
Class C2 5,727 
 
Class K 663 
 
Class Y 1,878,958 
 
Distribution fees 
 
 
Class A 3,167,700 
 
Class C 1,293,329 
 
Class C2 106,102 
 
Shareowner communications expense 140,345 
 
Custodian fees 172,008 
 
Registration fees 364,169 
 
Professional fees 297,607 
 
Printing expense 84,603 
 
Pricing fees 234,578 
 
Trustees’ fees 264,271 
 
Insurance expense 8,279 
 
Miscellaneous 265,869 
 
Total expenses 
 
$ 24,607,344 
Net investment income 
 
$ 64,764,194 
REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS: 
 
Net realized gain (loss) on: 
 
 
Investments in unaffiliated issuers $(33,580,400) 
 
Futures contracts 3,633,631 $ (29,946,769) 
Change in net unrealized appreciation (depreciation) on: 
 
 
Investments in unaffiliated issuers $266,189,674 
 
Futures contracts 4,186,562 
 
Unfunded loan commitments 123,080 $270,499,316 
Net realized and unrealized gain (loss) on investments 
 
$240,552,547 
Net increase in net assets resulting from operations 
 
$305,316,741 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 89
 

Statements of Changes in Net Assets
 
Year Year 
 
Ended Ended 
 
3/31/21 3/31/20 
FROM OPERATIONS: 
 
 
Net investment income (loss) 
$ 64,764,194 $ 161,673,331 
Net realized gain (loss) on investments 
(29,946,769) 167,329,917 
Change in net unrealized appreciation (depreciation) 
 
 
on investments 270,499,316 (254,161,235) 
Net increase (decrease) in net assets resulting 
 
 
from operations $ 305,316,741 $ (259,817,821) 
DISTRIBUTIONS TO SHAREOWNERS: 
 
 
Class A ($0.14 and $0.27 per share, respectively) $ (23,468,860) $ (48,393,422) 
Class C ($0.11 and $0.24 per share, respectively) (3,101,971) (9,350,830) 
Class C2 ($0.11 and $0.24 per share, respectively) (249,644) (292,948) 
Class K ($0.16 and $0.30 per share, respectively) (4,784,655) (10,737,706) 
Class Y ($0.16 and $0.29 per share, respectively) (41,860,447) (105,798,339) 
Total distributions to shareowners $ (73,465,577) $ (174,573,245) 
FROM FUND SHARE TRANSACTIONS: 
 
 
Net proceeds from sales of shares 
$ 2,407,423,803 $ 5,510,392,928 
Reinvestment of distributions 
66,896,801 158,619,800 
Cost of shares repurchased 
(3,448,386,566) (5,915,746,371) 
Net decrease in net assets resulting from 
 
 
Fund share transactions $ (974,065,962) $ (246,733,643) 
Net decrease in net assets $ (742,214,798) $ (681,124,709) 
NET ASSETS: 
 
 
Beginning of year 
$ 5,204,389,283 $ 5,885,513,992 
End of year 
$ 4,462,174,485 $ 5,204,389,283 
 
The accompanying notes are an integral part of these financial statements.
90 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

     
 
Year Ended Year Ended Year Ended Year Ended 
 
3/31/21 3/31/21 3/31/20 3/31/20 
 
Shares Amount Shares Amount 
Class A 
 
 
 
 
Shares sold 
92,373,581 $ 886,769,664 207,659,616 $ 2,059,762,141 
Reinvestment of 
 
 
 
 
distributions 2,382,681 22,795,230 4,724,639 46,618,899 
Less shares repurchased 
(109,824,891) (1,052,773,657) (188,391,509) (1,839,757,207) 
Net increase 
 
 
 
 
(decrease) (15,068,629) $ (143,208,763) 23,992,746 $ 266,623,833 
Class C 
 
 
 
 
Shares sold 
2,845,019 $ 27,288,975 11,059,054 $ 109,569,322 
Reinvestment of 
 
 
 
 
distributions 322,731 3,084,820 945,924 9,341,514 
Less shares repurchased 
(13,602,866) (130,287,105) (22,585,668) (221,897,172) 
Net decrease (10,435,116) $ (99,913,310) (10,580,690) $ (102,986,336) 
Class C2 
 
 
 
 
Shares sold 
555,563 $ 5,322,027 1,697,084 $ 16,812,541 
Reinvestment of 
 
 
 
 
distributions 2,471 23,635 7,983 78,821 
Less shares repurchased 
(822,826) (7,923,067) (309,176) (2,999,390) 
Net increase 
 
 
 
 
(decrease) (264,792) $ (2,577,405) 1,395,891 $ 13,891,972 
Class K 
 
 
 
 
Shares sold 
11,441,104 $ 110,280,243 16,044,359 $ 159,364,345 
Reinvestment of 
 
 
 
 
distributions 494,679 4,751,958 1,078,075 10,665,224 
Less shares repurchased 
(6,222,864) (59,630,837) (16,312,518) (159,929,239) 
Net increase 5,712,919 $ 55,401,364 809,916 $ 10,100,330 
Class Y 
 
 
 
 
Shares sold 
143,661,948 $ 1,377,762,894 319,898,241 $ 3,164,884,579 
Reinvestment of 
 
 
 
 
distributions 3,783,028 36,241,158 9,300,699 91,915,342 
Less shares repurchased 
(229,854,987) (2,197,771,900) (376,494,340) (3,691,163,363) 
Net decrease (82,410,011) $ (783,767,848) (47,295,400) $ (434,363,442) 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 91

Financial Highlights
      
 
Year Year Year Year
Year 
 
Ended Ended Ended Ended Ended 
 
3/31/21 3/31/20 3/31/19 3/31/18 3/31/17* 
Class A      
Net asset value, beginning of period 
$ 9.26 $ 9.92 $ 9.95 $ 9.99 $ 9.92 
Increase (decrease) from investment operations: 
     
Net investment income (loss)(a) $ 0.12 $ 0.25 $ 0.26 $ 0.18 $ 0.16 
Net realized and unrealized gain (loss) on investments  0.47 (0.64)
 (0.03)

0.08 
Net increase (decrease) from investment operations $ 0.59 $ (0.39) $ 0.23 $ 0.15 $ 0.24 
Distributions to shareowners: 
     
Net investment income $ (0.14) $ (0.27) $ (0.26) $ (0.19) $ (0.17) 
Total distributions $ (0.14) $ (0.27) $ (0.26) $ (0.19) $ (0.17) 
Net increase (decrease) in net asset value $ 0.45 $ (0.66) $ (0.03) $ (0.04) $ 0.07 
Net asset value, end of period 
$ 9.71 $ 9.26 $ 9.92 $ 9.95 $ 9.99 
Total return(b) 
 6.42%
 (4.02)%
 2.32%
1.51%
2.43% 
Ratio of net expenses to average net assets 
 0.60%
 0.58%
 0.59%
0.60%
0.61% 
Ratio of net investment income (loss) to average net assets 
 1.29%
 2.52%
 2.58%
1.81%
1.59% 
Portfolio turnover rate 
 51%
 100%
 61%
54%
69% 
Net assets, end of period (in thousands) 
$1,561,042 $1,628,082 $1,506,433 $1,209,820 $759,455 
*     
The Fund was audited by an independent registered public accounting firm other than Ernst & Young LLP.
(a)     
The per share data presented above is based on the average shares outstanding for the period presented.
(b)     
Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges were taken into account.
The accompanying notes are an integral part of these financial statements.
92 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

      
 
Year Year Year Year
Year
 
Ended Ended Ended Ended Ended 
 
3/31/21 3/31/20 3/31/19 3/31/18 3/31/17* 
Class C      
Net asset value, beginning of period 
$ 9.26 $ 9.91 $ 9.94 $ 9.97 $ 9.91 
Increase (decrease) from investment operations: 
     
Net investment income (loss)(a) $ 0.10 $ 0.22 $ 0.22 $ 0.15 $ 0.13 
Net realized and unrealized gain (loss) on investments  0.46(0.63) (0.02) (0.02) 0.07 
Net increase (decrease) from investment operations $ 0.56 $ (0.41) $ 0.20 $ 0.13 $ 0.20 
Distributions to shareowners: 
     
Net investment income $ (0.11) $ (0.24) $ (0.23) $ (0.16) $ (0.14) 
Total distributions $ (0.11) $ (0.24) $ (0.23) $ (0.16) $ (0.14) 
Net increase (decrease) in net asset value $ 0.45 $ (0.65) $ (0.03) $ (0.03) $ 0.06 
Net asset value, end of period 
$ 9.71 $ 9.26 $ 9.91 $ 9.94 $ 9.97 
Total return(b) 
 6.09%
(4.24)% 
1.99% 
1.28% 
2.00% 
Ratio of net expenses to average net assets 
 0.91%
 0.89%
 0.91%
0.92% 0.93% 
Ratio of net investment income (loss) to average net assets 
 1.00%
 2.25%
 2.22%
1.48% 1.27% 
Portfolio turnover rate 
 51%
 100%
 61%
54% 69% 
Net assets, end of period (in thousands) 
$213,396 $300,129 $425,928 $623,642 $568,840 
*     
The Fund was audited by an independent registered public accounting firm other than Ernst & Young LLP.
(a)     
The per share data presented above is based on the average shares outstanding for the period presented.
(b)     
Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges were taken into account.
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 93
 

Financial Highlights (continued)
      
 
Year Year Year Year Year 
 
Ended Ended Ended Ended Ended 
 
3/31/21 3/31/20 3/31/19 3/31/18 3/31/17* 
Class C2      
Net asset value, beginning of period 
$ 9.27 $ 9.91 $ 9.94 $ 9.97 $ 9.91 
Increase (decrease) from investment operations: 
     
Net investment income (loss)(a) $ 0.10 $ 0.21 $ 0.22 $ 0.15 $ 0.13 
Net realized and unrealized gain (loss) on investments 0.46 (0.61) (0.02) (0.02) 0.07 
Net increase (decrease) from investment operations $ 0.56 $ (0.40) $ 0.20 $ 0.13 $ 0.20 
Distributions to shareowners: 
     
