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Pioneer Series Trust X

Filed: 4 Dec 20, 10:26am

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 Pioneer 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 September 30, 2020

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
Semiannual Report | September 30, 2020
     
A: MAFRX C: MCFRX C2: MAUCX K: MAUKX Y: MYFRX 
 
Beginning in or after March 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports like this one will no longer be 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 will be made 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.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications electronically by contacting your financial intermediary or, if you invest directly with the Fund, by calling 1-800-225-6292.
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.amundipioneer.com/us

 

  
Table of Contents 
 
  
  
  
  
  
  
  
  
  
  
  
  
 
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 1


President’s Letter


Dear Shareholders,
The new decade has arrived delivering a calendar year that will go down in the history books. The beginning of 2020 seemed to extend the positive market environment of 2019. Then, March roared in like a lion and the COVID-19 pandemic became a global crisis impacting lives and life as we know it. As the fourth quarter of 2020 got underway, it appeared that the long-anticipated “second wave” of COVID-19 cases was occurring, both in some U.S. states and in Europe. In response, some governments began retightening restrictions on both business and personal activities, likely assuring that the “new normal” conditions created by the pandemic will continue well into 2021.
The long-term impact on the global economy from the COVID-19 virus pandemic, 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, delivering significantly negative performance in the first quarter, and then recovering most of those losses throughout the rest of the spring and summer. Despite the rebound, volatility has remained elevated, with momentum rising and falling on seemingly every bit of positive or negative news regarding potential COVID-19 vaccines as well as headlines surrounding the U.S. elections.
Our business continuity plan was implemented given the new COVID-19 guidelines, and most of our employees are working remotely. 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.
Since 1928, Amundi’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 the first several months of 2020 have 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.
2 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

At Amundi, 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 U.S.
Amundi Pioneer Asset Management USA, Inc.
September 30, 2020

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 | Semiannual Report | 9/30/20 3
 

Portfolio Management Discussion | 9/30/20
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 six-month period ended September 30, 2020. Mr. Roman, a vice president and a portfolio manager at Amundi Pioneer Asset Management, Inc. (Amundi*); Mr. Sharkey, a senior vice president and a portfolio manager at Amundi; Mr. Funderburk, a vice president and a portfolio manager at Amundi; and Mr. Pauwels, a vice president and a portfolio manager at Amundi, are responsible for the day-to-day management of the Fund.
Q How did the Fund perform during the six-month period ended September 30, 2020?
A Pioneer Multi-Asset Ultrashort Income Fund’s Class A shares returned 4.67% at net asset value (NAV) during the six-month period ended September 30, 2020, while the Fund’s benchmark, the ICE Bank of America 3-Month U.S. Dollar LIBOR Index (the ICE BofA Index), returned 0.52%. During the same period, the average return of the 212 mutual funds in Morningstar’s Ultrashort Bond category was 2.88%.
Q Could you describe the market environment for fixed-income investors over the six-month period ended September 30, 2020?
A Entering the period, which began on April 1, 2020, 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 U.S. economy due to COVID-19 necessitated unprecedented monetary and fiscal policy responses. March saw the 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 bolstering investors’ confidence. The measures included reducing the benchmark federal funds target range to near zero and committing to making unlimited purchases of U.S. Treasuries and agency mortgage-backed securities (MBS), as well as providing support for commercial paper issuance, mutual fund liquidity needs, and the issuance of asset-backed securities (ABS). The Fed also enacted brand-new measures with the announcement on March 23 of purchasing programs aimed at supporting both the new-issue and secondary investment-grade corporate bond markets. The end of March also saw the
*  See Notes to Financial Statements Note 7.
4 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

U.S. Congress and the White House agree on a $2.2 trillion stimulus package to help individuals and businesses weather the economic hardships caused by the pandemic.
Investors met the extraordinary support from policy makers in the wake of the pandemic with enthusiasm entering the second quarter of 2020. Market participants sought to put money to work at the now much wider credit spreads in anticipation of receiving fair compensation for taking on the increased 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 progressed, investors became increasingly optimistic that steps toward re-opening the economy would support something resembling a “V-shaped” recovery (a sharp, quick rise). That optimism resulted in a resurgence in investors’ appetite for riskier assets that allowed credit-sensitive areas of the bond market to recover much of their earlier losses over the second quarter, even as rising numbers of COVID-19 cases in a number of states raised concerns.
The relatively benign backdrop carried over into much of the third quarter of 2020 and through the end of the six-month period. However, macroeconomic uncertainty bubbled over during September, weighing on investor sentiment and the performance of riskier assets. The market’s focus on heightened macro risks revolved around three key areas: the status of negotiations in Washington over additional fiscal stimulus from the U.S. government, the trajectory of COVID-19 cases, and the November U.S. elections. With respect to the prospects for a second round of stimulus, a partisan dispute over when to appoint Supreme Court Justice Ginsburg’s replacement further hardened the negotiating positions of both parties and lowered the odds of broad fiscal support coming to fruition prior to the November election. Regarding COVID-19 risks, a notable uptick in European cases of the virus reignited concerns that the U.S. remains at risk for a “second wave” of infections as cooler fall temperatures start to drive people back indoors. Aside from the obvious health and safety concerns of a second wave of COVID-19, there also existed the potential for a new round of economic lockdowns looming on the horizon. Lastly, the November elections not only presented the typical uncertainties over the potential outcome, but also featured concerns about a protracted dispute over the election results.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 5
 

Q Can you review the factors that affected the Fund’s benchmark-relative performance during the six-month period ended September 30, 2020?
A Investments in securitized sectors led the positive contributors to the Fund’s benchmark-relative returns during the six-month period, with allocations to collateralized mortgage obligations (CMOs), ABS, and commercial mortgage-backed securities (CMBS) the top performers. The Fund had an overweight to securitized assets versus its peers over the six-month period.
Within CMOs, the Fund’s exposures to credit-risk-transfer (CRT) securities, which transfer some of the risk of non-payment on residential mortgages from government-sponsored entities to the private sector, had the greatest positive effect on relative performance over the six-month period. The CRT market has continued to benefit from declining forbearance rates and delinquencies, a relatively rapid recovery by the consumer in the wake of COVID-19, strong home sales data, and prepayment rates that could remain very high for the foreseeable future, based on current expectations. Home demand has remained strong and mortgage rates have been at historic lows, which could further support home sales.
Outperformance of the Fund’s CMBS holdings during the six-month period primarily reflected the continued narrowing of spreads. CMBS have continued to gain traction in the market, with buyers encouraged by increased price discovery and improving liquidity. Importantly, with every month that passes showing lower forbearance rates, declining spread duration has been taking place in the sector. (Duration is a measure of the sensitivity of the price, or the value of principal, of a fixed-income investment to a change in interest rates, expressed as a number of years.) The CMBS holdings within the portfolio have represented positions high in the capital structure, with a focus on single-asset, single-borrower exposures. Those positions further break down between single-asset positions, typically a marquis hotel or office property, and single-borrower securities, where any single asset is cross-collateralized by the other properties in the pool, with all assets under common ownership. In the case of a single-asset position, the loan-to-value ratio has typically been very low (often less than 40%), so that even if there is a short-term decline in revenues from the effects of COVID-19, the senior position of the Fund’s holding may protect it against any loss. In addition, sponsors of those structures have tended to be well-capitalized entities who, we believe, would likely lend support in the event of any short-term cash shortfall. For cross-collateralized properties, sponsors may also be inclined to support the structures in order to maintain their ownership position across the assets.
6 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

The Fund’s ABS exposure also contributed positively to relative performance during the six-month period, as that segment of the securitized market has continued to benefit from demand for yield, particularly deeper in the capital structure. Price discovery has continued within the sector in the lower rated tranches, as evidenced by the strong performance of ABS in the “AA” and “BBB” ratings categories. In addition, consumer demand has remained strong, and new car production has yet to catch up with demand, which has benefited the Fund’s sub-prime ABS allocations, as used car prices have remained elevated. Finally, the better-than-expected decline in the unemployment rate to 8.4% in August was good news for more consumer-focused credit sectors, such as ABS and non-agency MBS.
Other sector allocations that had positive effects on the Fund’s benchmark-relative performance during the six-month period included exposures to financials and industrials within corporate credit. The corporate market has benefited from lower levels of new issuance, strong international demand, better-than-expected corporate earnings results, and continued, albeit lower, participation by the Fed with its corporate purchase program. In addition, short-term, high-quality corporate spreads have reverted to near pre-COVID-19 levels.
Additional positive contributors to the Fund’s benchmark-relative performance during the six-month period included allocations to bank loans and collateralized loan obligations (CLOs). The bank-loan market enjoyed narrowing spreads over the period, benefiting from strong CLO demand and the “risk-on” investment environment. Bank loans also benefited from a smaller new-issue calendar and high cash levels resulting from loan paydowns and refinancings, partly due to greater demand for CLOs.
During a six-month period that saw the Fund outperform its benchmark 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 six-month period ended September 30, 2020?
A Throughout the six-month period, we had invested the Fund in floating-rate issues with interest rates tied to either the London Inter-bank Offered Rate (LIBOR) or other short-term reference rates. The decline in
*  Distributions are not guaranteed.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 7
 

LIBOR rates over the period resulted in a decline in the Fund’s distribution yield. Historically, changes to the Fund’s distribution yield have tended to lag changes in LIBOR rates.
Q Did the Fund have any exposure to derivative securities during the six-month period ended September 30, 2020, and did the use of derivatives have an effect on performance?
A No, the Fund had no exposure to derivatives during the period.
Q What is your assessment of the current investment environment in the fixed-income markets?
A The government’s first estimate of the third-quarter U.S. gross domestic product growth rate released after the end of the six-month period showed that domestic economic activity rebounded by more than 30% (annualized) during the quarter. Meanwhile, the economy has recovered more than 75% of the output drawdown recorded during the first half of 2020 while the COVID-19 lockdowns were in full force. Though it seems likely that the U.S. economic growth rate may slow from the third quarter to the fourth, we believe economic activity may continue to expand. History has shown that expansions have tended to be self-sustaining unless derailed by an exogenous shock. While additional fiscal stimulus from the federal government could accelerate the pace of economic activity, we anticipate growth continuing even without the government’s assistance, as personal savings balances have remained above normal. Although an increase in COVID-19 infections seems likely to occur during the winter months, another round of widespread lockdowns may not be necessary given the improvements in patient-treatment methods seen since the virus first arrived in this country.
Our outlook for spread-asset performance has remained positive, and balances out both near-term and medium-term considerations. We appreciate the near-term risks surrounding the uncertainties about the U.S. elections, a potential seasonal increase in COVID-19 infections, and unexpected delays in finding and distributing a safe and effective vaccine for the virus; however, we have framed those risks against asset spreads that, as of quarter-end, generally resided above early-2020 levels. In addition, we believe the medium-term fundamental outlook has remained positive, given continued improvement in COVID-19 treatments, developments regarding the possible approval of a vaccine, and accommodative financial conditions, with the latter currently facing little risk of reversal from tighter monetary policy. Additionally, 12-month forward-looking default forecasts have come down
8 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

from the levels witnessed entering the second quarter of 2020. We have continued to deploy any current pay downs within the Fund at higher spreads (income levels).
Finally, we believe that the options available for the investment of short-term cash have become more limited. Yields on longer-maturity tax-exempt bonds have dropped to record lows as investors have sought stability and incremental yield.
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 21–91 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.
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 by the end of 2021. 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.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 9
 

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.
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.
10 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

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 advisor or Amundi Pioneer Asset Management, 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 | Semiannual Report | 9/30/20 11
 

Portfolio Summary | 9/30/20


Portfolio Diversification

(As a percentage of total investments)*

Amount rounds to less than 0.1%.


10 Largest Holdings

(As a percentage of total investments)*
   
1. 
U.S. Treasury Floating Rate Notes, 0.4% (3 Month U.S. Treasury Bill 
 
 
Money Market Yield + 30 bps), 10/31/21 
2.61% 
2. 
Tidewater Auto Receivables Trust, Series 2020-AA, Class A2, 1.39%, 
 
 
8/15/24 (144A) 
0.69 
3. 
PFS Financing Corp., Series 2019-B, Class A, 0.702% (1 Month USD LIBOR + 
 
 
55 bps), 9/15/23 (144A) 
0.66 
4. 
Verizon Owner Trust, Series 2020-A, Class A1B, 0.426% (1 Month USD LIBOR + 
 
 
27 bps), 7/22/24 
0.59 
5. 
Mitsubishi UFJ Financial Group, Inc., 1.035% (3 Month USD LIBOR + 
 
 
79 bps), 7/25/22 
0.56 
6. 
Truist Bank, 0.87% (3 Month USD LIBOR + 59 bps), 5/17/22 
0.55 
7. 
Federal National Mortgage Association, 0.29% (SOFRRATE + 22 bps), 3/16/22 
0.55 
8. 
U.S. Treasury Floating Rate Notes, 0.32% (3 Month U.S. Treasury Bill Money 
 
 
Market Yield + 22 bps), 7/31/21 
0.55 
9. 
U.S. Treasury Floating Rate Notes, 0.254% (3 Month U.S. Treasury Bill Money 
 
 
Market Yield + 15 bps), 1/31/22 
0.55 
10. 
LSTAR Securities Investment, Ltd., Series 2019-4, Class A1, 1.655% (1 Month 
 
 
USD LIBOR + 150 bps), 5/1/24 (144A) 
0.53 
 
*  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 | Semiannual Report | 9/30/20
 

Prices and Distributions | 9/30/20
Net Asset Value per Share
   
Class 9/30/20 3/31/20 
$9.61 $9.26 
$9.62 $9.26 
C2 
$9.62 $9.27 
$9.64 $9.29 
$9.63 $9.27 
 
Distributions per Share: 4/1/20–9/30/20
    
 
Net Investment Short-Term Long-Term 
Class Income Capital Gains Capital Gains 
$0.0815 $ — $ — 
$0.0670 $ — $ — 
C2 
$0.0675 $ — $ — 
$0.0923 $ — $ — 
$0.0879 $ — $ — 
 
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 | Semiannual Report | 9/30/20 13
 

  
Performance Update | 9/30/20 
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 September 30, 2020) 
 
 
 
ICE BofA 
 
 
 
U.S. 
 