Net investment income $ (0.11) $ (0.24) $(0.23) $(0.16) $ (0.14) 
Total distributions $ (0.11) $ (0.24) $(0.23) $(0.16) $ (0.14) 
Net increase (decrease) in net asset value $ 0.45 $ (0.64) $(0.03) $(0.03) $ 0.06 
Net asset value, end of period 
$ 9.72 $ 9.27 $ 9.91 $ 9.94 $ 9.97 
Total return(b) 6.09% (4.13)% 1.98% 1.29% 2.00% 
Ratio of net expenses to average net assets 
0.90% 0.88% 0.91% 0.92% 0.93% 
Ratio of net investment income (loss) to average net assets 
1.00% 2.17% 2.25% 1.47% 1.27% 
Portfolio turnover rate 
51% 100% 61% 54% 69% 
Net assets, end of period (in thousands) 
$19,432 $20,982 $8,604 $8,929 $9,834 
*     
The Fund was audited by an independent registered public accounting firm other than Ernst & Young LLP.
(a)     
The per share data presented above is based on the average shares outstanding for the period presented.
(b)     
Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges were taken into account.
The accompanying notes are an integral part of these financial statements.
94 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

      
 
Year Year Year Year Year 
 
Ended Ended Ended Ended Ended 
 
3/31/21 3/31/20 3/31/19 3/31/18 3/31/17* 
Class K      
Net asset value, beginning of period 
$ 9.29 $ 9.93 $ 9.96 $ 9.99 $ 9.93 
Increase (decrease) from investment operations: 
     
Net investment income (loss)(a) $ 0.15 $ 0.28 $ 0.28 $ 0.20 $ 0.19 
Net realized and unrealized gain (loss) on investments  0.46
(0.62) (0.03) (0.02) 0.06 
Net increase (decrease) from investment operations $ 0.61 $ (0.34) $ 0.25 $ 0.18 $ 0.25 
Distributions to shareowners: 
     
Net investment income $ (0.16) $ (0.30) $ (0.28) $ (0.21) $ (0.19) 
Total distributions $ (0.16) $ (0.30) $ (0.28) $ (0.21) $ (0.19) 
Net increase (decrease) in net asset value $ 0.45 $ (0.64) $ (0.03) $ (0.03) $ 0.06 
Net asset value, end of period 
$ 9.74 $ 9.29 $ 9.93 $ 9.96 $ 9.99 
Total return(b) 
6.64%
(3.60)% 
 2.54%
 1.83%
2.55% 
Ratio of net expenses to average net assets 
0.37% 
 0.36%
 0.37%
 0.38%
0.42% 
Ratio of net investment income (loss) to average net assets 
1.52% 
2.79%
 2.82%
 2.03%
1.92% 
Portfolio turnover rate 
51% 
 100%
 61%
 54%
69% 
Net assets, end of period (in thousands) 
$332,949 $264,405 $274,682 $158,443 $91,666 
*     
The Fund was audited by an independent registered public accounting firm other than Ernst & Young LLP.
(a)     
The per share data presented above is based on the average shares outstanding for the period presented.
(b)     
Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions and the complete redemption of the investment at net asset value at the end of each period.

The accompanying notes are an integral part of these financial statements.

Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 95
 

Financial Highlights (continued)
      
 
Year Year Year Year Year 
 
Ended Ended Ended Ended Ended 
 
3/31/21 3/31/20 3/31/19 3/31/18 3/31/17* 
Class Y      
Net asset value, beginning of period 
$ 9.27 $ 9.92 $ 9.96 $ 9.99 $ 9.93 
Increase (decrease) from investment operations: 
     
Net investment income (loss)(a) $ 0.14 $ 0.27 $ 0.27 $ 0.19 $ 0.17 
Net realized and unrealized gain (loss) on investments  0.48 (0.63)
 (0.04)
 (0.01)
 0.07
Net increase (decrease) from investment operations $ 0.62 $ (0.36) $ 0.23 $ 0.18 $ 0.24 
Distributions to shareowners: 
     
Net investment income $ (0.16) $ (0.29) $ (0.27) $ (0.21) $ (0.18) 
Total distributions $ (0.16) $ (0.29) $ (0.27) $ (0.21) $ (0.18) 
Net increase (decrease) in net asset value $ 0.46 $ (0.65) $ (0.04) $ (0.03) $ 0.06 
Net asset value, end of period 
$ 9.73 $ 9.27 $ 9.92 $ 9.96 $ 9.99 
Total return(b) 
 6.67%
 (3.78)%
 2.37%
 1.76%
 2.46%
Ratio of net expenses to average net assets 
 0.45%
 0.44%
 0.45%
 0.46%
 0.50%
Ratio of net investment income (loss) to average net assets 
 1.45%
 2.69%
 2.74%
 1.94%
 1.70%
Portfolio turnover rate 
 51%
 100%
 61%
 54%
 69%
Net assets, end of period (in thousands) 
$2,335,355 $2,990,790 $3,669,866 $2,509,061 $1,768,502 
*     
The Fund was audited by an independent registered public accounting firm other than Ernst & Young LLP.
(a)     
The per share data presented above is based on the average shares outstanding for the period presented.
(b)     
Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions and the complete redemption of the investment at net asset value at the end of each period.
The accompanying notes are an integral part of these financial statements.
96 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
Notes to Financial Statements | 3/31/21
1. Organization and Significant Accounting Policies
Pioneer Multi-Asset Ultrashort Income Fund (the “Fund”) is one of three portfolios comprising Pioneer Series Trust X, a Delaware statutory trust. The Fund is registered under the Investment Company Act of 1940 as a diversified, open-end management investment company. The investment objective of the Fund is to seek a high level of current income to the extent consistent with a relatively high level of stability of principal.
The Fund offers five classes of shares designated as Class A, Class C, Class C2, Class K and Class Y shares. Each class of shares represents an interest in the same portfolio of investments of the Fund and has identical rights (based on relative net asset values) to assets and liquidation proceeds. Share classes can bear different rates of class-specific fees and expenses, such as transfer agent and distribution fees. Differences in class-specific fees and expenses will result in differences in net investment income and, therefore, the payment of different dividends from net investment income earned by each class. The Amended and Restated Declaration of Trust of the Fund gives the Board of Trustees the flexibility to specify either per-share voting or dollar-weighted voting when submitting matters for shareholder approval. Under per-share voting, each share of a class of the Fund is entitled to one vote. Under dollar-weighted voting, a shareowner’s voting power is determined not by the number of shares owned, but by the dollar value of the shares on the record date. Each share class has exclusive voting rights with respect to matters affecting only that class, including with respect to the distribution plan for that class. There is no distribution plan for Class K or Class Y shares.
Amundi Asset Management US, Inc., an indirect, wholly owned subsidiary of Amundi and Amundi’s wholly owned subsidiary, Amundi USA, Inc., serves as the Fund’s investment adviser (the “Adviser”). Prior to January 1, 2021, the Adviser was named Amundi Pioneer Asset Management, Inc. Amundi Distributor US, Inc., an affiliate of Amundi Asset Management US, Inc., serves as the Fund’s distributor (the “Distributor”).
In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update 2018-13 “Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”) which modifies disclosure requirements for fair value measurements, principally for Level 3 securities and transfers between levels of the fair value hierarchy. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years. The Fund has adopted ASU 2018-13 for the year ended March 31, 2021. The impact to the Fund’s adoption was limited to changes in the Fund’s
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disclosures regarding fair value, primarily those disclosures related to transfers between levels of the fair value hierarchy and disclosure of the range and weighted average used to develop significant unobservable inputs for Level 3 fair value investments, when applicable.
In March 2020, FASB issued an Accounting Standard Update, ASU 2020-04, Reference Rate Reform (Topic 848) — Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”), which provides optional, temporary relief with respect to the financial reporting of contracts subject to certain types of modifications due to the planned discontinuation of the London Interbank Offered Rate (“LIBOR”) and other LIBOR-based reference rates at the end of 2021. The temporary relief provided by ASU 2020-04 is effective for certain reference rate-related contract modifications that occur during the period from March 12, 2020 through December 31, 2022. Management is evaluating the impact of ASU 2020-04 on the Fund’s investments, derivatives, debt and other contracts, if applicable, that will undergo reference rate-related modifications as a result of the reference rate reform.
The Fund is an investment company and follows investment company accounting and reporting guidance under U.S. Generally Accepted Accounting Principles (“U.S. GAAP”). U.S. GAAP requires the management of the Fund to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of income, expenses and gain or loss on investments during the reporting period. Actual results could differ from those estimates.
The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements:
A. Security Valuation
The net asset value of the Fund is computed once daily, on each day the New York Stock Exchange (“NYSE”) is open, as of the close of regular trading on the NYSE.
Fixed-income securities are valued by using prices supplied by independent pricing services, which consider such factors as market prices, market events, quotations from one or more brokers, Treasury spreads, yields, maturities and ratings, or may use a pricing matrix or other fair value methods or techniques to provide an estimated value of the security or instrument. A pricing matrix is a means of valuing a debt security on the basis of current market prices for other debt securities, historical trading patterns in the market for fixed-income securities and/or other factors. Non-U.S. debt securities that are listed on an exchange will be valued at the bid price obtained from an independent third party pricing service.
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When independent third party pricing services are unable to supply prices, or when prices or market quotations are considered to be unreliable, the value of that security may be determined using quotations from one or more broker-dealers.
Loan interests are valued in accordance with guidelines established by the Board of Trustees at the mean between the last available bid and asked prices from one or more brokers or dealers as obtained from Loan Pricing Corporation, an independent third party pricing service. If price information is not available from Loan Pricing Corporation, or if the price information is deemed to be unreliable, price information will be obtained from an alternative loan interest pricing service. If no reliable price quotes are available from either the primary or alternative pricing service, broker quotes will be solicited.
Event-linked bonds are valued at the bid price obtained from an independent third party pricing service. Other insurance-linked securities (including reinsurance sidecars, collateralized reinsurance and industry loss warranties) may be valued at the bid price obtained from an independent pricing service, or through a third party using a pricing matrix, insurance industry valuation models, or other fair value methods or techniques to provide an estimated value of the instrument.
Futures contracts are generally valued at the closing settlement price established by the exchange on which they are traded.
The value of foreign securities is translated into U.S. dollars based on foreign currency exchange rate quotations supplied by a third party pricing source. Trading in non-U.S. equity securities is substantially completed each day at various times prior to the close of the NYSE. The values of such securities used in computing the net asset value of the Fund’s shares are determined as of such times. The Fund may use a fair value model developed by an independent pricing service to value non-U.S. equity securities.
Repurchase agreements are valued at par. Cash may include overnight time deposits at approved financial institutions.
Securities or loan interests for which independent pricing services or broker-dealers are unable to supply prices or for which market prices and/or quotations are not readily available or are considered to be unreliable are valued by a fair valuation team comprised of certain personnel of the Adviser pursuant to procedures adopted by the Fund’s Board of Trustees. The Adviser’s fair valuation team uses fair value methods approved by the Valuation Committee of the Board of Trustees. The Adviser’s fair valuation team is responsible for monitoring
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developments that may impact fair valued securities and for discussing and assessing fair values on an ongoing basis, and at least quarterly, with the Valuation Committee of the Board of Trustees.
Inputs used when applying fair value methods to value a security may include credit ratings, the financial condition of the company, current market conditions and comparable securities. The Fund may use fair value methods if it is determined that a significant event has occurred after the close of the exchange or market on which the security trades and prior to the determination of the Fund’s net asset value. Examples of a significant event might include political or economic news, corporate restructurings, natural disasters, terrorist activity or trading halts. Thus, the valuation of the Fund’s securities may differ significantly from exchange prices, and such differences could be material.
At March 31, 2021, no securities were valued using fair value methods (other than securities valued using prices supplied by independent pricing services, broker-dealers or using a third party insurance industry pricing model).
B. Investment Income and Transactions
Dividend income is recorded on the ex-dividend date, except that certain dividends from foreign securities where the ex-dividend date may have passed are recorded as soon as the Fund becomes aware of the ex-dividend data in the exercise of reasonable diligence.
Interest income, including interest on income-bearing cash accounts, is recorded on the accrual basis. Dividend and interest income are reported net of unrecoverable foreign taxes withheld at the applicable country rates and net of income accrued on defaulted securities.
Interest and dividend income payable by delivery of additional shares is reclassified as PIK (payment-in-kind) income upon receipt and is included in interest and dividend income, respectively.
Principal amounts of mortgage-backed securities are adjusted for monthly paydowns. Premiums and discounts related to certain mortgage-backed securities are amortized or accreted in proportion to the monthly paydowns. All discounts/premiums on purchase prices of debt securities are accreted/amortized for financial reporting purposes over the life of the respective securities, and such accretion/amortization is included in interest income.
Security transactions are recorded as of trade date. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes.
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C. Federal Income Taxes
It is the Fund’s policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its net taxable income and net realized capital gains, if any, to its shareowners. Therefore, no provision for federal income taxes is required. As of March 31, 2021, the Fund did not accrue any interest or penalties with respect to uncertain tax positions, which, if applicable, would be recorded as an income tax expense on the Statement of Operations. Tax returns filed within the prior three years remain subject to examination by federal and state tax authorities.
The amount and character of income and capital gain distributions to shareowners are determined in accordance with federal income tax rules, which may differ from U.S. GAAP. Distributions in excess of net investment income or net realized gains are temporary over distributions for financial statement purposes resulting from differences in the recognition or classification of income or distributions for financial statement and tax purposes. Capital accounts within the financial statements are adjusted for permanent book/tax differences to reflect tax character, but are not adjusted for temporary differences.
At March 31, 2021, the Fund reclassified $27,456 to decrease distributable earnings and $27,456 to increase paid-in capital to reflect permanent book/tax differences. These adjustments have no impact on net assets or the results of operations.
At March 31, 2021, the Fund was permitted to carry forward indefinitely $146,682,362 of short-term losses and $89,695,256 of long-term losses.
The tax character of distributions paid during the years ended March 31, 2021 and March 31, 2020, were as follows:
 