Net Public Dollar 
 
Asset Offering 3-Month
 
Value Price LIBOR 
Period (NAV) (POP)* Index 
Life-of-Class 
 
 
 
(4/29/11) 
1.30% 1.02% 
0.94% 
5 years 
1.36 0.85 
1.50 
1 year 
-1.07 
-1.07 
1.57 
 
Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
 
0.58% 
 
 
 
 
Call 1-800-225-6292 or visit www.amundipioneer.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 | Semiannual Report | 9/30/20
 

  
Performance Update | 9/30/20 
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 September 30, 2020) 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Class 
 
 
(4/29/11) 
0.94% 
0.94% 
5 years 
 1.08 
1.50 
1 year 
-1.18 
1.57 
 
Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.89% 
 
 
 
Call 1-800-225-6292 or visit www.amundipioneer.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 | Semiannual Report | 9/30/20 15
 

  
Performance Update | 9/30/20 
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 September 30, 2020) 
 
 
 
ICE BofA 
 
 
 
U.S. 
 
 
 
Dollar 
 
 
 
3-Month 
 
If If LIBOR 
Period Held Redeemed Index
Life-of-Fund 
 
 
 
(4/29/11) 
0.94% 0.94% 
0.94% 
5 years 
1.10 1.10 
1.50 
1 year 
-1.17 
-1.17 
1.57 
 
Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
 
0.88% 
 
 
 
 
Call 1-800-225-6292 or visit www.amundipioneer.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 | Semiannual Report | 9/30/20
 

  
Performance Update | 9/30/20 
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 September 30, 2020) 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Fund 
 
 
(4/29/11) 
1.51% 
0.94% 
5 years 
 1.63 
1.50 
1 year 
-0.65 
1.57 
 
Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.36% 
 
 
 
Call 1-800-225-6292 or visit www.amundipioneer.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 | Semiannual Report | 9/30/20 17
 

  
Performance Update | 9/30/20 
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 September 30, 2020) 
 
 
ICE BofA 
 
 
U.S. 
 
Net Dollar 
 
Asset 3-Month 
 
Value LIBOR 
Period (NAV) Index 
Life-of-Class 
 
 
(4/29/11) 
1.48% 
0.94% 
5 years 
 1.55 
1.50 
1 year 
-0.83 
1.57 
 
Expense Ratio 
 
 
(Per prospectus dated August 1, 2020) 
Gross 
 
 
0.44% 
 
 
 
Call 1-800-225-6292 or visit www.amundipioneer.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 | Semiannual Report | 9/30/20
 

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 April 1, 2020 through September 30, 2020.
      
Share Class C2 
Beginning Account 
$1,000.00 $1,000.00 $1,000.00 $1,000.00 $1,000.00 
Value on 4/1/20 
 
 
 
 
 
Ending Account Value 
$1,046.70 $1,046.20 $1,045.20 $1,047.80 $1,048.50 
(after expenses) 
 
 
 
 
 
on 9/30/20 
 
 
 
 
 
Expenses Paid 
$3.03 $4.62 $4.72 $1.90 $2.26 
During Period* 
 
 
 
 
 
 
*  Expenses are equal to the Fund’s annualized expense ratio of 0.59%, 0.90%, 0.92%, 0.37% and 0.44% for class A, C, C2, K, and Y respectively, multiplied by the average account value over the period, multiplied by 183/365 (to reflect the partial year period).
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 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 April 1, 2020 through September 30, 2020.
      
Share Class C2 
Beginning Account 
$1,000.00 $1,000.00 $1,000.00 $1,000.00 $1,000.00 
Value on 4/1/20 
 
 
 
 
 
Ending Account Value 
$1,022.11 $1,020.56 $1,020.46 $1,023.21 $1,022.86 
(after expenses) 
 
 
 
 
 
on 9/30/20 
 
 
 
 
 
Expenses Paid 
$2.99 $4.56 $4.66 $1.88 $2.23 
During Period* 
 
 
 
 
 
 
*  Expenses are equal to the Fund’s annualized expense ratio of 0.59%, 0.90%, 0.92%, 0.37% and 0.44% for class A, C, C2, K, and Y respectively, multiplied by the average account value over the period, multiplied by 183/365 (to reflect the partial year period).
20 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

Schedule of Investments | 9/30/20 (unaudited)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 UNAFFILIATED ISSUERS — 100.5% 
 

 ASSET BACKED SECURITIES — 32.9% 
 
 of Net Assets 
 
202,372(a)  
321 Henderson Receivables I LLC, Series 2004-A, 
 
 
 
Class A1, 0.502% (1 Month USD LIBOR + 
 
 
 
35 bps), 9/15/45 (144A) 
$ 197,864 
285,989(a)  
321 Henderson Receivables I LLC, Series 2006-1A, 
 
 
 
Class A1, 0.352% (1 Month USD LIBOR + 
 
 
 
20 bps), 3/15/41 (144A) 
281,358 
796,435(a)  
321 Henderson Receivables I LLC, Series 2006-2A, 
 
 
 
Class A1, 0.352% (1 Month USD LIBOR + 
 
 
 
20 bps), 6/15/41 (144A) 
770,189 
1,148,793(a)  
321 Henderson Receivables I LLC, Series 2006-3A, 
 
 
 
Class A1, 0.352% (1 Month USD LIBOR + 
 
 
 
20 bps), 9/15/41 (144A) 
1,108,815 
1,002,419(a)  
321 Henderson Receivables I LLC, Series 2006-4A, 
 
 
 
Class A1, 0.352% (1 Month USD LIBOR + 
 
 
 
20 bps), 12/15/41 (144A) 
990,808 
351,422(a)  
321 Henderson Receivables I LLC, Series 2007-1A, 
 
 
 
Class A1, 0.352% (1 Month USD LIBOR + 
 
 
 
20 bps), 3/15/42 (144A) 
331,873 
1,874,071(a)  
321 Henderson Receivables LLC, Series 2005-1A, 
 
 
 
Class A1, 0.382% (1 Month USD LIBOR + 23 bps), 
 
 
 
11/15/40 (144A) 
1,806,380 
552,857(a)  
522 Funding Clo I, Ltd., Series 2018-3A, Class X, 0.972% 
 
 
 
(3 Month USD LIBOR + 70 bps), 10/20/31 (144A) 
552,869 
1,460,330(a)  
ABFC Trust, Series 2004-OPT2, Class M1, 0.973% 
 
 
 
(1 Month USD LIBOR + 83 bps), 8/25/33 
1,449,762 
202,410(a)  
ABFC Trust, Series 2005-WMC1, Class M2, 0.823% 
 
 
 
(1 Month USD LIBOR + 68 bps), 6/25/35 
204,263 
5,216,151  
ACC Trust, Series 2019-2, Class A, 2.82%, 
 
 
 
2/21/23 (144A) 
5,247,190 
503,135(a)  
ACE Securities Corp. Home Equity Loan Trust, Series 
 
 
 
2005-WF1, Class M2, 0.808% (1 Month USD LIBOR + 
 
 
 
66 bps), 5/25/35 
512,084 
1,703,260(a)  
ACIS CLO, Ltd., Series 2015-6A, Class A1, 1.841% 
 
 
 
(3 Month USD LIBOR + 159 bps), 5/1/27 (144A) 
1,701,543 
2,250,366(a)  
Aegis Asset Backed Securities Trust Mortgage 
 
 
 
Pass-Through Ctfs, Series 2004-4, Class M1, 1.048% 
 
 
 
(1 Month USD LIBOR + 90 bps), 10/25/34 
2,223,830 
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) 
7,100,000 
135,002(a)  
Allegro CLO I, Ltd., Series 2013-1A, Class A2R, 1.918% 
 
 
 
(3 Month USD LIBOR + 165 bps), 1/30/26 (144A) 
134,913 
8,000,000  
American Credit Acceptance Receivables Trust, Series 
 
 
 
2020-1, Class B, 2.08%, 12/13/23 (144A) 
8,078,283 
4,188,345  
American Credit Acceptance Receivables Trust, Series 
 
 
 
2020-2, Class A, 1.65%, 12/13/23 (144A) 
4,218,617 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 21
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
56,762(a)  Amortizing Residential Collateral Trust, Series 
 
 
 2002-BC5, Class M1, 1.183% (1 Month USD LIBOR + 
 
 
 104 bps), 7/25/32 $ 56,554 
3,877,187  Amur Equipment Finance Receivables V LLC, Series 
 
 
 2018-1A, Class A2, 3.24%, 12/20/23 (144A) 3,906,100 
4,917,245  Amur Equipment Finance Receivables VI LLC, Series 
 
 
 2018-2A, Class A2, 3.89%, 7/20/22 (144A) 5,000,866 
4,000,000  Amur Equipment Finance Receivables VII LLC, Series 
 
 
 2019-1A, Class B, 2.8%, 3/20/25 (144A) 4,022,605 
206,250(a)  Annisa CLO, Ltd., Series 2016-2A, Class X, 0.872% 
 
 
 (3 Month USD LIBOR + 60 bps), 7/20/31 (144A) 206,248 
321,429(a)  Apidos CLO XXIX, Series 2018-29A, Class X, 0.795% 
 
 
 (3 Month USD LIBOR + 55 bps), 7/25/30 (144A) 321,428 
2,600,000(a)  Apidos CLO XXXII, Series 2019-32A, Class X, 0.922% 
 
 
 (3 Month USD LIBOR + 65 bps), 1/20/33 (144A) 2,599,997 
3,067,288(a)  Apres Static CLO, Ltd., Series 2019-1A, Class A1, 
 
 
 
1.445% (3 Month USD LIBOR + 117 bps), 1/15/27 (144A) 
3,059,120 
11,419,857  Aqua Finance Trust, Series 2019-A, Class A, 3.14%, 
 
 
 7/16/40 (144A) 11,689,244 
10,000,000  Aqua Finance Trust, Series 2020-AA, Class A, 1.9%, 
 
 
 7/17/46 (144A) 10,036,596 
848,794(a)  Argent Securities, Inc. Asset-Backed Pass-Through 
 

 
Certificates, Series 2004-W11, Class M2, 1.198%
 
 
 (1 Month USD LIBOR + 105 bps), 11/25/34 849,853 
70,930(a)  Argent Securities, Inc. Asset-Backed Pass-Through 
 

 
Certificates, Series 2005-W3, Class A2D, 0.488%
 
 
 (1 Month USD LIBOR + 34 bps), 11/25/35 70,716 
6,552,470  Arivo Acceptance Auto Loan Receivables Trust, Series 
 
 
 2019-1, Class A, 2.99%, 7/15/24 (144A) 6,663,814 
19,651,783  Ascentium Equipment Receivables, Series 2019-2A, 
 
 
 Class A2, 2.24%, 6/10/22 (144A) 19,801,828 
122,779(a)  Asset Backed Securities Corp. Home Equity Loan 
 
 
 Trust, Series 2005-HE4, Class M4, 1.093% (1 Month 
 
 
 USD LIBOR + 95 bps), 5/25/35 122,778 
14,817(a)  Asset-Backed Pass-Through Certificates, Series 
 
 
 2004-R2, Class A1A, 0.838% (1 Month USD LIBOR + 
 
 
 69 bps), 4/25/34 14,787 
156,004(a)  Asset-Backed Pass-Through Certificates, Series 
 
 
 2004-R2, Class A1B, 0.768% (1 Month USD LIBOR + 
 
 
 62 bps), 4/25/34 155,693 
14,095,111(a)  Atlas Senior Loan Fund III, Ltd., Series 2013-1A, 
 
 
 Class AR, 1.11% (3 Month USD LIBOR + 
 
 
 83 bps), 11/17/27 (144A) 13,898,724 
745,791(a)  Atlas Senior Loan Fund XII, Ltd., Series 2018-12A, 
 
 
 Class X, 1.014% (3 Month USD LIBOR + 
 
 
 75 bps), 10/24/31 (144A) 745,765 
697,037  Avant Loans Funding Trust, Series 2019-A, Class A, 
 
 
 3.48%, 7/15/22 (144A) 697,797 
 
The accompanying notes are an integral part of these financial statements.
22 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,919,418  
Avant Loans Funding Trust, Series 2019-B, Class A, 
 
 
 
2.72%, 10/15/26 (144A) 
$ 2,930,673 
290,009  
Avid Automobile Receivables Trust, Series 2018-1, 
 
 
 
Class A, 2.84%, 8/15/23 (144A) 
290,449 
4,672,074  
Avid Automobile Receivables Trust, Series 2019-1, 
 
 
 
Class A, 2.62%, 2/15/24 (144A) 
4,720,688 
633,333(a)  
Babson CLO, Ltd., Series 2015-IA, Class XR, 0.822% 
 
 
 
(3 Month USD LIBOR + 55 bps), 1/20/31 (144A) 
633,330 
50,000(a)  
Barings CLO, Ltd., Series 2018-2A, Class X, 0.875% 
 
 
 
(3 Month USD LIBOR + 60 bps), 4/15/30 (144A) 
50,000 
833,332(a)  
Barings CLO, Ltd., Series 2019-1A, Class X, 1.025% 
 
 
 
(3 Month USD LIBOR + 75 bps), 4/15/31 (144A) 
833,331 
6,250,000(a)  
Barings Middle Market CLO, Ltd., Series 2018-IA, 
 
 
 
Class A1, 1.805% (3 Month USD LIBOR + 
 
 
 
153 bps), 1/15/31 (144A) 
6,086,244 
1,125,000(a)  
Battery Park CLO, Ltd., Series 2019-1A, Class X, 0.925% 
 
 
 
(3 Month USD LIBOR + 65 bps), 7/15/32 (144A) 
1,124,999 
2,375,324  
BCC Funding XIV LLC, Series 2018-1A, Class A2, 2.96%, 
 
 
 