2021 2020 
Distributions paid from: 
 
 
Ordinary income 
$73,465,577 $174,573,245 
Total $73,465,577 $174,573,245 
 
The following shows the components of distributable earnings (losses) on a federal income tax basis at March 31, 2021:
 
2021 
Distributable earnings/(losses): 
 
Undistributed ordinary income 
$ 179,723 
Capital loss carryforward 
(236,377,618) 
Current year dividend payable 
(382,886) 
Unrealized depreciation 
(18,642,511) 
Total $(255,223,292) 
 
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The difference between book-basis and tax-basis unrealized depreciation is attributable to the tax deferral of losses on wash sales, adjustments relating to event-linked bonds, insurance-linked securities and the tax treatment of premium and amortization.
D. Fund Shares
The Fund records sales and repurchases of its shares as of trade date. The Distributor earned $0 in underwriting commissions on the sale of Class A shares during the year ended March 31, 2021.
E. Class Allocations
Income, common expenses and realized and unrealized gains and losses are calculated at the Fund level and allocated daily to each class of shares based on its respective percentage of adjusted net assets at the beginning of the day.
Distribution fees are calculated based on the average daily net asset value attributable to Class A, Class C and Class C2 shares of the Fund, respectively (see Note 5). Class K and Class Y shares do not pay distribution fees. All expenses and fees paid to the Fund’s transfer agent, for its services are allocated among the classes of shares based on the number of accounts in each class and the ratable allocation of related out-of-pocket expenses (see Note 4).
The Fund declares as daily dividends substantially all of its net investment income. All dividends are paid on a monthly basis. Short-term capital gain distributions, if any, may be declared with the daily dividends. Distributions to shareowners are recorded as of the ex-dividend date. Distributions paid by the Fund with respect to each class of shares are calculated in the same manner and at the same time except that net investment income dividends to Class A, Class C, Class C2, Class K and Class Y shares can reflect different transfer agent and distribution expense rates.
F. Risks
The value of securities held by the Fund may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political or regulatory conditions, recessions, the spread of infectious illness or other public health issues, inflation, changes in interest rates, lack of liquidity in the bond markets or adverse investor sentiment. In the past several years, financial markets have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. These conditions may continue, recur, worsen or spread. A general rise in interest rates could adversely affect the price and liquidity of fixed-income securities and could also result in increased redemptions from the Fund.
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At times, the Fund’s investments may represent industries or industry sectors that are interrelated or have common risks, making the Fund more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors. The Fund’s investments in foreign markets and countries with limited developing markets may subject the Fund to a greater degree of risk than investments in a developed market. These risks include disruptive political or economic conditions and the imposition of adverse governmental laws or currency exchange restrictions.
The Fund invests in below-investment-grade (high-yield) debt securities and preferred stocks. Some of these high-yield securities may be convertible into equity securities of the issuer. Debt securities rated below-investment-grade are commonly referred to as “junk bonds” and are considered speculative. These securities involve greater risk of loss, are subject to greater price volatility, and are less liquid, especially during periods of economic uncertainty or change, than higher rated debt securities.
The Fund’s investments, payment obligations and financing terms may be based on floating rates, such as LIBOR (London Interbank Offered Rate). Plans are underway to phase out the use of LIBOR. The UK Financial Conduct Authority (“FCA”) and LIBOR’s administrator, ICE Benchmark Administration (“IBA”), have announced that most LIBOR rates will no longer be published after the end of 2021 and a majority of U.S. dollar LIBOR rates will no longer be published after June 30, 2023. It is possible that the FCA may compel the IBA to publish a subset of LIBOR settings after these dates on a “synthetic” basis, but any such publications would be considered non-representative of the underlying markets. There remains uncertainty regarding the nature of any replacement rate and the impact of the transition from LIBOR on the fund, issuers of instruments in which the fund invests, and financial markets generally.
With the increased use of technologies such as the Internet to conduct business, the Fund is susceptible to operational, information security and related risks. While the Fund’s Adviser has established business continuity plans in the event of, and risk management systems to prevent, limit or mitigate, such cyber-attacks, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified. Furthermore, the Fund cannot control the cybersecurity plans and systems put in place by service providers to the Fund such as Brown Brothers Harriman & Co., the Fund’s custodian and accounting agent, and DST Asset Manager Solutions, Inc., the Fund’s transfer agent. In addition, many beneficial owners of Fund shares hold them through accounts at
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broker-dealers, retirement platforms and other financial market participants over which neither the Fund nor the Adviser exercises control. Each of these may in turn rely on service providers to them, which are also subject to the risk of cyber-attacks. Cybersecurity failures or breaches at the Adviser or the Fund’s service providers or intermediaries have the ability to cause disruptions and impact business operations, potentially resulting in financial losses, interference with the Fund’s ability to calculate its net asset value, impediments to trading, the inability of Fund shareowners to effect share purchases, redemptions or exchanges or receive distributions, loss of or unauthorized access to private shareowner information and violations of applicable privacy and other laws, regulatory fines, penalties, reputational damage, or additional compliance costs. Such costs and losses may not be covered under any insurance. In addition, maintaining vigilance against cyber-attacks may involve substantial costs over time, and system enhancements may themselves be subject to cyber-attacks.
COVID-19
The respiratory illness COVID-19 caused by a novel coronavirus has resulted in a global pandemic and major disruption to economies and markets around the world, including the United States. Global financial markets have experienced extreme volatility and severe losses, and trading in many instruments has been disrupted. Liquidity for many instruments has been greatly reduced for periods of time. Some interest rates are very low and in some cases yields are negative. Some sectors of the economy and individual issuers have experienced particularly large losses. These circumstances may continue for an extended period of time, and may continue to affect adversely the value and liquidity of the Fund’s investments. The ultimate economic fallout from the pandemic, and the long-term impact on economies, markets, industries and individual issuers, are not known. Governments and central banks, including the Federal Reserve in the U.S., have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. These actions have resulted in significant expansion of public debt, including in the U.S. The impact of these measures, and whether they will be effective to mitigate the economic and market disruption, will not be known for some time. The consequences of high public debt, including its future impact on the economy and securities markets, likewise may not be known for some time.
The Fund’s prospectus contains unaudited information regarding the Fund���s principal risks. Please refer to that document when considering the Fund’s principal risks.
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G. Restricted Securities
Restricted Securities are subject to legal or contractual restrictions on resale. Restricted securities generally are resold in transactions exempt from registration under the Securities Act of 1933. Private placement securities are generally considered to be restricted except for those securities traded between qualified institutional investors under the provisions of Rule 144A of the Securities Act of 1933.
Disposal of restricted investments may involve negotiations and expenses, and prompt sale at an acceptable price may be difficult to achieve. Restricted investments held by the Fund at March 31, 2021 are listed in the Schedule of Investments.
H. Insurance-Linked Securities (“ILS”)
The Fund invests in ILS. The Fund could lose a portion or all of the principal it has invested in an ILS, and the right to additional interest or dividend payments with respect to the security, upon the occurrence of one or more trigger events, as defined within the terms of an insurance-linked security. Trigger events, generally, are hurricanes, earthquakes, or other natural events of a specific size or magnitude that occur in a designated geographic region during a specified time period, and/or that involve losses or other metrics that exceed a specific amount. There is no way to accurately predict whether a trigger event will occur, and accordingly, ILS carry significant risk. The Fund is entitled to receive principal, and interest and/or dividend payments so long as no trigger event occurs of the description and magnitude specified by the instrument. In addition to the specified trigger events, ILS may expose the Fund to other risks, including but not limited to issuer (credit) default, adverse regulatory or jurisdictional interpretations and adverse tax consequences.
The Fund’s investments in ILS may include event-linked bonds. ILS also may include special purpose vehicles (“SPVs”) or similar instruments structured to comprise a portion of a reinsurer’s catastrophe-oriented business, known as quota share instruments (sometimes referred to as reinsurance sidecars), or to provide reinsurance relating to specific risks to insurance or reinsurance companies through a collateralized instrument, known as collateralized reinsurance. Structured reinsurance investments also may include industry loss warranties (“ILWs”). A traditional ILW takes the form of a bilateral reinsurance contract, but there are also products that take the form of derivatives, collateralized structures, or exchange-traded instruments.
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Where the ILS are based on the performance of underlying reinsurance contracts, the Fund has limited transparency into the individual underlying contracts, and therefore must rely upon the risk assessment and sound underwriting practices of the issuer. Accordingly, it may be more difficult for the Adviser to fully evaluate the underlying risk profile of the Fund’s structured reinsurance investments, and therefore the Fund’s assets are placed at greater risk of loss than if the Adviser had more complete information. Structured reinsurance instruments generally will be considered illiquid securities by the Fund. These securities may be difficult to purchase, sell or unwind. Illiquid securities also may be difficult to value. If the Fund is forced to sell an illiquid asset, the Fund may be forced to sell at a loss.
I. Repurchase Agreements
Repurchase agreements are arrangements under which the Fund purchases securities from a broker-dealer or a bank, called the counterparty, upon the agreement of the counterparty to repurchase the securities from the Fund at a later date, and at a specific price, which is typically higher than the purchase price paid by the Fund. The securities purchased serve as the Fund’s collateral for the obligation of the counterparty to repurchase the securities. The value of the collateral, including accrued interest, is required to be equal to or in excess of the repurchase price. The collateral for all repurchase agreements is held in safekeeping in the customer-only account of the Fund’s custodian or a sub-custodian of the Fund. The Adviser is responsible for determining that the value of the collateral remains at least equal to the repurchase price. In the event of a default by the counterparty, the Fund is entitled to sell the securities, but the Fund may not be able to sell them for the price at which they were purchased, thus causing a loss to the Fund. Additionally, if the counterparty becomes insolvent, there is some risk that the Fund will not have a right to the securities, or the immediate right to sell the securities.
Open repurchase agreements at March 31, 2021, are disclosed in the Schedule of Investments.
J. Futures Contracts
The Fund may enter into futures transactions in order to attempt to hedge against changes in interest rates, securities prices and currency exchange rates or to seek to increase total return. Futures contracts are types of derivatives. All futures contracts entered into by the Fund are traded on a futures exchange. Upon entering into a futures contract, the Fund is required to deposit with a broker an amount of cash or securities equal to
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the minimum “initial margin” requirements of the associated futures exchange. The amount of cash deposited with the broker as collateral at March 31, 2021, is recorded as “Futures collateral” on the Statement of Assets and Liabilities.
Subsequent payments for futures contracts (“variation margin”) are paid or received by the Fund, depending on the daily fluctuation in the value of the contracts, and are recorded by the Fund as unrealized appreciation or depreciation. Cash received from or paid to the broker related to previous margin movement is held in a segregated account at the broker and is recorded as either “Due from broker for futures” or “Due to broker for futures” on the Statement of Assets and Liabilities. When the contract is closed, the Fund realizes a gain or loss equal to the difference between the opening and closing value of the contract as well as any fluctuation in foreign currency exchange rates where applicable. Futures contracts are subject to market risk, interest rate risk and currency exchange rate risk. Changes in value of the contracts may not directly correlate to the changes in value of the underlying securities. With futures, there is reduced counterparty credit risk to the Fund since futures are exchange-traded and the exchange’s clearinghouse, as counterparty to all exchange-traded futures, guarantees the futures against default.
The average market value of futures contracts open during the year ended March 31, 2021, was $(49,598,323). Open futures contracts outstanding at March 31, 2021, are listed in the Schedule of Investments.
2. Management Agreement
The Adviser manages the Fund’s portfolio. Management fees are calculated daily and paid monthly at the annual rate of 0.35% of the Fund’s average daily net assets up to $1 billion, 0.30% of the next $4 billion of the Fund’s average daily net assets, 0.25% of the next $2.5 billion of the Fund’s average daily net assets and 0.20% of the Fund’s average daily net assets over $7.5 billion. For the year ended March 31, 2021, the effective management fee (excluding waivers and/or assumption of expenses) was equivalent to 0.31% of the Fund’s average daily net assets.
In addition, under the management and administration agreements, certain other services and costs, including accounting, regulatory reporting and insurance premiums, are paid by the Fund as administrative reimbursements. Included in “Due to affiliates” reflected on the Statement of Assets and Liabilities is $199,943 in management fees, administrative costs and certain other reimbursements payable to the Adviser at March 31, 2021.
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3. Compensation of Trustees and Officers
The Fund pays an annual fee to its Trustees. The Adviser reimburses the Fund for fees paid to the Interested Trustees. The Fund does not pay any salary or other compensation to its officers. For the year ended March 31, 2021, the Fund paid $264,271 in Trustees’ compensation, which is reflected on the Statement of Operations as Trustees’ fees. At March 31, 2021, the Fund had a payable for Trustees’ fees on its Statement of Assets and Liabilities of $4,960.
4. Transfer Agent
DST Asset Manager Solutions, Inc. serves as the transfer agent to the Fund at negotiated rates. Transfer agent fees and payables shown on the Statement of Operations and the Statement of Assets and Liabilities, respectively, include sub-transfer agent expenses incurred through the Fund’s omnibus relationship contracts.
In addition, the Fund reimbursed the transfer agent for out-of-pocket expenses incurred by the transfer agent related to shareowner communications activities such as proxy and statement mailings, and outgoing phone calls. For the year ended March 31, 2021, such out-of-pocket expenses by class of shares were as follows:
  