6/20/23 (144A) 
2,384,205 
2,500,000(a)  
BDS, Ltd., Series 2020-FL5, Class C, 2.2% (1 Month USD 
 
 
 
LIBOR + 205 bps), 2/16/37 (144A) 
2,427,742 
1,203,125(a)  
Bean Creek CLO, Ltd., Series 2015-1A, Class XR, 0.872% 
 
 
 
(3 Month USD LIBOR + 60 bps), 4/20/31 (144A) 
1,203,102 
70,823(a)  
Bear Stearns Asset Backed Securities I Trust, Series 
 
 
 
2005-TC1, Class M1, 0.808% (1 Month USD LIBOR 
 
 
 
+ 66 bps), 5/25/35 
70,790 
314,525(a)  
Bear Stearns Asset Backed Securities Trust, Series 
 
 
 
2001-3, Class A1, 1.048% (1 Month USD LIBOR + 
 
 
 
90 bps), 10/27/32 
308,675 
391,248(a)  
BlueMountain CLO, Ltd., Series 2013-2A, Class X, 0.908% 
 
 
 
(3 Month USD LIBOR + 65 bps), 10/22/30 (144A) 
391,238 
252,517(a)  
BlueMountain CLO, Ltd., Series 2018-2A, Class X, 0.93% 
 
 
 
(3 Month USD LIBOR + 65 bps), 8/15/31 (144A) 
252,510 
2,250,000(a)  
California Street CLO IX LP, Series 2012-9A, Class XR2, 
 
 
 
0.971% (3 Month USD LIBOR + 70 bps), 7/16/32 (144A) 
2,249,858 
508,962(a)  
Carlyle US CLO, Ltd., Series 2019-4A, Class M, 0.925% 
 
 
 
(3 Month USD LIBOR + 65 bps), 1/15/33 (144A) 
508,912 
7,513,901  
Carnow Auto Receivables Trust, Series 2019-1A, 
 
 
 
Class A, 2.72%, 11/15/22 (144A) 
7,570,566 
1,564,570  
Carvana Auto Receivables Trust, Series 2019-4A, 
 
 
 
Class A2, 2.2%, 7/15/22 (144A) 
1,571,018 
8,000,000  
Carvana Auto Receivables Trust, Series 2020-N1A, 
 
 
 
Class B, 2.01%, 3/17/25 (144A) 
8,163,799 
5,000,000  
Carvana Auto Receivables Trust, Series 2020-N1A, 
 
 
 
Class D, 3.43%, 1/15/26 (144A) 
5,188,816 
627,089  
Cazenovia Creek Funding II LLC, Series 2018-1A, 
 
 
 
Class B, 3.984%, 7/15/30 (144A) 
623,371 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 23
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
5,000,000(a)  
CBAM, Ltd., Series 2017-3A, Class A, 1.503% 
 
 
 
(3 Month USD LIBOR + 123 bps), 10/17/29 (144A) 
$ 4,975,385 
687,500(a)  
Cent CLO 21, Ltd., Series 2014-21A, Class XR2, 
 
 
 
0.895% (3 Month USD LIBOR + 65 bps), 
 
 
 
7/27/30 (144A) 
687,499 
29,619(b)  
Centex Home Equity Loan Trust, Series 2003-A, 
 
 
 
Class AF6, 3.654%, 3/25/33 
29,676 
1,500,000(a)  
Cerberus Loan Funding XXVIII LP, Series 2020-1A, 
 
 
 
Class A, 0.0% (3 Month USD LIBOR + 
 
 
 
185 bps), 10/15/31 (144A) 
1,500,000 
93,750(a)  
CFIP CLO, Ltd., Series 2018-1A, Class X, 1.022% 
 
 
 
(3 Month USD LIBOR + 75 bps), 7/18/31 (144A) 
93,750 
4,699,013(b)  
CFMT LLC, Series 2020-HB3, Class A, 2.812%, 5/25/30 
 
 
 
(144A) 
4,739,458 
5,750,000  
Chase Auto Credit Linked Notes, Series 2020-1, Class B, 
 
 
 
0.991%, 1/25/28 (144A) 
5,758,470 
304,323  
Chesapeake Funding II LLC, Series 2017-2A, Class A1, 
 
 
 
1.99%, 5/15/29 (144A) 
305,067 
666,467(a)  
Chesapeake Funding II LLC, Series 2017-2A, Class A2, 
 
 
 
0.602% (1 Month USD LIBOR + 45 bps), 5/15/29 
 
 
 
(144A) 
666,427 
1,352,096(a)  
Chesapeake Funding II LLC, Series 2017-3A, Class A2, 
 
 
 
0.492% (1 Month USD LIBOR + 34 bps), 8/15/29 
 
 
 
(144A) 
1,351,360 
2,794,743(a)  
Chesapeake Funding II LLC, Series 2018-1A, Class A2, 
 
 
 
0.602% (1 Month USD LIBOR + 45 bps), 4/15/30 
 
 
 
(144A) 
2,801,511 
16,315,000(a)  
CIFC Funding Ltd., Series 2015-3A, Class AR, 1.142% 
 
 
 
(3 Month USD LIBOR + 87 bps), 4/19/29 (144A) 
16,121,227 
714,286(a)  
CIFC Funding, Ltd., Series 2014-4RA, Class X, 0.823% 
 
 
 
(3 Month USD LIBOR + 55 bps), 10/17/30 (144A) 
714,285 
4,711,523  
CIG Auto Receivables Trust, Series 2019-1A, Class A, 
 
 
 
3.33%, 8/15/24 (144A) 
4,767,363 
3,200,000  
CIG Auto Receivables Trust, Series 2020-1A, Class A, 
 
 
 
0.68%, 10/12/23 (144A) 
3,200,303 
2,375,342(a)  
CIM Small Business Loan Trust, Series 2018-1A, 
 
 
 
Class A, 1.558% (1 Month USD LIBOR + 140 bps), 
 
 
 
3/20/43 (144A) 
2,324,183 
10,000,000(a)  
Citibank Credit Card Issuance Trust, Series 2017-A7, 
 
 
 
Class A7, 0.524% (1 Month USD LIBOR + 
 
 
 
37 bps), 8/8/24 
10,037,606 
1,178,291(a)  
Citigroup Mortgage Loan Trust, Inc., Series 2006-WFH1, 
 
 
 
Class M3, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 1/25/36 
1,176,951 
312,500(a)  
Clear Creek CLO, Series 2015-1A, Class X, 1.272% 
 
 
 
(3 Month USD LIBOR + 100 bps), 10/20/30 (144A) 
312,492 
3,250,000(a)  
Cole Park CLO, Ltd., Series 2015-1A, Class AR, 1.322% 
 
 
 
(3 Month USD LIBOR + 105 bps), 10/20/28 (144A) 
3,232,469 
 
The accompanying notes are an integral part of these financial statements.
24 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
875,000(a)  
Columbia Cent CLO 28, Ltd., Series 2018-28A, Class X, 
 
  
0.892% (3 Month USD LIBOR + 65 bps), 
 
  
11/7/30 (144A) 
$ 874,998 
1,347,777  
Commonbond Student Loan Trust, Series 2016-B, 
 
  
Class A1, 2.73%, 10/25/40 (144A) 
1,367,382 
201,398(a)  
Commonbond Student Loan Trust, Series 2016-B, 
 
  
Class A2, 1.598% (1 Month USD LIBOR + 145 bps), 
 
  
10/25/40 (144A) 
201,795 
1,849,523(a)  
Commonbond Student Loan Trust, Series 2017-AGS, 
 
  
Class A2, 0.998% (1 Month USD LIBOR + 
 
  
85 bps), 5/25/41 (144A) 
1,839,171 
3,548,309(a)  
Commonbond Student Loan Trust, Series 2017-BGS, 
 
  
Class A2, 0.798% (1 Month USD LIBOR + 
 
  
65 bps), 9/25/42 (144A) 
3,524,636 
2,890,916(a)  
Commonbond Student Loan Trust, Series 2018-AGS, 
 
  
Class A2, 0.648% (1 Month USD LIBOR + 
 
  
50 bps), 2/25/44 (144A) 
2,847,554 
5,891,004(a)  
Commonbond Student Loan Trust, Series 2018-BGS, 
 
  
Class A2, 0.718% (1 Month USD LIBOR + 
 
  
57 bps), 9/25/45 (144A) 
5,819,258 
4,196,638(a)  
Commonbond Student Loan Trust, Series 2018-CGS, 
 
  
Class A2, 0.948% (1 Month USD LIBOR + 
 
  
80 bps), 2/25/46 (144A) 
4,152,102 
7,294,106(a)  
Commonbond Student Loan Trust, Series 2019-AGS, 
 
  
Class A2, 1.048% (1 Month USD LIBOR + 
 
  
90 bps), 1/25/47 (144A) 
7,273,866 
99,333  
Conn’s Receivables Funding LLC, Series 2018-A, 
 
  
Class A, 3.25%, 1/15/23 (144A) 
99,357 
157,606  
Conn’s Receivables Funding LLC, Series 2018-A, 
 
  
Class B, 4.65%, 1/15/23 (144A) 
157,497 
995,319  
Conn’s Receivables Funding LLC, Series 2019-A, 
 
  
Class A, 3.4%, 10/16/23 (144A) 
997,226 
3,110,529  
Conn’s Receivables Funding LLC, Series 2019-A, 
 
  
Class B, 4.36%, 10/16/23 (144A) 
3,111,002 
3,334,388  
Conn’s Receivables Funding LLC, Series 2019-B, 
 
  
Class A, 2.66%, 6/17/24 (144A) 
3,333,389 
80,945(a)  
Conseco Finance Home Equity Loan Trust, Series 
 
  
2002-C, Class MV1, 1.652% (1 Month USD LIBOR + 
 
  
150 bps), 5/15/32 
80,754 
1,753,939  
Consumer Lending Receivables Trust, Series 2019-A, 
 
  
Class A, 3.52%, 4/15/26 (144A) 
1,757,145 
17,880,392  
Consumer Loan Underlying Bond Club Certificate 
 

 
Issuer Trust, Series 2019-HP1, Class A, 2.59%,
 
  
12/15/26 (144A) 
18,083,196 
6,437,763  
Consumer Loan Underlying Bond CLUB Credit Trust, 
 
  
Series 2020-P1, Class A, 2.26%, 3/15/28 (144A) 
6,486,436 
531,539  
Consumer Loan Underlying Bond Credit Trust, Series 
 
  
2018-P2, Class A, 3.47%, 10/15/25 (144A) 
532,659 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 25
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,268,594  
Consumer Loan Underlying Bond Credit Trust, Series 
 
 
 
2019-P1, Class A, 2.94%, 7/15/26 (144A) 
$ 2,285,685 
82,288(a)  
Countrywide Asset-Backed Certificates, Series 2005-9, 
 
 
 
Class M1, 0.668% (1 Month USD LIBOR + 
 
 
 
52 bps), 1/25/36 
82,215 
87,498(a)  
Countrywide Asset-Backed Certificates, Series 2006-3, 
 
 
 
Class 2A3, 0.438% (1 Month USD LIBOR + 
 
 
 
29 bps), 6/25/36 
87,420 
2,792,309(a)  
Countrywide Asset-Backed Certificates, Series 2006-4, 
 
 
 
Class 2A3, 0.438% (1 Month USD LIBOR + 
 
 
 
29 bps), 7/25/36 
2,784,834 
5,000,000  
Credit Acceptance Auto Loan Trust, Series 2020-1A, 
 
 
 
Class C, 2.59%, 6/15/29 (144A) 
5,063,265 
1,020,919(a)  
Credit Suisse Seasoned Loan Trust, Series 2006-1, 
 
 
 
Class A, 0.388% (1 Month USD LIBOR + 
 
 
 
24 bps), 10/25/34 (144A) 
1,020,055 
57,526(a)  
Credit-Based Asset Servicing & Securitization LLC, 
 
 
 
Series 2005-CB3, Class M2, 1.078% (1 Month USD 
 
 
 
LIBOR + 93 bps), 6/25/35 
57,526 
294,348(a)  
CSFB Mortgage-Backed Pass-Through Certificates, 
 
 
 
Series 2005-AGE1, Class M3, 0.798% (1 Month USD 
 
 
 
LIBOR + 65 bps), 2/25/32 
294,241 
46,662(a)  
CWABS Asset-Backed Certificates Trust, Series 
 
 
 
2005-17, Class 3AV2, 0.488% (1 Month USD LIBOR + 
 
 
 
34 bps), 5/25/36 
46,606 
335,982(a)  
CWABS Asset-Backed Certificates Trust, Series 
 
 
 
2005-AB1, Class M1, 0.778% (1 Month USD LIBOR + 
 
 
 
63 bps), 8/25/35 
335,637 
1,612,232(a)  
CWHEQ Revolving Home Equity Loan Resuritization 
 
 
 
Trust, Series 2006-RES, Class 4M1A, 0.432% (1 Month 
 
 
 
USD LIBOR + 28 bps), 2/15/34 (144A) 
1,581,218 
2,314,925(a)  
CWHEQ Revolving Home Equity Loan Resuritization 
 
 
 
Trust, Series 2006-RES, Class 4N1A, 0.432% (1 Month 
 
 
 
USD LIBOR + 28 bps), 2/15/34 (144A) 
2,257,045 
157,636  
Dell Equipment Finance Trust, Series 2018-2, Class A3, 
 
 
 
3.37%, 10/22/23 (144A) 
159,165 
3,781,738  
Dell Equipment Finance Trust, Series 2020-1, Class A1, 
 
 
 
1.983%, 5/21/21 (144A) 
3,794,234 
2,000,000  
Dell Equipment Finance Trust, Series 2020-1, Class A2, 
 
 
 
2.26%, 6/22/22 (144A) 
2,032,948 
120  
Delta Funding Home Equity Loan Trust, Series 1997-2, 
 
 
 
Class A6, 7.04%, 6/25/27 
114 
3,189,734  
Diamond Resorts Owner Trust, Series 2016-1, Class B, 
 
 
 
3.37%, 11/20/28 (144A) 
3,188,618 
5,927,945  
DLL LLC, Series 2018-ST2, Class A3, 3.46%, 
 