Shareowner Communications: 
 
Class A 
$ 34,064 
Class C 
11,909 
Class C2 
327 
Class K 
326 
Class Y 
93,719 
Total $140,345 
 
5. Distribution Plan
The Fund has adopted a distribution plan (the “Plan”) pursuant to Rule 12b-1 of the Investment Company Act of 1940 with respect to its Class A, Class C and Class C2 shares. Pursuant to the Plan, the Fund pays the Distributor 0.20% of the average daily net assets attributable to Class A shares as compensation for personal services and/or account maintenance services or distribution services with regard to Class A shares. Pursuant to the Plan, the Fund also pays the Distributor 0.50% of the average daily net assets attributable to Class C and Class C2 shares. The fee for Class C and Class C2 shares consists of a 0.25% service fee and a 0.25% distribution fee paid as compensation for personal services and/or account maintenance services or
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distribution services with regard to Class C and Class C2 shares. Included in “Due to affiliates” reflected on the Statement of Assets and Liabilities is $58,469 in distribution fees payable to the Distributor at March 31, 2021.
In addition, redemptions of Class A and Class C2 shares may be subject to a contingent deferred sales charge (“CDSC”). A CDSC of 1.00% may be imposed on redemptions of certain net asset value purchases of Class A shares within 12 months of purchase. Redemptions of Class C2 shares redemptions of shares within 12 months of purchase are subject to a CDSC of 1.00%, based on the lower of cost or market value of shares being redeemed. Shares purchased as part of an exchange remain subject to any CDSC that applied to the original purchase of those shares. There is no CDSC for Class C, Class K and Class Y shares. Proceeds from the CDSCs are paid to the Distributor. For the six months ended March 31, 2021, CDSCs in the amount of $13,375 were paid to the Distributor.
6. Line of Credit Facility
The Fund, along with certain other funds in the Pioneer Family of Funds (the “Funds”), participates in a committed, unsecured revolving line of credit (“credit facility”). Borrowings are used solely for temporary or emergency purposes. The Fund may borrow up to the lesser of the amount available under the credit facility or the limits set for borrowing by the Fund’s prospectus and the 1940 Act. Effective February 4, 2021, the Fund participates in a facility in the amount of $450 million. Prior to February 4, 2021, the Fund participated in a facility in the amount of $300 million. Under such facility, depending on the type of loan, interest on borrowings is payable at the London Interbank Offered Rate (“LIBOR”) plus a credit spread. The Fund also pays both an upfront fee and an annual commitment fee to participate in a credit facility. The upfront fee in the amount 0.10% of the total credit facility is allocated among the participating Funds based on an allocation schedule set forth in the credit agreement. The commitment fee in the amount of 0.25% of the daily unused portion of each lenders commitment is allocated among participating Funds based on an allocation schedule set forth in the credit agreement. For the year ended March 31, 2021, the Fund had no borrowings under the credit facility.
7. Additional Disclosures about Derivative Instruments and Hedging Activities
The Fund’s use of derivatives may enhance or mitigate the Fund’s exposure to the following risks:
Interest rate risk relates to the fluctuations in the value of interest-bearing securities due to changes in the prevailing levels of market interest rates.
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Credit risk relates to the ability of the issuer of a financial instrument to make further principal or interest payments on an obligation or commitment that it has to the Fund.
Foreign exchange rate risk relates to fluctuations in the value of an asset or liability due to changes in currency exchange rates.
Equity risk relates to the fluctuations in the value of financial instruments as a result of changes in market prices (other than those arising from interest rate risk or foreign exchange rate risk), whether caused by factors specific to an individual investment, its issuer, or all factors affecting all instruments traded in a market or market segment.
Commodity risk relates to the risk that the value of a commodity or commodity index will fluctuate based on increases or decreases in the commodities market and factors specific to a particular industry or commodity.
The fair value of open derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) by risk exposure at March 31, 2021, was as follows:
Statement of Assets and Liabilities 
 
 
 
 
 
 
 
Foreign 
 
 
 
Interest Credit Exchange Equity Commodity 
 
Rate Risk Risk Rate Risk Risk Risk 
Assets: 
 
 
 
 
 
Net unrealized 
 
 
 
 
 
appreciation on 
 
 
 
 
 
futures contracts 
$ 4,186,562 
$ — 
$ — 
$ — 
$ — 
Total Value $ 4,186,562 $ — $ — $ — $ — 
 
The effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) on the Statement of Operations by risk exposure at March 31, 2021, was as follows:
Statement of Operations 
 
 
 
 
 
 
 