 
 
1/20/22 (144A) 
5,980,173 
448,336(a)  
DRB Prime Student Loan Trust, Series 2015-D, 
 
 
 
Class A1, 1.848% (1 Month USD LIBOR + 170 bps), 
 
 
 
1/25/40 (144A) 
449,731 
 
The accompanying notes are an integral part of these financial statements.
26 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
227,914(a)  
DRB Prime Student Loan Trust, Series 2016-B, 
 
 
 
Class A1, 1.948% (1 Month USD LIBOR + 180 bps), 
 
 
 
6/25/40 (144A) 
$ 229,531 
85,227  
DRB Prime Student Loan Trust, Series 2016-B, 
 
 
 
Class A3, 2.23%, 6/25/36 (144A) 
85,369 
1,337,348(a)  
DRB Prime Student Loan Trust, Series 2017-A, 
 
 
 
Class A1, 0.998% (1 Month USD LIBOR + 85 bps), 
 
 
 
5/27/42 (144A) 
1,335,910 
1,991,674  
Drive Auto Receivables Trust, Series 2020-2, Class A2A, 
 
 
 
0.85%, 7/17/23 
1,995,114 
1,903,687(a)  
Drug Royalty III LP 1, Series 2017-1A, Class A1, 2.775% 
 
 
 
(3 Month USD LIBOR + 250 bps), 4/15/27 (144A) 
1,902,370 
1,883,304(a)  
Drug Royalty III LP 1, Series 2018-1A, Class A1, 1.875% 
 
 
 
(3 Month USD LIBOR + 160 bps), 10/15/31 (144A) 
1,853,474 
1,499,540(a)  
Dryden 33 Senior Loan Fund, Series 2014-33A, 
 
 
 
Class AR2, 1.505% (3 Month USD LIBOR + 123 bps), 
 
 
 
4/15/29 (144A) 
1,493,921 
1,406,250(a)  
Dryden 80 CLO, Ltd., Series 2019-80A, Class X, 1.173% 
 
 
 
(3 Month USD LIBOR + 90 bps), 1/17/33 (144A) 
1,406,247 
5,589,974  
DT Auto Owner Trust, Series 2020-1A, Class A, 1.94%, 
 
 
 
9/15/23 (144A) 
5,624,897 
253,365(a)  
Earnest Student Loan Program LLC, Series 2016-C, 
 
 
 
Class A1, 1.998% (1 Month USD LIBOR + 
 
 
 
185 bps), 10/27/36 (144A) 
254,273 
236,244(a)  
Earnest Student Loan Program LLC, Series 2016-D, 
 
 
 
Class A1, 1.548% (1 Month USD LIBOR + 
 
 
 
140 bps), 1/25/41 (144A) 
236,779 
800,082(a)  
Earnest Student Loan Program LLC, Series 2017-A, 
 
 
 
Class A1, 1.148% (1 Month USD LIBOR + 
 
 
 
100 bps), 1/25/41 (144A) 
799,539 
15,950,000(a)  
Elevation CLO, Ltd., Series 2015-4A, Class CR, 2.472% 
 
 
 
(3 Month USD LIBOR + 220 bps), 4/18/27 (144A) 
15,809,959 
2,000,000(a)  
Elm CLO, Ltd., Series 2014-1A, Class BRR, 2.023% 
 
 
 
(3 Month USD LIBOR + 175 bps), 1/17/29 (144A) 
1,984,046 
2,000,000(a)  
Elmwood CLO IV, Ltd., Series 2020-1A, Class X, 
 
 
 
1.882% (3 Month USD LIBOR + 70 bps), 4/15/33 (144A) 
1,973,170 
1,000,000(a)  
Evergreen Credit Card Trust, Series 2019-1, Class A, 
 
 
 
0.632% (1 Month USD LIBOR + 48 bps), 1/15/23 
 
 
 
(144A) 
1,001,099 
1,904,365  
FCI Funding LLC, Series 2019-1A, Class A, 3.63%, 
 
 
 
2/18/31 (144A) 
1,937,634 
12,015,791  
FHF Trust, Series 2020-1A, Class A, 2.59%, 12/15/23 
 
 
 
(144A) 
12,066,699 
16,915,943(b)  
Finance of America HECM Buyout, Series 2020-HB1, 
 
 
 
Class A, 2.012%, 2/25/30 (144A) 
17,024,171 
35,149(a)  
First Franklin Mortgage Loan Trust, Series 2004-FF4, 
 
 
 
Class M1, 1.003% (1 Month USD LIBOR + 
 
 
 
86 bps), 6/25/34 
35,050 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 27
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
128,019(a)  
First Franklin Mortgage Loan Trust, Series 2005-FFH2, 
 
  
Class M2, 0.958% (1 Month USD LIBOR + 
 
  
81 bps), 4/25/35 (144A) 
$ 127,993 
2,534,882  
First Investors Auto Owner Trust, Series 2019-1A, 
 
  
Class A, 2.89%, 3/15/24 (144A) 
2,567,086 
20,033,423  
First Investors Auto Owner Trust, Series 2020-1A, 
 
  
Class A, 1.49%, 1/15/25 (144A) 
20,201,802 
6,510,000  
First Investors Auto Owner Trust, Series 2020-1A, 
 
  
Class B, 1.85%, 2/17/26 (144A) 
6,648,870 
9,000,000(a)  
First National Master Note Trust, Series 2017-2, 
 
  
Class A, 0.592% (1 Month USD LIBOR + 
 
  
44 bps), 10/16/23 
8,999,845 
2,000,000  
Ford Credit Auto Owner Trust, Series 2016-2, Class A, 
 
  
2.03%, 12/15/27 (144A) 
2,023,121 
12,975,000(a)  
Fort CRE LLC, Series 2018-1A, Class A1, 1.502% 
 
  
(1 Month USD LIBOR + 135 bps), 11/16/35 (144A) 
12,713,556 
500,000(a)  
Fort Washington CLO, Series 2019-1A, Class A, 1.692% 
 
  
(3 Month USD LIBOR + 142 bps), 10/20/32 (144A) 
489,526 
3,600,000(a)  
Fortress Credit Opportunities IX CLO, Ltd., Series 
 
  
2017-9A, Class A1T, 1.83% (3 Month USD LIBOR + 
 
  
155 bps), 11/15/29 (144A) 
3,576,622 
3,000,000(a)  
Fortress Credit Opportunities IX CLO, Ltd., Series 
 
  
2020-13A, Class A, 2.518% (3 Month USD LIBOR + 
 
  
225 bps), 7/15/28 (144A) 
3,000,891 
2,750,000(a)  
Fortress Credit Opportunities VI CLO, Ltd., Series 
 
  
2015-6A, Class A1TR, 1.633% (3 Month USD LIBOR + 
 
  
136 bps), 7/10/30 (144A) 
2,667,987 
2,924,447  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2019-1, Class A2, 2.58%, 3/15/23 (144A) 
2,943,514 
5,939,030  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2020-1, Class A2, 1.97%, 9/15/23 (144A) 
5,989,154 
2,500,000  
Foursight Capital Automobile Receivables Trust, Series 
 
  
2020-1, Class B, 2.27%, 2/18/25 (144A) 
2,570,460 
3,584,692  
Freed ABS Trust, Series 2020-2CP, Class A, 4.52%, 
 
  
6/18/27 (144A) 
3,628,374 
4,883,220  
Freed ABS Trust, Series 2020-FP1, Class A, 2.52%, 
 
  
3/18/27 (144A) 
4,885,174 
1,835,494(a)  
Fremont Home Loan Trust, Series 2005-E, Class 1A1, 
 
  
0.378% (1 Month USD LIBOR + 23 bps), 1/25/36 
1,829,799 
4,892,125(a)  
Fremont Home Loan Trust, Series 2006-2, Class 1A1, 
 
  
0.308% (1 Month USD LIBOR + 16 bps), 2/25/36 
4,840,698 
6,647,615  
Genesis Private Label Amortizing Trust, Series 2020-1, 
 
  
Class A, 2.08%, 7/20/30 (144A) 
6,655,685 
411,540(a)  
GE-WMC Asset-Backed Pass-Through Certificates, 
 
  
Series 2005-2, Class A1, 0.598% (1 Month USD LIBOR + 
 
  
45 bps), 12/25/35 
411,553 
1,588,749  
GLS Auto Receivables Issuer Trust, Series 2019-1A, 
 
  
Class A, 3.37%, 1/17/23 (144A) 
1,599,589 
 
The accompanying notes are an integral part of these financial statements.
28 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
5,162,780  
GLS Auto Receivables Issuer Trust, Series 2019-3A, 
 
  
Class A, 2.58%, 7/17/23 (144A) 
$ 5,213,511 
3,000,000  
GLS Auto Receivables Issuer Trust, Series 2019-3A, 
 
  
Class B, 2.72%, 6/17/24 (144A) 
3,072,379 
5,182,030  
GLS Auto Receivables Issuer Trust, Series 2019-4A, 
 
  
Class A, 2.47%, 11/15/23 (144A) 
5,244,758 
5,231,408  
GLS Auto Receivables Issuer Trust, Series 2020-2A, 
 
  
Class A, 1.58%, 8/15/24 (144A) 
5,281,743 
800,000  
GLS Auto Receivables Trust, Series 2018-1A, Class B, 
 
  
3.52%, 8/15/23 (144A) 
812,423 
595,756  
GLS Auto Receivables Trust, Series 2018-3A, Class A, 
 
  
3.35%, 8/15/22 (144A) 
597,078 
3,800,318(a)  
GM Financial Automobile Leasing Trust, Series 2019-3, 
 
  
Class A2B, 0.426% (1 Month USD LIBOR + 
 
  
27 bps), 10/20/21 
3,801,276 
2,756,992  
Gold Key Resorts LLC, Series 2014-A, Class B, 3.72%, 
 
  
3/17/31 (144A) 
2,771,066 
312,500(a)  
Goldentree Loan Management US CLO 3, Ltd., Series 
 
  
2018-3A, Class X, 0.822% (3 Month USD LIBOR + 
 
  
55 bps), 4/20/30 (144A) 
312,500 
933,333(a)  
Goldentree Loan Management US CLO 5, Ltd., Series 
 
  
2019-5A, Class X, 0.772% (3 Month USD LIBOR + 
 
  
50 bps), 10/20/32 (144A) 
933,332 
700,000(a)  
Goldentree Loan Management US Clo 8 Ltd., Series 
 
  
2020-8A, Class X, 1.053% (3 Month USD LIBOR + 
 
  
85 bps), 7/20/31 (144A) 
699,996 
3,000,000(a)  
Golub Capital Partners CLO 24M-R, Ltd., Series 
 
  
2015-24A, Class AR, 1.849% (3 Month USD LIBOR + 
 
  
160 bps), 11/5/29 (144A) 
2,922,888 
1,821,000(a)  
Golub Capital Partners CLO 25M, Ltd., Series 2015-25A, 
 
  
Class AR, 1.629% (3 Month USD LIBOR + 
 
  
138 bps), 5/5/30 (144A) 
1,759,610 
10,000,000(a)  
Golub Capital Partners CLO 34M, Ltd., Series 2017-34A, 
 
  
Class AR, 1.949% (3 Month USD LIBOR + 
 
  
170 bps), 3/14/31 (144A) 
9,806,360 
5,000,000(a)  
Golub Capital Partners CLO 46M, Ltd., Series 2019-46A, 
 
  
Class A1A, 2.935% (3 Month USD LIBOR + 
 
  
180 bps), 4/20/32 (144A) 
4,886,215 
1,512,751  
GreatAmerica Leasing Receivables Funding LLC, Series 
 
  
2019-1, Class A2, 2.97%, 6/15/21 (144A) 
1,516,694 
1,827,778(a)  
Greywolf CLO III, Ltd., Series 2020-3RA, Class XR, 
 
  
0.758% (3 Month USD LIBOR + 50 bps), 4/15/33 (144A) 
1,812,183 
24,313(a)  
GSRPM Mortgage Loan Trust, Series 2006-1, Class A1, 
 
  
0.448% (1 Month USD LIBOR + 30 bps), 3/25/35 (144A) 
24,268 
4,133,716(a)  
HANA SBA LOAN TRUST, Series 2019-1, Class A, 
 
  
2.185% (1 Month USD LIBOR + 200 bps), 
 
  
8/25/45 (144A) 
3,976,947 
833,333(a)  
Harbor Park CLO, Ltd., Series 2018-1A, Class X, 1.172% 
 
  
(3 Month USD LIBOR + 90 bps), 1/20/31 (144A) 
833,332 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 29
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
30,819  
Hero Residual Funding, Series 2016-1R, Class A1, 
 
  
4.5%, 9/21/42 (144A) 
$ 30,938 
587,853(a)  
Hertz Fleet Lease Funding LP, Series 2017-1, Class A1, 
 
  
0.806% (1 Month USD LIBOR + 65 bps), 4/10/31 (144A) 
587,674 
3,310,031(a)  
Hertz Fleet Lease Funding LP, Series 2018-1, Class A1, 
 
  
0.656% (1 Month USD LIBOR + 50 bps), 5/10/32 (144A) 
3,298,739 
275,598(a)  
Hertz Fleet Lease Funding LP, Series 2019-1, Class A1, 
 
  
0.626% (1 Month USD LIBOR + 47 bps), 1/10/33 (144A) 
276,229 
4,000,000  
HOA Funding LLC, Series 2015-1A, Class B, 9.0%, 
 
  
8/20/44 (144A) 
3,705,786 
86,511(a)  
Home Equity Asset Trust, Series 2004-8, Class M1, 
 
  
1.018% (1 Month USD LIBOR + 87 bps), 3/25/35 
86,460 
1,903,461(a)  
Home Equity Asset Trust, Series 2005-3, Class M4, 
 
  
0.788% (1 Month USD LIBOR + 64 bps), 8/25/35 
1,903,093 
78,600(a)  
Home Equity Asset Trust, Series 2005-7, Class M1, 
 
  
0.598% (1 Month USD LIBOR + 45 bps), 1/25/36 
78,312 
2,239,760(a)  
Home Equity Asset Trust, Series 2006-3, Class 2A4, 
 
  
0.458% (1 Month USD LIBOR + 31 bps), 7/25/36 
2,237,803 
3,000,000(a)  
Home Partners of America Trust, Series 2017-1, 
 
  
Class C, 1.701% (1 Month USD LIBOR + 155 bps), 
 
  
7/17/34 (144A) 
2,997,514 
2,500,000(a)  
Home Partners of America Trust, Series 2017-1, Class D, 
 
  
2.051% (1 Month USD LIBOR + 190 bps), 
 
  
7/17/34 (144A) 
2,498,625 
2,000,000(a)  
Home Partners of America Trust, Series 2018-1, Class C, 
 
  
1.401% (1 Month USD LIBOR + 125 bps), 
 
  
7/17/37 (144A) 
1,998,749 
6,848,604  
HPEFS Equipment Trust, Series 2019-1A, Class A2, 
 
  
2.19%, 9/20/29 (144A) 
6,888,268 
528,427(a)  
HSI Asset Securitization Corp. Trust, Series 2006-OPT1, 
 
  
Class 2A4, 0.448% (1 Month USD LIBOR + 
 
  
30 bps), 12/25/35 
527,867 
156,988(a)  
HSI Asset Securitization Corp. Trust, Series 2006-OPT2, 
 
  
Class M1, 0.518% (1 Month USD LIBOR + 
 
  
37 bps), 1/25/36 
157,269 
2,067,000(a)  
Invitation Homes Trust, Series 2017-SFR2, Class C, 
 
  
1.601% (1 Month USD LIBOR + 145 bps), 
 
  
12/17/36 (144A) 
2,072,142 
10,981,389(a)  
Invitation Homes Trust, Series 2018-SFR1, Class A, 
 
  
0.851% (1 Month USD LIBOR + 70 bps), 
 
  
3/17/37 (144A) 
10,865,342 
4,000,000(a)  
Invitation Homes Trust, Series 2018-SFR1, Class B, 
 
  
1.101% (1 Month USD LIBOR + 95 bps), 
 
  
3/17/37 (144A) 
3,961,454 
7,165,000(a)  
Invitation Homes Trust, Series 2018-SFR1, Class D, 
 
  
1.601% (1 Month USD LIBOR + 145 bps), 
 
  
3/17/37 (144A) 
7,156,115 
 
The accompanying notes are an integral part of these financial statements.
30 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
5,479,251(a)  
Invitation Homes Trust, Series 2018-SFR1, Class E, 
 
 
 
2.151% (1 Month USD LIBOR + 200 bps), 
 
 
 
3/17/37 (144A) 
$ 5,485,232 
1,750,000(a)  
Invitation Homes Trust, Series 2018-SFR2, Class C, 
 
 
 
1.432% (1 Month USD LIBOR + 128 bps), 
 
 
 
6/17/37 (144A) 
1,748,063 
10,000,000(a)  
Invitation Homes Trust, Series 2018-SFR2, Class D, 
 
 
 
1.602% (1 Month USD LIBOR + 145 bps), 
 
 
 
6/17/37 (144A) 
9,981,284 
6,856,743(a)  
Invitation Homes Trust, Series 2018-SFR3, Class E, 
 
 
 
2.151% (1 Month USD LIBOR + 200 bps), 
 
 
 
7/17/37 (144A) 
6,861,298 
13,821,000(a)  
Invitation Homes Trust, Series 2018-SFR4, Class E, 
 
 
 
2.101% (1 Month USD LIBOR + 195 bps), 
 
 
 
1/17/38 (144A) 
13,790,663 
5,900,000(a)  
Ivy Hill Middle Market Credit Fund X, Ltd., Series 10A, 
 

 
Class A1AR, 1.522% (3 Month USD LIBOR +
 
 
 
125 bps), 7/18/30 (144A) 
5,691,046 
71,205(a)  
Jefferson Mill CLO, Ltd., Series 2015-1I, Class XR, 
 
 
 
0.872% (3 Month USD LIBOR + 60 bps), 10/20/31 
71,204 
1,400,000  
Kabbage Funding LLC, Series 2019-1, Class C, 4.611%, 
 
 
 
3/15/24 (144A) 
1,323,280 
478,567(a)  
KVK CLO, Ltd., Series 2018-1A, Class A, 1.183% 
 
 
 
(3 Month USD LIBOR + 93 bps), 5/20/29 (144A) 
473,727 
15,000,000(a)  
KVK CLO, Ltd., Series 2018-1A, Class B, 1.903% 
 
 
 
(3 Month USD LIBOR + 165 bps), 5/20/29 (144A) 
14,846,340 
5,500,000(a)  
Lake Shore MM CLO III LLC, Series 2020-1A, Class A, 
 
 
 
0.0% (3 Month USD LIBOR + 230 bps), 10/15/29 (144A) 
5,500,000 
3,777,028(a)  
Laurel Road Prime Student Loan Trust, Series 2017-C, 
 
 
 
Class A1, 0.698% (1 Month USD LIBOR + 
 
 
 
55 bps), 11/25/42 (144A) 
3,752,703 
2,100,000  
Laurel Road Prime Student Loan Trust, Series 2020-A, 
 
 
 
Class A1FX, 0.72%, 11/25/50 (144A) 
2,100,209 
350,000(a)  
LCM 28, Ltd., Series 28A, Class X, 1.172% (3 Month USD 
 
 
 
LIBOR + 90 bps), 10/20/30 (144A) 
349,994 
8,000,000(a)  
LCM XVIII LP, Series 18A, Class A1R, 1.292% (3 Month 
 
 
 
USD LIBOR + 102 bps), 4/20/31 (144A) 
7,872,504 
612,763(a)  
Lehman XS Trust, Series 2005-4, Class 1A3, 0.948% (1 
 
 
 
Month USD LIBOR + 80 bps), 10/25/35 
610,829 
1,230,407  
Lendingpoint Asset Securitization Trust, Series 2019-1, 
 
 
 
Class A, 3.154%, 8/15/25 (144A) 
1,231,196 
2,500,000  
Lendingpoint Asset Securitization Trust, Series 2019-1, 
 
 
 
Class B, 3.613%, 8/15/25 (144A) 
2,503,921 
6,407,964  
Lendingpoint Asset Securitization Trust, Series 2020-1, 
 
 
 
Class A, 2.512%, 2/10/26 (144A) 
6,411,764 
5,912,753  
LL ABS Trust, Series 2019-1A, Class A, 2.87%, 
 
 
 
3/15/27 (144A) 
5,938,041 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 31
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
5,000,000  
LL ABS Trust, Series 2020-1A, Class A, 2.33%, 
 
  
1/17/28 (144A) 
$ 5,000,676 
7,500,000(a)  
LoanCore Issuer, Ltd., Series 2019-CRE2, Class A, 
 
  
1.282% (1 Month USD LIBOR + 113 bps), 
 
  
5/15/36 (144A) 
7,367,015 
8,300,000(a)  
M360 LLC, Series 2019-CRE2, Class A, 1.552% 
 
  
(1 Month USD LIBOR + 140 bps), 9/15/34 (144A) 
8,082,784 
1,000,000(a)  
Madison Park Funding XII, Ltd., Series 2014-12A, 
 
  
Class CR, 2.622% (3 Month USD LIBOR + 
 
  
235 bps), 7/20/26 (144A) 
1,000,014 
250,000(a)  
Magnetite VII Ltd., Series 2012-7A, Class A1R2, 1.075% 
 
  
(3 Month USD LIBOR + 80 bps), 1/15/28 (144A) 
247,880 
8,629,000(a)  
Magnetite XVIII Ltd., Series 2016-18A, Class AR, 1.36% 
 
  
(3 Month USD LIBOR + 108 bps), 11/15/28 (144A) 
8,580,669 
1,662,969  
Marlette Funding Trust, Series 2017-1A, Class C, 6.658%, 
 
  
3/15/24 (144A) 
1,664,237 
5,745,514  
Marlette Funding Trust, Series 2020-1A, Class A, 2.24%, 
 
  
3/15/30 (144A) 
5,789,089 
6,138,049  
Marlin Receivables LLC, Series 2018-1A, Class A3, 3.36%, 
 
  
4/20/23 (144A) 
6,157,184 
15,500,000(a)  
Master Credit Card Trust, Series 2019-1A, Class A, 
 
  
0.636% (1 Month USD LIBOR + 48 bps), 7/21/22 
 
  
(144A) 
15,513,871 
12,000,000(a)  
Master Credit Card Trust II, Series 2019-2A, Class A, 
 
  
0.546% (1 Month USD LIBOR + 39 bps), 1/21/23 
 
  
(144A) 
12,015,359 
242,204(a)  
Merrill Lynch Mortgage Investors Trust, Series 
 
  
2004-OPT1, Class A1B, 1.008% (1 Month USD LIBOR + 
 
  
86 bps), 6/25/35 
239,926 
1,764,106(a)  
Merrill Lynch Mortgage Investors Trust, Series 
 
  
2005-AR1, Class M1, 0.898% (1 Month USD LIBOR + 
 
  
75 bps), 6/25/36 
1,759,196 
4,701,420(c)  
MFA LLC, Series 2017-NPL1, Class A1, 3.352%, 
 
  
11/25/47 (144A) 
4,714,492 
4,884,540  
MMAF Equipment Finance LLC, Series 2019-B, 
 
  
Class A2, 2.07%, 10/12/22 (144A) 
4,929,499 
4,500,000(a)  
Monroe Capital Mml CLO, Ltd., Series 2017-1A, 
 
  
Class A, 1.858% (3 Month USD LIBOR + 160 bps), 
 
  
4/22/29 (144A) 
4,381,839 
1,628,989(a)  
Morgan Stanley Capital I, Inc. Trust, Series 2006-NC2, 
 
  
Class A2D, 0.438% (1 Month USD LIBOR + 
 
  
29 bps), 2/25/36 
1,598,811 
529,261(a)  
Morgan Stanley Home Equity Loan Trust, Series 
 
  
2006-2, Class A4, 0.428% (1 Month USD LIBOR + 
 
  
28 bps), 2/25/36 
522,104 
2,484,434(a)  
National Collegiate Trust, Series 2007-A, Class A, 
 
  
0.443% (1 Month USD LIBOR + 30 bps), 
 
  
5/25/31 (144A) 
2,410,817 
 
The accompanying notes are an integral part of these financial statements.
32 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
4,823,575(b)  
Nationstar HECM Loan Trust, Series 2019-1A, Class A, 
 
  
2.651%, 6/25/29 (144A) 
$ 4,839,833 
4,000,000(b)  
Nationstar HECM Loan Trust, Series 2020-1A, Class A1, 
 
  
1.269%, 9/25/30 (144A) 
3,999,998 
5,633,287(a)  
Nationstar Home Equity Loan Trust, Series 2006-B, 
 
  
Class AV4, 0.428% (1 Month USD LIBOR + 
 
  
28 bps), 9/25/36 
5,605,931 
4,000,000(a)  
Navistar Financial Dealer Note Master Trust, Series 
 

 
2020-1, Class A, 1.098% (1 Month USD LIBOR +
 
  
95 bps), 7/25/25 (144A) 
4,023,199 
2,041,722  
Nelnet Private Education Loan Trust, Series 2016-A, 
 
  
Class A1B, 3.6%, 12/26/40 (144A) 
2,080,798 
8,172,491(a)  
Nelnet Student Loan Trust, Series 2005-2, Class A5, 
 
  
0.325% (3 Month USD LIBOR + 10 bps), 3/23/37 
7,890,674 
6,873,304(a)  
Neuberger Berman CLO XX, Ltd., Series 2015-20A, 
 
  
Class AR, 1.075% (3 Month USD LIBOR + 
 
  
80 bps), 1/15/28 (144A) 
6,822,112 
2,750,000(a)  
Neuberger Berman CLO XXII, Ltd., Series 2016-22A, 
 
  
Class XR, 1.173% (3 Month USD LIBOR + 
 
  
90 bps), 10/17/30 (144A) 
2,749,994 
685,680(a)  
Newtek Small Business Loan Trust, Series 2016-1A, 
 
  
Class A, 3.148% (1 Month USD LIBOR + 
 
  
300 bps), 2/25/42 (144A) 
684,535 
3,730,378(a)  
Newtek Small Business Loan Trust, Series 2017-1, 
 
  
Class A, 2.148% (1 Month USD LIBOR + 
 
  
200 bps), 2/25/43 (144A) 
3,647,701 
4,577,601(a)  
Newtek Small Business Loan Trust, Series 2018-1, 
 
  
Class A, 1.848% (1 Month USD LIBOR + 
 
  
170 bps), 2/25/44 (144A) 
4,463,282 
3,521,232(a)  
Newtek Small Business Loan Trust, Series 2018-1, 
 
  
Class B, 3.148% (1 Month USD LIBOR + 
 
  
300 bps), 2/25/44 (144A) 
3,200,332 
11,215,109(a)  
Newtek Small Business Loan Trust, Series 2019-1, 
 
  
Class A, 2.35% (PRIME + -90 bps), 12/25/44 (144A) 
11,088,345 
2,392,557(a)  
Newtek Small Business Loan Trust, Series 2019-1, 
 
  
Class B, 2.648% (1 Month USD LIBOR + 
 
  
250 bps), 12/25/44 (144A) 
2,219,335 
18,300,000(a)  
NextGear Floorplan Master Owner Trust, Series 
 
  
2019-2A, Class A1, 0.852% (1 Month USD LIBOR + 
 
  
70 bps), 10/15/24 (144A) 
17,910,995 
19,500,000(a)  
NextGear Floorplan Master Owner Trust, Series 
 
  
2020-1A, Class A1, 0.952% (1 Month USD LIBOR + 
 
  
80 bps), 2/15/25 (144A) 
19,292,298 
8,767,839  
NMEF Funding LLC, Series 2019-A, Class A, 2.73%, 
 