 
Foreign 
 
 
 
Interest Credit Exchange Equity Commodity 
 
Rate Risk Risk Rate Risk Risk Risk 
Net realized gain (loss) on: 
 
 
 
 
 
Futures contracts 
$ 3,633,631 
$ — 
$ — 
$ — 
$ — 
Total Value $ 3,633,631 $ — $ — $ — $ — 
Change in net unrealized 
 
 
 
 
 
appreciation 
 
 
 
 
 
(depreciation) on: 
 
 
 
 
 
Futures contracts 
$ 4,186,562 
$ — 
$ — 
$ — 
$ — 
Total Value $ 4,186,562 $ — $ — $ — $ — 
 
110 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

8. Unfunded Loan Commitments
The Fund may enter into unfunded loan commitments. Unfunded loan commitments may be partially or wholly unfunded. During the contractual period, the Fund is obliged to provide funding to the borrower upon demand. A fee is earned by the Fund on the unfunded loan commitment and is recorded as interest income on the Statement of Operations. Unfunded loan commitments are fair valued in accordance with the valuation policy described in Footnote 1A and unrealized appreciation or depreciation, if any, is recorded on the Statement of Assets and Liabilities.
As of March 31, 2021, the Fund had the following unfunded loan commitments outstanding:
     
 
 
 
 
Unrealized 
 
 
 
 
Appreciation/ 
Loan Principal Cost Value (Depreciation) 
Service Logic Acquisition, Inc. 
$246,269 
$243,951 
$246,577 
$ 2,626 
WMG Acquisition Corp. 
500,000 
500,000 
498,125 
$(1,875) 
Total Value $746,269 $743,951 $744,702 $ 751 
 
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 111
 
Report of Independent Registered Public Accounting Firm
To the Board of Trustees of Pioneer Series Trust X and the Shareholders of Pioneer Multi-Asset Ultrashort Income Fund:
Opinion on the Financial Statements
We have audited the accompanying statement of assets and liabilities of Pioneer Multi-Asset Ultrashort Income Fund (the “Fund”) (one of the funds constituting Pioneer Series Trust X (the “Trust”)), including the schedule of investments, as of March 31, 2021, and the related statement of operations for the year then ended, the statements of changes in net assets for each of the two years in the period then ended, the financial highlights for each of the four years in the period then ended and the related notes (collectively referred to as the “financial statements”). The financial highlights for the period ended March 31, 2017 were audited by another independent registered public accounting firm whose report, dated May 26, 2017, expressed an unqualified opinion on those financial highlights. In our opinion, the financial statements present fairly, in all material respects, the financial position of Pioneer Multi-Asset Ultrashort Income Fund (one of the funds constituting Pioneer Series Trust X) at March 31, 2021, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended, and its financial highlights for each of the four years in the period then ended in conformity with U.S. generally accepted accounting principles.
Basis for Opinion
These financial statements are the responsibility of the Trust’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (“PCAOB”) and are required to be independent with respect to the Trust in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Trust is not required to have, nor were we engaged to perform, an audit of the Trust’s internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting, but not for the purpose of expressing an opinion on the effectiveness of the Trust’s internal control over financial reporting. Accordingly, we express no such opinion.
112 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our procedures included confirmation of securities owned as of March 31, 2021, by correspondence with the custodian and brokers or by other appropriate auditing procedures where replies from brokers were not received. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.
We have served as the auditor of one or more Amundi Pioneer investment companies since 2017.
Boston, Massachusetts
May 27, 2021
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 113

 
Additional Information (unaudited)
Qualified interest income is exempt from nonresident alien (NRA) tax withholding. The percentage of the Fund’s ordinary income distributions derived from qualified interest income was 76.45%.
114 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Trustees, Officers and Service Providers
Investment Adviser and Administrator
Amundi Asset Management US, Inc.

Custodian and Sub-Administrator
Brown Brothers Harriman & Co.

Independent Registered Public Accounting Firm
Ernst & Young LLP

Principal Underwriter
Amundi Distributor US, Inc.

Legal Counsel
Morgan, Lewis & Bockius LLP

Transfer Agent
DST Asset Manager Solutions, Inc.
Proxy Voting Policies and Procedures of the Fund are available without charge, upon request, by calling our toll free number (1-800-225-6292). Information regarding how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is publicly available to shareowners at www.amundi.com/us. This information is also available on the Securities and Exchange Commission’s web site at www.sec.gov.
Trustees and Officers
The Fund’s Trustees and officers are listed below, together with their principal occupations and other directorships they have held during at least the past five years. Trustees who are interested persons of the Fund within the meaning of the 1940 Act are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a Trustee of each of the 45 U.S. registered investment portfolios for which Amundi US serves as investment adviser (the “Pioneer Funds”). The address for all Trustees and all officers of the Fund is 60 State Street, Boston, Massachusetts 02109.
The Statement of Additional Information of the Fund includes additional information about the Trustees and is available, without charge, upon request, by calling 1-800-225-6292.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 115
 

Independent Trustees
    
Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Trustee 
Thomas J. Perna (70) Chairman of the Board and Trustee 
Trustee since 2011. Serves until a successor trustee is elected or earlier retirement or removal. 
Private investor (2004 – 2008 and 2013 – present); Chairman (2008 – 2013) and Chief Executive Officer (2008 – 2012), Quadriserv, Inc. (technology products for securities lending industry); and Senior Executive Vice President, The Bank of New York (financial and securities services) (1986 – 2004) 
Director, Broadridge Financial Solutions, Inc. (investor communications and securities processing provider for financial services industry) (2009 – present); Director, Quadriserv, Inc. (2005 – 2013); and Commissioner, New Jersey State Civil Service Commission (2011 – 2015) 
 
 
 
 
 
 
 
 
John E. Baumgardner, 
Trustee since 2019. Serves until a successor trustee is elected or earlier retirement or removal. 
Of Counsel (2019 – present), Partner (1983-2018), Sullivan & Cromwell LLP (law firm). 
Chairman, The Lakeville Journal Company, LLC, (privately-held community newspaper group) (2015-present) 
Jr. (70) 
Trustee 
 
 
 
Diane Durnin (64) 
Trustee since 2019. Serves until a successor trustee is elected or earlier retirement or removal. 
Managing Director - Head of Product Strategy and Development, BNY Mellon Investment Management (investment management firm) (2012-2018); Vice Chairman – The Dreyfus Corporation (2005 – 2018): Executive Vice President Head of Product, BNY Mellon Investment Management (2007-2012); Executive Director- Product Strategy, Mellon Asset Management (2005-2007); Executive Vice President Head of Products, Marketing and Client Service, Dreyfus Corporation (investment management firm) (2000-2005); and Senior Vice President Strategic Product and Business Development, Dreyfus Corporation (1994-2000)
None 
Trustee 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


 
116 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

    
Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Trustee 
Benjamin M. Friedman (76) 
Trustee since 2011. 
Serves until a successor 
trustee is elected 
or earlier retirement 
or removal. 
William Joseph Maier Professor of Political Economy, Harvard University (1972 – present) 
 
 
 
Trustee, Mellon Institutional Funds Investment Trust and Mellon Institutional Funds Master Portfolio (oversaw 17 portfolios in fund complex) (1989 - 2008) 
Trustee 
 
 
 
Craig C. MacKay (58)* 
Trustee since 2021. Serves until a successor trustee is elected or earlier retirement or removal. 
 
Partner, England & Company, LLC (advisory firm) (2012 – present); Group Head – Leveraged Finance Distribution, Oppenheimer & Company (investment bank) (2006 – 2012); Group Head – Private Finance & High Yield Capital Markets Origination, SunTrust Robinson Humphrey (investment bank) (2003 – 2006); and Founder and Chief Executive Officer, HNY Associates, LLC (investment bank) (1996 – 2003) 
Board Member of Carver Bancorp, Inc. (holding company) and Carver Federal Savings Bank, NA (2017 – present); Advisory Council Member, MasterShares ETF (2016 – 2017); Advisory Council Member, The Deal (financial market information publisher) (2015 – 2016); Board Co-Chairman and Chief Executive Officer, Danis Transportation Company (privately-owned commercial carrier) (2000 – 2003); Board Member and Chief Financial Officer, Customer Access Resources (privately-owned teleservices company) (1998 – 2000); Board Member, Federation of Protestant Welfare Agencies (human services agency) (1993 – present); and Board Treasurer, Harlem Dowling Westside Center (foster care agency) (1999 – 2018) 
Trustee 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
*     
Mr. MacKay was appointed as a Trustee effective March 22, 2021.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 117

Independent Trustees (continued)
    
Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Trustee 
Lorraine H. Monchak (64) 
Trustee since 2017. (Advisory Trustee from 
2014 - 2017). Serves until a successor trustee is elected or earlier retirement or removal. 
 
 
 
 
Chief Investment Officer, 1199 SEIU Funds (healthcare workers union 
pension funds) (2001 – present); Vice President – International Investments Group, American International Group, Inc. (insurance company) (1993 – 2001); Vice President – Corporate Finance and Treasury Group, Citibank, N.A. (1980 – 1986 and 1990 – 1993); Vice President – Asset/Liability Management Group, Federal Farm Funding Corporation (government-sponsored issuer of debt securities) (1988 – 1990); Mortgage Strategies Group, Shearson Lehman Hutton, Inc. (investment bank) (1987 – 1988); and Mortgage Strategies Group, Drexel Burnham Lambert, Ltd. (investment bank) (1986 – 1987) 
None 
 
 
 
 
 
 
 
 
 
Trustee 
 
 
 
 
 
 
 
 
Marguerite A. Piret (72) 
Trustee since 2011. 
Serves until a successor trustee is elected or earlier retirement or removal. 
 
Chief Financial Officer, American Ag Energy, Inc. (controlled environment and agriculture company) (2016 – present); and President and Chief Executive Officer, Metric Financial Inc. (formerly known as Newbury Piret Company) (investment banking firm) (1981 – 2019) 
 
 
Director of New America High Income Fund, Inc. (closed-end investment company) (2004 – present); and Member, Board of Governors, Investment Company Institute (2000 – 2006) 
Trustee 
 
 
 
 
Fred J. Ricciardi (74) 
Trustee since 2014. 
Serves until a successor 
trustee is elected 
or earlier retirement 
or removal. 
 