  
8/17/26 (144A) 
8,811,225 
154,238(a)  
NovaStar Mortgage Funding Trust, Series 2003-1, 
 
  
Class A2, 0.928% (1 Month USD LIBOR + 
 
  
78 bps), 5/25/33 
152,067 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 33
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
12,498,516  
Oasis LLC, Series 2020-1A, Class A, 3.82%, 
 
 
 
1/15/32 (144A) 
$ 12,541,733 
7,692,541  
Oasis LLC, Series 2020-2A, Class A, 4.262%, 
 
 
 
5/15/32 (144A) 
7,706,519 
500,000(a)  
Octagon Investment Partners XVI, Ltd., Series 
 
 
 
2013-1A, Class XR, 0.823% (3 Month USD LIBOR + 
 
 
 
55 bps), 7/17/30 (144A) 
499,996 
2,625,000(a)  
Octagon Investment Partners XXI, Ltd., Series 
 
 
 
2014-1A, Class XRR, 1.015% (3 Month USD LIBOR + 
 
 
 
75 bps), 2/14/31 (144A) 
2,624,858 
2,843,750(a)  
Octagon Investment Partners XXII, Ltd., Series 
 
 
 
2014-1A, Class XRR, 0.908% (3 Month USD LIBOR + 
 
 
 
65 bps), 1/22/30 (144A) 
2,843,687 
9,250,000  
Octane Receivables Trust, Series 2020-1A, Class A, 
 
 
 
1.71%, 2/20/25 (144A) 
9,250,361 
1,607,143(a)  
OHA Credit Funding 3, Ltd., Series 2019-3A, Class X, 
 
 
 
0.922% (3 Month USD LIBOR + 65 bps), 
 
 
 
7/20/32 (144A) 
1,607,141 
2,750,000(a)  
OHA Credit Funding 5, Ltd., Series 2020-5A, Class X, 
 
 
 
1.856% (3 Month USD LIBOR + 55 bps), 
 
 
 
4/18/33 (144A) 
2,707,614 
2,098,767(a)  
OneMain Financial Issuance Trust, Series 2017-1A, 
 
 
 
Class A2, 0.951% (1 Month USD LIBOR + 
 
 
 
80 bps), 9/14/32 (144A) 
2,100,439 
1,475,000  
OneMain Financial Issuance Trust, Series 2019-1A, 
 
 
 
Class A, 3.48%, 2/14/31 (144A) 
1,512,170 
170,000  
OneMain Financial Issuance Trust, Series 2019-1A, 
 
 
 
Class B, 3.79%, 2/14/31 (144A) 
176,568 
5,126,356(a)  
Option One Mortgage Loan Trust, Series 2005-3, 
 
 
 
Class M2, 0.883% (1 Month USD LIBOR + 
 
 
 
74 bps), 8/25/35 
5,074,556 
1,209,852(a)  
Option One Mortgage Loan Trust, Series 2005-4, 
 
 
 
Class M1, 0.808% (1 Month USD LIBOR + 
 
 
 
66 bps), 11/25/35 
1,207,707 
12,950,000(a)  
Orec, Ltd., Series 2018-CRE1, Class A, 1.332% 
 
 
 
(1 Month USD LIBOR + 118 bps), 6/15/36 (144A) 
12,760,242 
13,500,000(a)  
Owl Rock CLO II, Ltd., Series 2019-2A, Class A1L, 
 
 
 
2.022% (3 Month USD LIBOR + 175 bps), 
 
 
 
1/20/31 (144A) 
13,346,060 
2,000,000(a)  
Owl Rock CLO IV, Ltd., Series 2020-4A, Class A1, 3.17% 
 
 
 
(3 Month USD LIBOR + 262 bps), 5/20/29 (144A) 
2,002,326 
18,327  
Oxford Finance Funding LLC, Series 2016-1A, Class A, 
 
 
 
3.968%, 6/17/24 (144A) 
18,334 
875,000(a)  
OZLM VIII, Ltd., Series 2014-8A, Class XRR, 0.973% 
 
 
 
(3 Month USD LIBOR + 70 bps), 10/17/29 (144A) 
874,998 
4,250,000(a)  
Palmer Square Loan Funding, Ltd., Series 2018-1A, 
 
 
 
Class A2, 1.325% (3 Month USD LIBOR + 
 
 
 
105 bps), 4/15/26 (144A) 
4,162,327 
 
The accompanying notes are an integral part of these financial statements.
34 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,000,000(a)  
Palmer Square Loan Funding, Ltd., Series 2018-2A, 
 
 
 
Class D, 4.225% (3 Month USD LIBOR + 
 
 
 
395 bps), 7/15/26 (144A) 
$ 937,218 
4,000,000(a)  
Palmer Square Loan Funding, Ltd., Series 2020-4A, 
 
 
 
Class C, 0.0% (3 Month USD LIBOR + 
 
 
 
360 bps), 11/25/28 (144A) 
4,000,000 
700,504(a)  
PARTS Student Loan Trust, Series 2007-CT1, Class A, 
 
 
 
0.44% (3 Month USD LIBOR + 19 bps), 2/25/33 (144A) 
684,283 
8,889,584  
Pawnee Equipment Receivables LLC, Series 2019-1, 
 
 
 
Class A2, 2.29%, 10/15/24 (144A) 
8,973,255 
4,250,000  
Pawnee Equipment Receivables LLC, Series 2020-1, 
 
 
 
Class A, 1.37%, 11/17/25 (144A) 
4,242,988 
30,000,000(a)  
PFS Financing Corp., Series 2019-B, Class A, 0.702% 
 
 
 
(1 Month USD LIBOR + 55 bps), 9/15/23 (144A) 
30,046,947 
33,154(a)  
Popular ABS Mortgage Pass-Through Trust, Series 
 
 
 
2005-A, Class M1, 0.578% (1 Month USD LIBOR + 
 
 
 
43 bps), 6/25/35 
33,134 
50,047  
Prosper Marketplace Issuance Trust, Series 2019-1A, 
 
 
 
Class A, 3.54%, 4/15/25 (144A) 
50,074 
2,852,315  
Prosper Marketplace Issuance Trust, Series 2019-4A, 
 
 
 
Class A, 2.48%, 2/17/26 (144A) 
2,864,755 
482,901  
Purchasing Power Funding LLC, Series 2018-A, 
 
 
 
Class A, 3.34%, 8/15/22 (144A) 
483,088 
2,600,000  
Purchasing Power Funding LLC, Series 2018-A, 
 
 
 
Class B, 3.58%, 8/15/22 (144A) 
2,598,217 
6,333,904(a)  
RAAC Trust, Series 2006-RP1, Class M2, 1.348% 
 
 
 
(1 Month USD LIBOR + 120 bps), 10/25/45 (144A) 
6,363,221 
551,394(a)  
RAMP Trust, Series 2005-EFC6, Class M2, 0.793% 
 
 
 
(1 Month USD LIBOR + 65 bps), 11/25/35 
549,496 
4,615(a)  
RAMP Trust, Series 2006-EFC2, Class A3, 0.308% 
 
 
 
(1 Month USD LIBOR + 16 bps), 12/25/36 
4,613 
1,743(a)  
RAMP Trust, Series 2006-RZ3, Class A3, 0.438% 
 
 
 
(1 Month USD LIBOR + 29 bps), 8/25/36 
1,742 
2,779,300(a)  
RAMP Trust, Series 2006-RZ4, Class A3, 0.418% 
 
 
 
(1 Month USD LIBOR + 27 bps), 10/25/36 
2,749,396 
402,619(a)  
RASC Trust, Series 2005-EMX4, Class M2, 0.808% 
 
 
 
(1 Month USD LIBOR + 66 bps), 11/25/35 
402,380 
921,797(a)  
RASC Trust, Series 2005-KS1, Class M1, 0.823% 
 
 
 
(1 Month USD LIBOR + 68 bps), 2/25/35 
918,889 
202,547(a)  
RASC Trust, Series 2005-KS7, Class M4, 1.018% 
 
 
 
(1 Month USD LIBOR + 87 bps), 8/25/35 
202,508 
4,000,000(a)  
RASC Trust, Series 2005-KS7, Class M5, 1.063% 
 
 
 
(1 Month USD LIBOR + 92 bps), 8/25/35 
3,970,434 
254,989(a)  
RASC Trust, Series 2005-KS8, Class M3, 0.628% 
 
 
 
(1 Month USD LIBOR + 48 bps), 8/25/35 
254,845 
1,802(a)  
RASC Trust, Series 2005-KS11, Class M1, 0.548% 
 
 
 
(1 Month USD LIBOR + 40 bps), 12/25/35 
1,802 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 35
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
9,941,784(a)  
ReadyCap Lending Small Business Loan Trust, Series 
 

 
2019-2, Class A, 2.75% (PRIME + -50 bps),
 
  
12/27/44 (144A) 
$ 9,264,251 
250,000(a)  
Regatta VI Funding Ltd., Series 2016-1A, Class AR, 
 
  
1.352% (3 Month USD LIBOR + 108 bps), 
 
  
7/20/28 (144A) 
248,720 
6,400,000  
Republic FInance Issuance Trust, Series 2019-A, 
 
  
Class A, 3.43%, 11/22/27 (144A) 
6,506,394 
7,500,000(a)  
Rosy, Series 2018-1, Class A2, 3.402% (1 Month USD 
 
  
LIBOR + 325 bps), 12/15/25 (144A) 
7,200,000 
30,290(a)  
Salomon Mortgage Loan Trust, Series 2001-CB4, 
 
  
Class 1A1, 1.048% (1 Month USD LIBOR + 
 
  
90 bps), 11/25/33 
30,014 
9,292,957(a)  
Santander Drive Auto Receivables Trust, Series 2020-1, 
 
  
Class A2B, 1.702% (1 Month USD LIBOR + 
 
  
155 bps), 1/17/23 
9,340,171 
2,111,603(a)  
Saxon Asset Securities Trust, Series 2006-2, Class A3C, 
 
  
0.298% (1 Month USD LIBOR + 15 bps), 9/25/36 
2,103,079 
255,468  
SCF Equipment Leasing LLC, Series 2017-1A, Class A, 
 
  
3.77%, 1/20/23 (144A) 
256,114 
1,263,626  
SCF Equipment Leasing LLC, Series 2017-2A, Class A, 
 
  
3.41%, 12/20/23 (144A) 
1,267,165 
255,443  
SCF Equipment Leasing LLC, Series 2018-1A, Class A2, 
 
  
3.63%, 10/20/24 (144A) 
257,350 
2,943,352  
SCF Equipment Leasing LLC, Series 2019-1A, Class A1, 
 
  
3.04%, 3/20/23 (144A) 
2,947,535 
11,069,185  
SCF Equipment Leasing LLC, Series 2019-2A, Class A1, 
 
  
2.22%, 6/20/24 (144A) 
11,124,293 
17,629(a)  
Securitized Asset Backed Receivables LLC Trust, Series 
 
  
2005-OP2, Class M1, 0.578% (1 Month USD LIBOR + 
 
  
43 bps), 10/25/35 
17,567 
492,637(a)  
Security National Mortgage Loan Trust, Series 2007-1A, 
 
  
Class 2A, 0.498% (1 Month USD LIBOR + 
 
  
35 bps), 4/25/37 (144A) 
491,162 
2,022,999(a)  
SG Mortgage Securities Trust, Series 2005-OPT1, 
 
  
Class M1, 0.578% (1 Month USD LIBOR + 
 
  
43 bps), 10/25/35 
2,018,596 
7,537,558(a)  
SLM Private Credit Student Loan Trust, Series 2007-A, 
 
  
Class A4A, 0.553% (3 Month USD LIBOR + 
 
  
24 bps), 12/16/41 
7,245,941 
13,964,140(a)  
SLM Student Loan Trust, Series 2006-10, Class A6, 
 
  
0.395% (3 Month USD LIBOR + 15 bps), 3/25/44 
13,222,119 
4,336,669  
Small Business Lending Trust, Series 2019-A, Class A, 
 
  
2.85%, 7/15/26 (144A) 
4,266,458 
6,897,191  
Small Business Lending Trust, Series 2020-A, Class A, 
 
  
2.62%, 12/15/26 (144A) 
6,847,658 
1,000,000  
Small Business Lending Trust, Series 2020-A, Class C, 
 
  
5.01%, 12/15/26 (144A) 
701,920 
 
The accompanying notes are an integral part of these financial statements.
36 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
6,289,464  
Sofi Consumer Loan Program LLC, Series 2016-1, 
 
 
 
Class A, 3.26%, 8/25/25 (144A) 
$ 6,330,720 
91,815  
Sofi Consumer Loan Program LLC, Series 2016-4, 
 
 
 
Class A, 3.18%, 11/25/25 (144A) 
91,963 
382,618  
Sofi Consumer Loan Program LLC, Series 2017-1, 
 
 
 
Class A, 3.28%, 1/26/26 (144A) 
383,287 
309,043  
Sofi Consumer Loan Program LLC, Series 2017-3, 
 
 
 
Class A, 2.77%, 5/25/26 (144A) 
310,752 
4,300,000  
Sofi Consumer Loan Program Trust, Series 2018-1, 
 
 
 
Class B, 3.65%, 2/25/27 (144A) 
4,420,079 
2,415,058  
Sofi Consumer Loan Program Trust, Series 2019-1, 
 
 
 
Class A, 3.24%, 2/25/28 (144A) 
2,439,274 
1,315,641  
Sofi Consumer Loan Program Trust, Series 2019-2, 
 
 
 
Class A, 3.01%, 4/25/28 (144A) 
1,330,631 
540,701(a)  
Sofi Professional Loan Program LLC, Series 2015-B, 
 
 
 
Class A1, 1.198% (1 Month USD LIBOR + 
 
 
 
105 bps), 4/25/35 (144A) 
540,827 
671,702(a)  
Sofi Professional Loan Program LLC, Series 2015-C, 
 
 
 
Class A1, 1.198% (1 Month USD LIBOR + 
 
 
 
105 bps), 8/27/35 (144A) 
672,007 
1,128,956(a)  
Sofi Professional Loan Program LLC, Series 2015-D, 
 