 
 
 
Private investor (2020 – present); Consultant (investment company services) (2012 – 2020); Executive Vice President, BNY Mellon (financial and investment company services) (1969 – 2012); Director, BNY International Financing Corp. (financial services) (2002 – 2012); Director, Mellon Overseas Investment Corp. (financial services) (2009 – 2012); Director, Financial Models (technology) (2005-2007); Director, BNY Hamilton Funds, Ireland (offshore investment companies) (2004-2007); Chairman/Director, AIB/BNY Securities Services, Ltd., Ireland (financial services) (1999-2006); and Chairman, BNY Alternative Investment Services, Inc. (financial services) (2005-2007) 
None 
 
 
 
 
 
 
 
 
Trustee 
 
 
 
 
 
 
 
 
118 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
Interested Trustees
Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Trustee 
Lisa M. Jones (59)** 
Trustee since 2017. 
Serves until a successor 
trustee is elected 
or earlier retirement 
or removal 
 
 
 
 
 
 
Director, CEO and President of Amundi US, Inc. (investment management firm) (since September 2014); Director, CEO and President of Amundi Asset Management US, Inc. (since September 2014); Director, CEO and President of Amundi Distributor US, Inc. (since September 2014); Director, CEO and President of Amundi Asset Management US, Inc. (since September 2014); Chair, Amundi US, Inc., Amundi Distributor US, Inc. and Amundi Asset Management US, Inc. (September 2014 – 2018); Managing Director, Morgan Stanley Investment Management (investment management firm) (2010 – 2013); Director of Institutional Business, CEO of International, Eaton Vance Management (investment management firm) (2005 – 2010); and Director of Amundi Holdings US, Inc. (since 2017) 
None 
 
 
 
 
 
 
 
 
 
 
Trustee, President and 
Chief Executive Officer 
 
 
 
 
 
 
 
 
Kenneth J. Taubes (62)** 
Trustee since 2014. 
Serves until a successor 
trustee is elected 
or earlier retirement 
or removal 
 
 
Director and Executive Vice President (since 2008) and Chief Investment Officer, U.S. (since 2010) of Amundi US, Inc. (investment management firm); Director and Executive Vice President and Chief Investment Officer, U.S. of Amundi US (since 2008); Executive Vice President and Chief Investment Officer, U.S. of Amundi Asset Management US, Inc. (since 2009); Portfolio Manager of Amundi US (since 1999); and Director of Amundi Holdings US, Inc. (since 2017)
None 
 
 
 
 
 
 
Trustee 
 
 
 
 
 
**     
Ms. Jones and Mr. Taubes are Interested Trustees because they are officers or directors of the fund’s investment adviser and certain of its affiliates.
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 119

Fund Officers*
Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Officer 
Christopher J. Kelley (56) 
Since 2011. Serves at the discretion of the Board 
 
Vice President and Associate General Counsel of Amundi US since 
January 2008; Secretary and Chief Legal Officer of all of the Pioneer Funds 
since June 2010; Assistant Secretary of all of the Pioneer Funds from 
September 2003 to May 2010; and Vice President and Senior Counsel of 
Amundi US from July 2002 to December 2007 
None 
 
 
 
 
Secretary and Chief 
Legal Officer 
 
Carol B. Hannigan (60) 
Since 2011. Serves at the discretion of the Board 
 
Fund Governance Director of Amundi US since December 2006 and Assistant Secretary of all the Pioneer Funds since June 2010; Manager – Fund Governance of Amundi US from December 2003 to November 2006; and Senior Paralegal of Amundi US from January 2000 to November 2003 
None 
 
 
 
Assistant Secretary 
 
 
Thomas Reyes (58) 
Assistant Secretary 
 
Since 2011. Serves at the discretion of the Board 
Assistant General Counsel of Amundi US since May 2013 and Assistant Secretary of all the Pioneer Funds since June 2010; and Counsel of Amundi US from June 2007 to May 2013 
None 
 
 
Anthony J. Koenig, Jr. (57) 
Since 2021. Serves at the discretion of the Board 
 
Senior Vice President – Fund Treasury of Amundi US; Treasurer of all of the Pioneer Funds since May 2021; Assistant Treasurer of all of the Pioneer Funds from January 2021 to May 2021; and Chief of Staff, US Investment Management of Amundi US from May 2008 to January 2021 
None 
 
 
 
Treasurer and Chief 
Financial and 
Accounting Officer 
Luis I. Presutti (55) 
Since 2011. Serves at the discretion of the Board 
Director – Fund Treasury of Amundi US since 1999; and Assistant Treasurer of all of the Pioneer Funds since 1999 
 
None 
 
 
Assistant Treasurer 
 
Gary Sullivan (62) 
Since 2011. Serves at the discretion of the Board 
Senior Manager – Fund Treasury of Amundi US since 2012; and Assistant Treasurer of all of the Pioneer Funds since 2002 
 
None 
 
 
Assistant Treasurer 
 
*     
Effective April 30, 2021, Mark E. Bradley is no longer Treasurer of the Fund.
120 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

Name, Age and Position Term of Office and 
 
Other Directorships 
Held With the Fund Length of Service Principal Occupation Held by Officer 
Antonio Furtado (38) 
Since 2020. Serves 
at the discretion of 
the Board 
Fund Oversight Manager – Fund Treasury of Amundi US since 2020; Assistant Treasurer of all of the Pioneer Funds since 2020; and Senior Fund Treasury Analyst from 2012 - 2020 
None 
Assistant Treasurer 
 
 
 
John Malone (50) 
Since 2018. Serves 
at the discretion of 
the Board 
Managing Director, Chief Compliance Officer of Amundi US Asset Management; Amundi Asset Management US, Inc.; and the Pioneer Funds since September 2018; and Chief Compliance Officer of Amundi Distributor US, Inc. since January 2014.
None 
Chief Compliance Officer 
 
 
 
Kelly O’Donnell (50) 
Since 2011. Serves at the discretion of the Board 
Vice President – Amundi Asset Management; and Anti-Money Laundering Officer of all the Pioneer Funds since 2006 
 
None 
Anti-Money 
 
Laundering Officer 
 
 
Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 121
 

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Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21 123
 

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124 Pioneer Multi-Asset Ultrashort Income Fund | Annual Report | 3/31/21
 

How to Contact Amundi
We are pleased to offer a variety of convenient ways for you to contact us for assistance or information.
  
Call us for: 
 
Account Information, including existing accounts, 
 
new accounts, prospectuses, applications 
 
and service forms 
1-800-225-6292 
FactFoneSM for automated fund yields, prices, 
 
account information and transactions 
1-800-225-4321 
Retirement plans information 1-800-622-0176 
 
Write to us:

Amundi
P.O. Box 219427
Kansas City, MO 64121-9427
Our toll-free fax 1-800-225-4240 
Our internet e-mail address us.askamundi@amundi.com/us 
(for general questions about Amundi only) 
 
 
Visit our web site: www.amundi.com/us. 
 
 
This report must be preceded or accompanied by a prospectus.
The Fund files a complete schedule of portfolio holdings with the Securities and Exchange Commission for the first and third quarters of each fiscal year as an exhibit to its reports on Form N-PORT. Shareholders may view the filed Form N-PORT by visiting the Commission’s web site at https://www.sec.gov.
 

Amundi Asset Management US, Inc.
60 State Street
Boston, MA 02109
www.amundi.com/us
Securities offered through Amundi Distributor US, Inc.,
60 State Street, Boston, MA 02109
Underwriter of Pioneer Mutual Funds, Member SIPC
© 2021 Amundi Asset Management US, Inc. 25671-09-0521



Pioneer Fundamental Growth Fund
Annual Report | March 31, 2021
     
A: PIGFX C: FUNCX K: PFGKX R: PFGRX Y: FUNYX 
 
Paper copies of the Fund’s shareholder reports are no longer sent by mail, unless you specifically request paper copies of the reports from the Fund or from your financial intermediary, such as a broker-dealer, bank or insurance company. Instead, the reports are available on the Fund’s website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.
You may elect to receive all future reports in paper free of charge. If you invest directly with the Fund, you can inform the Fund that you wish to continue receiving paper copies of your shareholder reports by calling 1-800-225-6292.
If you invest through a financial intermediary, you can contact your financial intermediary to request that you continue to receive paper copies of your shareholder reports. Your election to receive reports in paper will apply to all funds held in your account if you invest through your financial intermediary or all funds held within the Pioneer Fund complex if you invest directly.


 

visit us: www.amundi.com/us

 

Table of Contents
 
13 
14 
15 
20 
22 
26 
35 
45 
Additional Information
 47 
48 
 
Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 1



President’s Letter


Dear Shareholders,
The first few months of 2021 have brought some better news on the COVID-19 global pandemic front, as the deployment of the first approved COVID-19 vaccines is well underway, with expectations for widespread vaccine distribution by the middle of the year. In general, COVID-19 cases and related hospitalizations have been on the decline in the US, despite a few problematic “hot spots” in some states, and that has had a positive effect on overall market sentiment.
While there may finally be a light visible at the end of the pandemic tunnel, the long-term impact on the global economy from COVID-19, while currently unknown, is likely to be considerable. It is clear that several industries have already felt greater effects than others, and the markets, which do not thrive on uncertainty, have been volatile. With that said, in the first few months of 2021, equity markets and other so-called “riskier” assets, such as high-yield bonds, have outperformed investments regarded as less risky, such as government debt. In addition, we’ve witnessed the long-awaited rebound in the performance of cyclical stocks, or stocks of companies with greater exposure to the ebbs and flows of the economic cycle, as investors have appeared to embrace the potential for a more widespread reopening of the economy in the coming months. Additional fiscal stimulus from the US government in recent months has also helped provide some market momentum.
However, despite the dramatic market rebound since its March 2020 low point, volatility has remained elevated, with momentum rising and falling on seemingly every bit of positive or negative news about the virus. In addition, the recent US Presidential and Congressional elections have resulted in a power shift in Washington, DC, and that most likely portends some changes in fiscal policy above and beyond just additional pandemic-related stimulus. That, too, could lead to increased market volatility as investors analyze the various tax and spending plans, and wait to see what proposed policy alterations actually become law.
With the advent of COVID-19 in early 2020, we implemented our business continuity plan according to the new COVID-19 guidelines, and most of our employees have been working remotely since March 2020. To date, our operating environment has faced no interruption. I am proud of the careful planning that has taken place and confident we can maintain this environment for as long as is prudent. History in the making for a company that first opened its doors way back in 1928.

2 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 
Since 1928, Amundi US’s investment process has been built on a foundation of fundamental research and active management, principles which have guided our investment decisions for more than 90 years. We believe active management – that is, making active investment decisions – can help mitigate the risks during periods of market volatility. As 2020 has reminded us, investment risk can arise from a number of factors in today’s global economy, including slower or stagnating growth, changing U.S. Federal Reserve policy, oil price shocks, political and geopolitical factors and, unfortunately, major public health concerns such as a viral pandemic.
At Amundi US, active management begins with our own fundamental, bottom-up research process. Our team of dedicated research analysts and portfolio managers analyzes each security under consideration, communicating directly with the management teams of the companies issuing the securities and working together to identify those securities that best meet our investment criteria for our family of funds. Our risk management approach begins with each and every security, as we strive to carefully understand the potential opportunity, while considering any and all risk factors.
Today, as investors, we have many options. It is our view that active management can serve shareholders well, not only when markets are thriving, but also during periods of market stress.
As you consider your long-term investment goals, we encourage you to work with your financial professional to develop an investment plan that paves the way for you to pursue both your short-term and long-term goals.
We remain confident that the current crisis, like others in human history, will pass, and we greatly appreciate the trust you have placed in us and look forward to continuing to serve you in the future.
Sincerely,
Lisa M. Jones
Head of the Americas, President and CEO of US
Amundi Asset Management US, Inc.
May 2021
Any information in this shareowner report regarding market or economic trends or the factors influencing the Fund’s historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results.

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 3

 

Portfolio Management Discussion | 3 / 31/ 21
US equity markets rebounded sharply during the 12-month period ended March 31, 2021, as investors regained confidence following the bear market sell-off driven by the onset of the COVID-19 pandemic in early 2020. In the following interview, Andrew Acheson and Paul Cloonan discuss the factors that affected the performance of Pioneer Fundamental Growth Fund during the 12-month period. Mr. Acheson, Managing Director, Director of Growth, US, and a portfolio manager at Amundi Asset Management US, Inc. (Amundi US), and Mr. Cloonan*, a senior vice president and a portfolio manager at Amundi US, are responsible for the day-to-day management of the Fund.
Q How did the Fund perform during the 12-month period ended March 31, 2021?
A Pioneer Fundamental Growth Fund’s Class A shares returned 55.55% at net asset value during the 12-month period ended March 31, 2021, while the Fund’s benchmark, the Russell 1000 Growth Index, returned 62.74%.During the same period, the average return of the 1,282 mutual funds in Morningstar’s Large Growth Funds category was 63.57%.
Q How would you describe the investment environment for domestic equity investors during the 12-month period ended March 31, 2021?
A While markets endured bouts of volatility, the 12-month period saw equities generally trend higher and finish with notable gains. In the wake of COVID-19-driven shutdowns in the spring of 2020, unprecedented levels of monetary and fiscal stimulus from the US Federal Reserve (Fed) and the US government boosted liquidity in the financial system and quickly generated a sense of optimism that the economic effects of the pandemic, though severe, would be short-lived. Corporate earnings results added to investors’ upbeat outlook, with second-quarter 2020 earnings surpassing consensus estimates by an unprecedented margin of more than 20%.
Markets continued to rally during the summer of 2020, as many US businesses reopened after the initial shutdowns aimed at curbing the spread of the COVID-19 virus. The economy at that time showed several signs of strength, with a surge in consumer spending and housing sales.
*  Effective June 30, 2021, Mr. Cloonan will no longer be a portfolio manager on the Fund. Mr. Acheson will become lead portfolio manager and will continue to be responsible for the day-to-day    management of the Fund, along with Yves Raymond, a vice president and portfolio manager at Amundi US, and David Chamberlain, a vice president and portfolio manager at Amundi US, both of whom became portfolio managers on the Fund in April 2021.

4 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 

The Fed, which had lowered the target range of the federal funds rate effectively to zero at the height of the pandemic-induced market slump, signaled that interest rates would likely remain low for several years, lending support to equity valuations and making fixed-income alternatives far less attractive to investors. However, after reaching new highs in early September 2020, markets became choppier as an uptick in COVID-19 case counts and uncertainty about the November US presidential election combined to prompt a pullback.
Markets for riskier assets, including equities, once again surged higher following the election, and additional stimulus approved by US lawmakers near the end of 2020 further boosted investors’ confidence, as did the emergency-use approval of the first COVID-19 vaccines and the accompanying rollout of vaccine distributions, which market participants viewed as a possible “light at the end of the tunnel” with regard to the pandemic.
The first quarter of 2021 saw markets continue to rally, as the accelerated pace of COVID-19 vaccine distributions, the passage of another $1.9 trillion fiscal stimulus package by the US government, and further supportive messaging from the Fed helped investors gain confidence in the prospects for a sharp economic recovery later in the calendar year.
Growth stocks outperformed value stocks by a wide margin during the 12-month period, extending a streak of outperformance for growth over value that has lasted for several years. Early in the period, high-valuation growth stocks posted the best returns, especially within the information technology sector. As the rally continued, the consumer discretionary sector overtook information technology to lead performance within the Fund’s benchmark, the Russell 1000 Growth Index, for the first half of the 12-month period. However, a market rotation towards value stocks began in earnest during the fourth quarter of 2020 and gained momentum over the final months of the period. In fact, value stocks, as measured by the Russell 1000 Value Index, outperformed growth stocks, as measured by the Russell 1000 Growth Index (the Russell Index), by more than 10 percentage points during the first quarter of 2021 (January through March), which represented the most dramatic quarterly outperformance by value over growth in 20 years.

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 5

 

Q What factors detracted from the Fund’s performance relative to the benchmark Russell Index during the 12-month period ended March 31, 2021?
A During the 12-month period, we maintained our traditional discipline of focusing the Fund’s investments on shares of what we viewed as higher-quality corporations with stable businesses and steady earnings. Given our focus on trying to mitigate risk, the Fund’s performance has typically lagged the return of the benchmark when markets have appreciated significantly, particularly when more-speculative stocks drove the market’s momentum, which was the case for most of the 12-month period.
Three key factors were the biggest detractors from the Fund’s benchmark-relative performance over the 12-month period. First, investors have largely favored high-growth, high-valuation stocks ever since the market began rebounding from the pandemic-induced sell-off of one year ago, and the returns of stocks with the highest price-to-earnings ratios within the Russell Index have far exceeded the overall return of the Fund’s benchmark. We have maintained portfolio underweights to those types of stocks, due to our concerns about the sustainability of their valuations. While many of the stocks started to underperform in the latter part of the 12-month period, we believe there is still a very significant downside risk to owning shares in what we view as those more-speculative equities.
The second factor was the unique nature of the COVID-19 economic contraction, which had a negative effect on some Fund holdings that have historically acted more defensively during recessionary periods. For instance, the off-price retail industry has typically been resistant to recessionary conditions over time. However, store closures due to COVID-19 restrictions caused sales and profits of such retailers to decline sharply, and the slow return to more “normal” business conditions has continued to weigh on the performance of those companies.
Finally, the weighting of the largest five stocks within the Russell Index has grown to record levels. The benchmark’s concentration in a handful of stocks has raised risk-management concerns, in our view, especially as the concentration has also resulted in unprecedented exposure to a single sector within the Russell Index: information technology. In seeking to manage portfolio risk, we have deliberately maintained below-benchmark exposure to those largest five stocks, even as they have outperformed and thus detracted from the Fund’s relative returns.

6 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 

Q Which individual stocks detracted from the Fund’s benchmark-relative performance during the 12-month period ended March 31, 2021?
A The two biggest individual detractors from the Fund’s benchmark-relative returns during the 12-month period were the portfolio’s lack of exposure to Tesla, the manufacturer of electric vehicles, and an underweight position in technology giant Apple, as both stocks climbed sharply over the past year. Tesla’s stock valuation has become excessive, in our view, and Apple’s weighting in the Russell Index at times exceeded 11% during the period.
Portfolio overweights that notably detracted from the Fund’s benchmark-relative returns for the 12-month period included a position in snack-and-beverage company PepsiCo. Cost pressures weighed on the company’s earnings throughout 2020 as investments in its marketing and production capacities led PepsiCo to divert capital away from stock repurchases. However, signs toward the end of the period pointed to a potential recovery and rising market shares in key segments of the company’s business.
An overweight position in insurance giant Progressive also detracted from the Fund’s benchmark-relative performance for the 12-month period. Progressive’s profits have tended to be more resilient during economic downturns, as auto insurance coverage is mandatory in nearly all US states. Moreover, auto accidents and resulting insurance claims have typically declined during times of rising unemployment, due to fewer miles being driven by the company’s customers. However, as the economy reopened and driving behavior began returning to pre-pandemic levels, investors’ sentiment towards Progressive waned. We have retained the Fund’s position, as we still believe Progressive’s long-term outlook is positive, given its market-share gains and general profitability.
Q Which investments contributed positively to the Fund’s benchmark-relative performance during the 12-month period ended March 31, 2021?
A The largest individual contributor to the Fund’s performance relative to the benchmark for the period was a position in PayPal. PayPal’s large-scale technology platform for digital and mobile payments has benefited from the gradual, secular shift towards a cashless society, and the COVID-19 pandemic has helped accelerate the adoption of electronic

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 7

 

payments across the globe. The introduction of cryptocurrency services also contributed to growth in the latter part of the 12-month period. We believe that PayPal could continue to do well if the economy recovers from the pandemic and consumers eventually increase spending in response. The company has featured high returns on capital and a wide “moat” around its business, with a network of more than 375 million users and 29 million merchants. (A wide moat is defined as a type of sustainable competitive advantage possessed by a business that makes it difficult for rivals to wear down its market share.)
Shares of tool-and-hardware manufacturer Stanley Black & Decker also strongly contributed positively to the Fund’s benchmark-relative returns for the 12-month period. The home-improvement industry has been resilient during the pandemic, as individuals working from home have looked to make renovations to accommodate their changing needs. In response, home-improvement retailers have overcome uncertainty about the broader economy and restocked their inventories, which has helped boost Stanley Black & Decker’s revenues. We believe the company’s strong brands, innovation, and global distribution capabilities give it competitive advantages that could sustain solid returns on capital.
Finally, online search and cloud-infrastructure company Alphabet was a notable positive contributor to the Fund’s relative performance. Alphabet for a time had lagged behind many of its peers among large technology companies, but the company saw its search-based advertising business recover during the 12-month period, and pandemic-driven digital investments also boosted demand in the cloud-computing market. We believe those favorable trends may continue for the foreseeable future.
Q Did the Fund have any exposure to derivative securities during the 12-month period ended March 31, 2021?
A No, the Fund had no exposure to derivatives during the 12-month period.
Q What were some of the notable additions you made to the Fund’s portfolio during the 12-month period ended March 31, 2021?
A Early in the period, we initiated a position in auto-auction firm Copart, which provides auction services to insurance companies related to the salvage of damaged vehicles. The company has consistently generated solid returns on growth capital, driven by its scale and efficiency advantages, and the increase in the number of vehicles considered to be “total losses” in accidents has been another key factor in an increase in the amount of cars sold through auction providers.
8 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 