 
 
Class A1, 1.648% (1 Month USD LIBOR + 
 
 
 
150 bps), 10/27/36 (144A) 
1,135,654 
1,158,734(a)  
Sofi Professional Loan Program LLC, Series 2016-A, 
 
 
 
Class A1, 1.898% (1 Month USD LIBOR + 
 
 
 
175 bps), 8/25/36 (144A) 
1,167,199 
797,101(a)  
Sofi Professional Loan Program LLC, Series 2016-B, 
 
 
 
Class A1, 1.348% (1 Month USD LIBOR + 
 
 
 
120 bps), 6/25/33 (144A) 
798,833 
2,126,021(a)  
Sofi Professional Loan Program LLC, Series 2016-C, 
 
 
 
Class A1, 1.248% (1 Month USD LIBOR + 
 
 
 
110 bps), 10/27/36 (144A) 
2,125,591 
519,890(a)  
Sofi Professional Loan Program LLC, Series 2016-D, 
 
 
 
Class A1, 1.098% (1 Month USD LIBOR + 
 
 
 
95 bps), 1/25/39 (144A) 
520,089 
1,259,711(a)  
Sofi Professional Loan Program LLC, Series 2016-E, 
 
 
 
Class A1, 0.998% (1 Month USD LIBOR + 
 
 
 
85 bps), 7/25/39 (144A) 
1,257,059 
360,606(a)  
Sofi Professional Loan Program LLC, Series 2017-A, 
 
 
 
Class A1, 0.848% (1 Month USD LIBOR + 
 
 
 
70 bps), 3/26/40 (144A) 
360,388 
437,904(a)  
Sofi Professional Loan Program LLC, Series 2017-C, 
 
 
 
Class A1, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/25/40 (144A) 
436,477 
724,374(a)  
Sofi Professional Loan Program LLC, Series 2017-E, 
 
 
 
Class A1, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 11/26/40 (144A) 
723,249 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 37
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
1,124,409(a)  
Sofi Professional Loan Program LLC, Series 2018-A, 
 
  
Class A1, 0.498% (1 Month USD LIBOR + 
 
  
35 bps), 2/25/42 (144A) 
$ 1,114,408 
11,363  
Sofi Professional Loan Program LLC, Series 2018-A, 
 
  
Class A2A, 2.39%, 2/25/42 (144A) 
11,370 
4,695,146  
Sofi Professional Loan Program LLC, Series 2019-C, 
 
  
Class A1FX, 2.13%, 11/16/48 (144A) 
4,729,629 
2,000,000(a)  
Sound Point Clo XIV Ltd., Series 2016-3A, Class AR, 
 
  
1.406% (3 Month USD LIBOR + 115 bps), 
 
  
1/23/29 (144A) 
1,980,944 
2,000,000(a)  
Sound Point CLO XXV, Ltd., Series 2019-4A, Class X, 
 
  
0.925% (3 Month USD LIBOR + 65 bps), 
 
  
1/15/33 (144A) 
1,999,998 
4,650,000  
SpringCastle America Funding LLC, Series 2020-AA, 
 
  
Class A, 1.97%, 9/25/37 (144A) 
4,666,688 
10,986,802  
Springleaf Funding Trust, Series 2015-BA, Class A, 
 
  
3.48%, 5/15/28 (144A) 
11,033,608 
6,000,000(a)  
Starwood Waypoint Homes Trust, Series 2017-1, 
 
  
Class E, 2.752% (1 Month USD LIBOR + 260 bps), 
 
  
1/17/35 (144A) 
6,006,758 
77,031(a)  
Structured Asset Investment Loan Trust, Series 
 
  
2005-HE1, Class M1, 0.618% (1 Month USD LIBOR + 
 
  
47 bps), 7/25/35 
77,763 
2,775,856(a)  
Structured Asset Investment Loan Trust, Series 
 
  
2005-HE3, Class M1, 0.868% (1 Month USD LIBOR + 
 
  
72 bps), 9/25/35 
2,757,389 
73,834(a)  
Structured Asset Securities Corp. Mortgage Loan Trust,
 

 
Series 2005-NC2, Class M4, 0.853% (1 Month
 
  
USD LIBOR + 71 bps), 5/25/35 
73,337 
3,767,642(a)  
Structured Asset Securities Corp. Mortgage Loan Trust, 
 

 
Series 2006-OPT1, Class A1, 0.328% (1 Month
 
  
USD LIBOR + 18 bps), 4/25/36 
3,578,541 
1,361,170(a)  
Structured Asset Securities Corp. Mortgage Loan Trust, 
 

 
Series 2007-TC1, Class A, 0.448% (1 Month USD
 
  
LIBOR + 30 bps), 4/25/31 (144A) 
1,352,075 
1,151,202  
Tax Ease Funding LLC, Series 2016-1A, Class A, 3.131%, 
 
  
6/15/28 (144A) 
1,153,650 
139,642  
TCF Auto Receivables Owner Trust, Series 2016-PT1A, 
 
  
Class A, 1.93%, 6/15/22 (144A) 
139,793 
3,954,123(a)  
Terwin Mortgage Trust, Series 2006-3, Class 1A2, 0.378% 
 
  
(1 Month USD LIBOR + 23 bps), 4/25/37 (144A) 
3,924,530 
5,500,000  
Tesla Auto Lease Trust, Series 2020-A, Class A2, 0.55%, 
 
  
5/22/23 (144A) 
5,508,466 
2,000,000(a)  
THL Credit Wind River CLO, Ltd., Series 2012-1A, 
 
  
Class BR2, 1.725% (3 Month USD LIBOR + 
 
  
145 bps), 1/15/26 (144A) 
1,998,488 
375,000(a)  
THL Credit Wind River CLO, Ltd., Series 2015-1A,
 
  
Class X, 0.922% (3 Month USD LIBOR + 
 
  
65 bps), 10/20/30 (144A) 
373,973 
 
The accompanying notes are an integral part of these financial statements.
38 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,000,000(a)  
THL Credit Wind River CLO, Ltd., Series 2016-1A, 
 
 
 
Class AR, 1.325% (3 Month USD LIBOR + 
 
 
 
105 bps), 7/15/28 (144A) 
$ 1,987,968 
31,182,000  
Tidewater Auto Receivables Trust, Series 2020-AA, 
 
 
 
Class A2, 1.39%, 8/15/24 (144A) 
31,386,769 
2,750,000  
Tidewater Auto Receivables Trust, Series 2020-AA, 
 
 
 
Class E, 3.35%, 7/17/28 (144A) 
2,707,846 
2,221,427  
TLF National Tax Lien Trust, Series 2017-1A, Class A, 
 
 
 
3.09%, 12/15/29 (144A) 
2,236,076 
11,368,397(a)  
Towd Point Asset Trust, Series 2018-SL1, Class A, 
 
 
 
0.775% (1 Month USD LIBOR + 60 bps), 1/25/46 (144A) 
11,191,119 
11,000,000(a)  
Towd Point Asset Trust, Series 2018-SL1, Class B, 
 
 
 
1.225% (1 Month USD LIBOR + 105 bps), 
 
 
 
1/25/46 (144A) 
10,189,374 
307,957(b)  
Towd Point Mortgage Trust, Series 2015-4, Class A1, 
 
 
 
3.5%, 4/25/55 (144A) 
311,059 
1,587,045(b)  
Towd Point Mortgage Trust, Series 2015-5, Class A1B, 
 
 
 
2.75%, 5/25/55 (144A) 
1,600,951 
5,666,686(a)  
Towd Point Mortgage Trust, Series 2017-5, Class A1, 
 
 
 
0.748% (1 Month USD LIBOR + 60 bps), 2/25/57 (144A) 
5,656,198 
218,703(b)  
Towd Point Mortgage Trust, Series 2017-5, Class XA, 
 
 
 
3.5%, 2/25/57 (144A) 
218,458 
5,897,887(b)  
Towd Point Mortgage Trust, Series 2018-SJ1, Class XA, 
 
 
 
5.0%, 10/25/58 (144A) 
6,032,749 
1,072,308(b)  
Towd Point Mortgage Trust, Series 2019-HY1, Class XA, 
 
 
 
5.0%, 10/25/48 (144A) 
1,069,638 
5,040,386(a)  
Towd Point Mortgage Trust, Series 2019-HY2, 
 
 
 
Class A1, 1.148% (1 Month USD LIBOR + 100 bps), 
 
 
 
5/25/58 (144A) 
5,040,386 
2,539,129(b)  
Towd Point Mortgage Trust, Series 2019-HY2, 
 
 
 
Class XA, 5.0%, 5/25/58 (144A) 
2,539,857 
866,268(a)  
Towd Point Mortgage Trust, Series 2019-HY3, 
 
 
 
Class A1A, 1.148% (1 Month USD LIBOR + 100 bps), 
 
 
 
10/25/59 (144A) 
866,268 
7,549,166  
Towd Point Mortgage Trust, Series 2019-HY3, Class XA, 
 
 
 
4.5%, 10/25/59 (144A) 
7,481,586 
2,401,184(b)  
Towd Point Mortgage Trust, Series 2019-SJ1, Class XA, 
 
 
 
5.0%, 11/25/58 (144A) 
2,377,403 
2,197,576(b)  
Towd Point Mortgage Trust, Series 2019-SJ2, Class XA, 
 
 
 
5.0%, 11/25/58 (144A) 
2,292,570 
12,709,615(b)  
Towd Point Mortgage Trust, Series 2019-SJ3, Class A1, 
 
 
 
3.0%, 11/25/59 (144A) 
12,926,244 
11,376,710(b)  
Towd Point Mortgage Trust, Series 2019-SJ3, Class XA, 
 
 
 
4.5%, 11/25/59 (144A) 
11,376,710 
13,750,000(a)  
Trafigura Securitisation Finance Plc, Series 2018-1A, 
 
 
 
Class A1, 0.882% (1 Month USD LIBOR + 73 bps), 
 
 
 
3/15/22 (144A) 
13,517,969 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 39
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,500,000  
Trafigura Securitisation Finance Plc, Series 2018-1A, 
 
 
 
Class B, 4.29%, 3/15/22 (144A) 
$ 2,493,120 
1,884,615(a)  
Tralee CLO V, Ltd., Series 2018-5A, Class AX, 0.972% 
 
 
 
(3 Month USD LIBOR + 70 bps), 10/20/28 (144A) 
1,884,612 
16,400,000(a)  
TRTX Issuer, Ltd., Series 2019-FL3, Class C, 2.251% 
 
 
 
(1 Month USD LIBOR + 210 bps), 10/15/34 (144A) 
15,443,821 
5,602,855  
TVEST LLC, Series 2020-A, Class A, 4.5%, 
 
 
 
7/15/32 (144A) 
5,606,690 
12,000,000  
United Auto Credit Securitization Trust, Series 2018-1, 
 
 
 
Class E, 4.84%, 8/10/23 (144A) 
12,182,116 
4,877,234  
United Auto Credit Securitization Trust, Series 2019-1, 
 
 
 
Class B, 3.03%, 4/10/24 (144A) 
4,887,679 
6,301,535  
United Auto Credit Securitization Trust, Series 2020-1, 
 
 
 
Class A, 0.85%, 5/10/22 (144A) 
6,305,668 
7,452,169  
Upstart Securitization Trust, Series 2019-2, Class A, 
 
 
 
2.897%, 9/20/29 (144A) 
7,513,449 
11,861,272  
Upstart Securitization Trust, Series 2019-3, Class A, 
 
 
 
2.684%, 1/21/30 (144A) 
11,960,721 
20,114,006  
Upstart Securitization Trust, Series 2020-1, Class A, 
 
 
 
2.322%, 4/22/30 (144A) 
20,260,230 
3,521,602  
US Auto Funding LLC, Series 2019-1A, Class A, 3.61%, 
 
 
 
4/15/22 (144A) 
3,537,074 
11,633,873  
USASF Receivables LLC, Series 2020-1A, Class A, 2.47%, 
 
 
 
8/15/23 (144A) 
11,687,704 
157,895(a)  
Venture 32 CLO, Ltd., Series 2018-32RR, Class AX, 
 
 
 
1.022% (3 Month USD LIBOR + 75 bps), 7/19/31 (144A) 
157,891 
1,190,625(a)  
Venture XXI CLO, Ltd., Series 2015-21A, Class AR, 
 
 
 
1.155% (3 Month USD LIBOR + 88 bps), 7/15/27 (144A) 
1,179,049 
459,326(a)  
Verizon Owner Trust, Series 2017-3A, Class A1B, 
 
 
 
0.426% (1 Month USD LIBOR + 27 bps), 4/20/22 (144A) 
459,428 
10,010,000(a)  
Verizon Owner Trust, Series 2019-A, Class A1B, 0.486% 
 
 
 
(1 Month USD LIBOR + 33 bps), 9/20/23 
10,027,765 
23,500,000(a)  
Verizon Owner Trust, Series 2019-C, Class A1B, 0.576% 
 
 
 
(1 Month USD LIBOR + 42 bps), 4/22/24 
23,553,479 
27,000,000(a)  
Verizon Owner Trust, Series 2020-A, Class A1B, 0.426% 
 
 
 
(1 Month USD LIBOR + 27 bps), 7/22/24 
26,990,267 
15,814,788  
Veros Automobile Receivables Trust, Series 2020-1, 
 
 
 
Class A, 1.67%, 9/15/23 (144A) 
15,859,703 
2,000,000  
Veros Automobile Receivables Trust, Series 2020-1, 
 
 
 
Class B, 2.19%, 6/16/25 (144A) 
2,006,203 
5,662,615  
Volvo Financial Equipment LLC, Series 2019-2A, 
 
 
 
Class A2, 2.02%, 8/15/22 (144A) 
5,700,670 
11,250,000(a)  
Volvo Financial Equipment Master Owner Trust, 
 
 
 
Series 2018-A, Class A, 0.672% (1 Month USD LIBOR + 
 
 
 
52 bps), 7/17/23 (144A) 
11,262,303 
1,201,842  
Westgate Resorts LLC, Series 2017-1A, Class B, 4.05%, 
 