Later in 2020, we added shares of semiconductor chip-maker Qualcomm to the portfolio. Qualcomm owns numerous patents for the technologies that make up the backbone of 3G, 4G, and coming 5G networks. The company recently reported better-than-expected quarterly earnings results, and we believe that Qualcomm’s intellectual property represents a large and sustainable competitive advantage that could result in profitable growth for the foreseeable future. Other new positions added to the Fund during the period were health insurer Humana and off-price retailer TJX. Humana has benefited from the aging population’s positive effects on the sales of its Medicare Advantage products, which are supplemental insurance plans for Medicare recipients, while TJX has participated in the home-goods boom and has featured a higher-income customer base than fellow Fund holding and industry peer Ross Stores.
Toward the end of the period, we added life-science toolmaker and diagnostic specialist Danaher to the portfolio. The company has generated strong organic growth and returns on capital as its research-and-development activities and pharmaceutical pipeline work have grown. We also have seen opportunities for growth in Danaher’s environment solutions segment. Finally, we added shares of oilfield-services company Schlumberger to the portfolio during the period, as the energy market has shown signs of recovery after a significant slump in the early months of 2020, particularly in the first quarter. Schlumberger has shifted toward higher-margin technological and intellectual property-based services, and we believe its position as one of the market leaders in its industry potentially gives the company competitive advantages over its peers.
Q What were some of the noteworthy positions sold from the Fund’s portfolio during the 12-month period ended March 31, 2021?
A During the period, we exited the Fund’s position in Elanco Animal Health. The company has significantly increased its debt level in order to purchase Bayer’s animal health division. (Bayer is not a Fund holding.) We believe that the increased leverage has raised the company’s risk profile to a degree inconsistent with our focus on quality when picking stocks for the Fund’s portfolio. Moreover, challenges involved in executing a major merger integration during the pandemic have created additional risks for Elanco. Later in the period, we also sold the Fund’s position in Elanco’s industry peer Zoetis, once the stock reached a valuation that no longer seemed justifiable to us, even given a positive outlook for the company’s business.

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 9

 

We also sold the Fund’s position in Walmart early in the second half of the 12-month period, primarily due to valuation. Walmart’s successful omni-channel strategy has helped it gain meaningful market share in e-commerce, but the industry has remained fiercely competitive, which could weigh on the company’s returns on capital. Similarly, we closed the Fund’s position in consumer-products company Colgate-Palmolive after having bought shares earlier in the 12-month period. We had made the purchase at what we believed was an opportune moment, but we now think Colgate-Palmolive will have to invest more heavily in its business, which could hurt the company’s profit margins.
We sold the Fund’s shares of materials and chemical company Ecolab during the first quarter of 2021. The stock has traded above our estimate of fair value, and we believe it could take longer for earnings to recover from pandemic-related factors, despite Ecolab’s high levels of service quality and business efficiency.
Finally, we exited the Fund’s out-of-benchmark position in pharmaceutical company Roche, as investors reacted negatively to larger-than-expected declines in sales of some of Roche’s key blockbuster drugs, due to competition from biosimilar treatments. Meanwhile, the pandemic’s impact on clinical-trial activity has limited Roche’s ability to move drug candidates through its pipeline. We also foresaw further challenges from biosimilar competition that could prove difficult for Roche to overcome.
Q What is your outlook heading into the coming fiscal year for the Fund, and how is the outlook reflected in the Fund’s positioning?
A As we look ahead to the remainder of 2021, we believe that the ongoing rollout of COVID-19 vaccinations and the most recent round of economic stimulus from the US government could lead to sharp growth in the US economy during the second half of the calendar year. The yield curve may continue to steepen and, in our view, corporate earnings growth could be strongest for those companies with greater cyclical exposure — or exposure to the ebbs and flows of the economy. The resulting shift in market leadership towards cyclical stocks and away from high-valuation stocks that benefited from historically low interest rates in 2020 could be favorable for the Fund’s holdings. (A yield curve is a line that plots the interest rates, at a set point in time, of bonds having equal credit quality but differing maturity dates.)

10 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 

We believe the Fund’s current holdings are well-suited to benefit from a full reopening of the US and global economies should the vaccine rollouts bring the US and the rest of the world closer to COVID-19 herd immunity. The portfolio currently consists of holdings of what we view as attractively valued, high-quality secular growth stocks, many of which have cyclical economic exposure. By contrast, many of 2020’s strongest performers among high-valuation stocks have already started to underperform in 2021, and we believe owning those more-speculative stocks in the coming year may still present significant downside potential for investors.
Regardless of the macroeconomic backdrop, we have remained committed to investing the Fund in companies that we see as highly profitable and that have strong balance sheets as well as sustainable business models. We seek to hold companies capable of surviving recessions and then emerging with the financial firepower to both invest and thrive during the subsequent recovery.
In sector terms, the Fund remains overweight versus the Russell Index to industrials and financials. Companies in the industrials sector have benefited both from a cyclical economic recovery and from secular growth in industrial automation. Among financials, we have invested the portfolio in what we believe are high-quality firms, which have remained a good fit with our overall approach.
The information technology sector has remained the Fund’s biggest underweight relative to the benchmark heading into the new fiscal year. We continue to have concerns about high valuations and the extreme concentration of the sector within the Russell Index, and have maintained the Fund’s underweight as part of our goal of seeking to manage portfolio risk.
Please refer to the Schedule of Investments on pages 22–25 for a full listing of Fund securities.
All investments are subject to risk, including the possible loss of principal. In the past several years, financial markets have experienced increased volatility and heightened uncertainty. The market prices of securities may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political, or regulatory conditions,

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 11

 

recessions, inflation, changes in interest or currency rates, lack of liquidity in the bond markets, the spread of infectious illness or other public health issues or adverse investor sentiment. These conditions may continue, recur, worsen or spread.
Investing in foreign and/or emerging markets securities involves risks relating to interest rates, currency exchange rates, economic, and political conditions.
The Fund invests in a limited number of securities and, as a result, the Fund’s performance may be more volatile than the performance of other funds holding more securities.
At times, the Fund’s investments may represent industries or industry sectors that are interrelated or have common risks, making the Fund more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors.
These risks may increase share price volatility.
Before investing, consider the product’s investment objectives, risks, charges and expenses. Contact your financial professional or Amundi Asset Management US, Inc., for a prospectus or summary prospectus containing this information. Read it carefully.
Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund’s historical or future performance are statements of opinion as of the date of this report. Past performance is no guarantee of future results.

12 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 

Portfolio Summary | 3/31/21
Sector Distribution
(As a percentage of total investments)*
10 Largest Holdings 
 
(As a percentage of total investments)* 
 
1. 
Alphabet, Inc., Class C 
7.71% 
2. 
Microsoft Corp. 
7.58 
3. 
Amazon.com, Inc. 
6.83 
4. 
Mastercard, Inc. 
4.55 
5. 
QUALCOMM, Inc. 
4.14 
6. 
Stanley Black & Decker, Inc. 
3.75 
7. 
Apple, Inc. 
3.71 
8. 
PayPal Holdings, Inc. 
3.47 
9. 
Booking Holdings, Inc. 
3.39 
10. 
Charles Schwab Corp. 
3.37 
*  Excludes temporary cash investments and all derivative contracts except for options purchased. The Fund is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any securities.
 
Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 13


Prices and Distributions | 3/31/21
Net Asset Value per Share
   
Class 3/31/21 3/31/20 
$31.88 $22.43 
$28.01 $20.07 
$31.94 $22.43 
$31.03 $21.95 
$32.25 $22.63 
 
Distributions per Share: 4/1/20–3/31/21
     
 
Net InvestmentShort-Term Long-Term 
Class IncomeCapital Gains Capital Gains 
$
 —
$0.0024 $2.8231 
$
 —$0.0024 $2.8231 
$
 0.0806$0.0024 $2.8231 
$
 —$0.0024 $2.8231 
$
 0.0500$0.0024 $2.8231 
 
Index Definitions
The Russell 1000 Growth Index is an unmanaged index that measures the performance of large-cap U.S. growth stocks. Index returns assume reinvestment of dividends and, unlike Fund returns, do not reflect any fees, expenses or sales charges. It is not possible to invest directly in an index.
The index defined here pertains to the “Value of $10,000 Investment” and “Value of $5 Million Investment” charts on pages 15–19.
14 Pioneer Fundamental Growth Fund | Annual Report | 3/31/21

 
Performance Update | 3/31/21 
Class A Shares
 
Investment Returns
The mountain chart on the right shows the change in value of a $10,000 investment made in Class A shares of Pioneer Fundamental Growth Fund at public offering price during the periods shown, compared to that of the Russell 1000 Growth Index.

Average Annual Total Returns 
 
(As of March 31, 2021) 
 
 
Net Public Russell 
 
Asset Offering 1000 
 
Value Price Growth 
Period (NAV) (POP) Index 
10 years 
15.13% 
14.45% 
16.63% 
5 years 
17.00 
15.62 
21.05 
1 year 
55.55 
46.61 
62.74 
 
Expense Ratio 
(Per prospectus dated August 1, 2020) 
Gross 
1.07% 
 

Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.
The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.
NAV results represent the percent change in net asset value per share. NAV returns would have been lower had sales charges been reflected. POP returns reflect deduction of maximum 5.75% sales charge. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.
Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.
The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares.
Please refer to the financial highlights for a more current expense ratio.

Pioneer Fundamental Growth Fund | Annual Report | 3/31/21 15

 
Performance Update | 3/31/21 
Class C Shares
 
Investment Returns
The mountain chart on the right shows the change in value of a $10,000 investment made in Class C shares of Pioneer Fundamental Growth Fund during the periods shown, compared to that of the Russell 1000 Growth Index.
Average Annual Total Returns 
 
(As of March 31, 2021) 
 
 
 
 
Russell 
 
 
 
1000 
 
If If Growth 
Period Held Redeemed Index 
10 years 
14.33% 
14.33% 
16.63% 
5 years 
16.22 
16.22 
21.05 
1 year 
54.53 
54.53 
62.74 
 
Expense Ratio 
(Per prospectus dated August 1, 2020) 
Gross 
1.74%