 
 
12/20/30 (144A) 
1,188,908 
 
The accompanying notes are an integral part of these financial statements.
40 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 

 ASSET BACKED SECURITIES — (continued) 
2,821,938  Westgate Resorts LLC, Series 2018-1A, Class B, 3.58%, 
 
 
 12/20/31 (144A) $ 2,796,416 
437,510  Westgate Resorts LLC, Series 2018-1A, Class C, 4.1%, 
 
 
 12/20/31 (144A) 431,189 
2,404,675  Westgate Resorts LLC, Series 2020-1A, Class A, 2.713%, 
 
 
 3/20/34 (144A) 2,445,602 
2,885,611  Westgate Resorts LLC, Series 2020-1A, Class C, 6.213%, 
 
 
 3/20/34 (144A) 3,004,969 
9,114(a)  Wilshire Mortgage Loan Trust, Series 1997-2, Class A6, 
 
 
 
0.428% (1 Month USD LIBOR + 28 bps), 5/25/28 
9,017 
 
 TOTAL ASSET BACKED SECURITIES 
 
 
 
(Cost $1,566,949,488) 
$1,562,355,864 
 
 COLLATERALIZED MORTGAGE OBLIGATIONS — 
 
 
 14.5% of Net Assets 
 
113,805(a)  Bear Stearns ALT-A Trust, Series 2004-12, Class 1A2, 
 
 
 0.988% (1 Month USD LIBOR + 84 bps), 1/25/35 $ 113,657 
345,224(a)  Bear Stearns ALT-A Trust, Series 2004-12, Class 1A3, 
 
 
 0.848% (1 Month USD LIBOR + 70 bps), 1/25/35 345,316 
170,292(a)  Bear Stearns ALT-A Trust, Series 2004-12, Class 1A4, 
 
 
 0.988% (1 Month USD LIBOR + 84 bps), 1/25/35 170,291 
90,732(b)  Bear Stearns Mortgage Securities, Inc., Series 1997-6, 
 
 
 Class 3B1, 3.219%, 6/25/30 92,066 
8,800,885(a)  Bellemeade Re, Ltd., Series 2017-1, Class M2, 3.498% 
 
 
 (1 Month USD LIBOR + 335 bps), 10/25/27 (144A) 8,598,794 
6,533,876(a)  Bellemeade Re, Ltd., Series 2018-1A, Class M1B, 1.748% 
 
 
 (1 Month USD LIBOR + 160 bps), 4/25/28 (144A) 6,469,584 
2,319,316(a)  Bellemeade Re, Ltd., Series 2018-3A, Class M1B, 1.998% 
 
 
 (1 Month USD LIBOR + 185 bps), 10/25/28 (144A) 2,302,762 
6,125,000(a)  Bellemeade Re, Ltd., Series 2018-3A, Class M2, 2.898% 
 
 
 (1 Month USD LIBOR + 275 bps), 10/25/28 (144A) 5,899,002 
8,448(a)  Bellemeade Re, Ltd., Series 2019-1A, Class M1A, 1.448% 
 
 
 (1 Month USD LIBOR + 130 bps), 3/25/29 (144A) 8,446 
5,290,000(a)  Bellemeade Re, Ltd., Series 2019-1A, Class M1B, 1.898% 
 
 
 (1 Month USD LIBOR + 175 bps), 3/25/29 (144A) 5,283,802 
2,800,000(a)  Bellemeade Re, Ltd., Series 2019-3A, Class B1, 2.648% 
 
 
 (1 Month USD LIBOR + 250 bps), 7/25/29 (144A) 2,482,943 
10,671,000(a)  Bellemeade Re, Ltd., Series 2019-3A, Class M1B, 1.748% 
 
 
 (1 Month USD LIBOR + 160 bps), 7/25/29 (144A) 10,434,725 
10,150,000(a)  Bellemeade Re, Ltd., Series 2019-4A, Class M1B, 2.175% 
 
 
 (1 Month USD LIBOR + 200 bps), 10/25/29 (144A) 9,825,114 
3,250,000(a)  Bellemeade Re, Ltd., Series 2020-2A, Class M1B, 3.348% 
 
 
 (1 Month USD LIBOR + 320 bps), 8/26/30 (144A) 3,274,050 
3,250,000(a)  Bellemeade Re, Ltd., Series 2020-2A, Class M1C, 4.148% 
 
 
 (1 Month USD LIBOR + 400 bps), 8/26/30 (144A) 3,253,872 
6,322,026(a)  Brass NO 8 Plc, Series 8A, Class A1, 0.98% (3 Month USD 
 
 
 LIBOR + 70 bps), 11/16/66 (144A) 6,203,216 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 41
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COLLATERALIZED MORTGAGE 
 
  OBLIGATIONS — (continued) 
 
628  
Citicorp Mortgage Securities REMIC Pass-Through 
 

 
Certificates Trust, Series 2005-4, Class 2A1,
 
  
5.0%, 7/25/20 
$ 642 
19,447,151(a)  
Connecticut Avenue Securities Trust, Series 2019-HRP1, 
 
  
Class M2, 2.298% (1 Month USD LIBOR + 
 
  
215 bps), 11/25/39 (144A) 
17,413,695 
8,620,653(a)  
Connecticut Avenue Securities Trust, Series 2019-R01, 
 
  
Class 2M2, 2.598% (1 Month USD LIBOR + 
 
  
245 bps), 7/25/31 (144A) 
8,566,672 
3,302,761(a)  
Connecticut Avenue Securities Trust, Series 2020-R01, 
 
  
Class 1M1, 0.948% (1 Month USD LIBOR + 
 
  
80 bps), 1/25/40 (144A) 
3,289,055 
704,434(a)  
Connecticut Avenue Securities Trust, Series 2020-R02, 
 
  
Class 2M1, 0.898% (1 Month USD LIBOR + 
 
  
75 bps), 1/25/40 (144A) 
702,644 
64,888(a)  
CSFB Mortgage-Backed Pass-Through Certificates, 
 
  
Series 2004-AR5, Class 11A2, 0.888% (1 Month USD 
 
  
LIBOR + 74 bps), 6/25/34 
63,871 
755,465(b)  
Deephaven Residential Mortgage Trust, Series 2018-3A, 
 
  
Class A1, 3.789%, 8/25/58 (144A) 
757,831 
766,664(a)  
Deer Creek CLO, Ltd., Series 2017-1A, Class X, 1.272% 
 
  
(3 Month USD LIBOR + 100 bps), 10/20/30 (144A) 
766,654 
3,451,610(a)  
Eagle Re, Ltd., Series 2018-1, Class M1, 1.875% 
 
  
(1 Month USD LIBOR + 170 bps), 11/25/28 (144A) 
3,444,482 
6,292,367(a)  
Eagle Re, Ltd., Series 2019-1, Class M1B, 1.948% 
 
  
(1 Month USD LIBOR + 180 bps), 4/25/29 (144A) 
6,250,901 
11,364,000(a)  
Eagle Re, Ltd., Series 2020-1, Class M1A, 1.048% 
 
  
(1 Month USD LIBOR + 90 bps), 1/25/30 (144A) 
11,277,177 
4,437,547(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2016-C02, Class 1M2, 6.148% (1 Month USD LIBOR + 
 
  
600 bps), 9/25/28 
4,696,010 
9,304,664(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2016-C03, Class 2M2, 6.048% (1 Month USD LIBOR + 
 
  
590 bps), 10/25/28 
9,829,621 
4,610,305(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2017-C01, Class 1M2, 3.698% (1 Month USD LIBOR + 
 
  
355 bps), 7/25/29 
4,742,653 
3,682,149(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2017-C05, Class 1M2, 2.348% (1 Month USD LIBOR + 
 
  
220 bps), 1/25/30 
3,631,263 
10,526,604(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2017-C05, Class 1M2B, 2.348% (1 Month USD LIBOR + 
 
  
220 bps), 1/25/30 
10,441,155 
1,238,764(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2017-C07, Class 1M2A, 2.548% (1 Month USD LIBOR + 
 
  
240 bps), 5/25/30 
1,238,400 
8,783,028(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
  
2018-C04, Class 2M2, 2.698% (1 Month USD LIBOR + 
 
  
255 bps), 12/25/30 
8,626,589 
 
The accompanying notes are an integral part of these financial statements.
42 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
11,106,269(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2018-C05, Class 1M2, 2.498% (1 Month USD LIBOR + 
 
 
 
235 bps), 1/25/31 
$ 10,893,647 
5,115,879(a)  
Fannie Mae Connecticut Avenue Securities, Series 
 
 
 
2018-C06, Class 1M2, 2.148% (1 Month USD LIBOR + 
 
 
 
200 bps), 3/25/31 
5,025,219 
250,806(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
1695, Class EG, 1.212% (1 Month USD LIBOR +
 
 
 
105 bps), 3/15/24 
252,409 
140,921(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2106, Class F, 0.602% (1 Month USD LIBOR +
 
 
 
45 bps), 12/15/28 
141,220 
86,397(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2122, Class FD, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 2/15/29 
84,508 
29,319(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2156, Class FQ, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 5/15/29 
28,906 
166,572(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2186, Class FY, 0.752% (1 Month USD LIBOR +
 
 
 
60 bps), 4/15/28 
167,402 
37,486(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2368, Class AF, 1.102% (1 Month USD LIBOR +
 
 
 
95 bps), 10/15/31 
38,159 
40,323(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2377, Class FE, 0.752% (1 Month USD LIBOR +
 
 
 
60 bps), 11/15/31 
40,622 
105,789(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2411, Class FR, 0.752% (1 Month USD LIBOR +
 
 
 
60 bps), 6/15/31 
106,547 
77,991(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2432, Class FH, 0.852% (1 Month USD LIBOR +
 
 
 
70 bps), 3/15/32 
78,889 
219,077(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2439, Class F, 1.152% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
223,604 
304,847(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2470, Class AF, 1.152% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
311,114 
185,095(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2471, Class FD, 1.152% (1 Month USD LIBOR +
 
 
 
100 bps), 3/15/32 
188,920 
48,943(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2498, Class FQ, 0.752% (1 Month USD LIBOR +
 
 
 
60 bps), 9/15/32 
49,319 
82,621(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2543, Class EF, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 12/15/32 
82,573 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 43
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
359,385(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2551, Class FD, 0.552% (1 Month USD LIBOR +
 
 
 
40 bps), 1/15/33 
$ 361,778 
216,689(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2567, Class FJ, 0.552% (1 Month USD LIBOR +
 
 
 
40 bps), 2/15/33 
216,904 
102,425(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2577, Class FA, 0.702% (1 Month USD LIBOR +
 
 
 
55 bps), 2/15/33 
103,075 
8,199(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2585, Class FD, 0.652% (1 Month USD LIBOR +
 
 
 
50 bps), 12/15/32 
8,236 
114,586(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2614, Class FV, 1.655% (1 Month USD LIBOR +
 
 
 
150 bps), 5/15/33 
118,160 
170,743(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2631, Class FC, 0.552% (1 Month USD LIBOR +
 
 
 
40 bps), 6/15/33 
171,898 
13(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2647, Class XF, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 7/15/21 
13 
103,944(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2711, Class FA, 1.152% (1 Month USD LIBOR +
 
 
 
100 bps), 11/15/33 
105,813 
184,776(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2916, Class NF, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 1/15/35 
184,873 
335,806(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
2976, Class LF, 0.492% (1 Month USD LIBOR +
 
 
 
34 bps), 5/15/35 
337,036 
157,816(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3012, Class FE, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 8/15/35 
157,875 
108,090(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3042, Class PF, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 8/15/35 
108,155 
63,962(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3067, Class FA, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 11/15/35 
64,226 
69,106(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3102, Class FG, 0.452% (1 Month USD LIBOR +
 
 
 
30 bps), 1/15/36 
69,236 
90,092(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3117, Class EF, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 2/15/36 
90,373 
292,909(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3117, Class FE, 0.452% (1 Month USD LIBOR +
 
 
 
30 bps), 2/15/36 
293,333 
 
The accompanying notes are an integral part of these financial statements.
44 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
195,638(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3122, Class FP, 0.452% (1 Month USD LIBOR +
 
 
 
30 bps), 3/15/36 
$ 196,047 
120,635(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3147, Class PF, 0.452% (1 Month USD LIBOR +
 
 
 
30 bps), 4/15/36 
120,883 
297,636(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3173, Class FC, 0.572% (1 Month USD LIBOR +
 
 
 
42 bps), 6/15/36 
299,208 
539,168(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3175, Class FE, 0.462% (1 Month USD LIBOR +
 
 
 
31 bps), 6/15/36 
538,563 
350,051(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3181, Class HF, 0.652% (1 Month USD LIBOR +
 
 
 
50 bps), 7/15/36 
353,679 
16,645(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3191, Class FE, 0.552% (1 Month USD LIBOR +
 
 
 
40 bps), 7/15/36 
16,746 
244,553(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3221, Class FW, 0.572% (1 Month USD LIBOR +
 
 
 
42 bps), 9/15/36 
247,168 
73,577(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3222, Class FN, 0.552% (1 Month USD LIBOR +
 
 
 
40 bps), 9/15/36 
73,928 
250,574(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3239, Class EF, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 11/15/36 
251,692 
130,820(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3239, Class FB, 0.502% (1 Month USD LIBOR +
 
 
 
35 bps), 11/15/36 
131,405 
210,969(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3247, Class FA, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 8/15/36 
211,077 
502,169(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3266, Class F, 0.452% (1 Month USD LIBOR +
 
 
 
30 bps), 1/15/37 
502,577 
184,897(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3307, Class FT, 0.392% (1 Month USD LIBOR +
 
 
 
24 bps), 7/15/34 
184,755 
30,339(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3315, Class F, 0.492% (1 Month USD LIBOR +
 
 
 
34 bps), 5/15/37 
30,461 
435,659(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3373, Class FB, 0.732% (1 Month USD LIBOR +
 
 
 
58 bps), 10/15/37 
441,634 
68,455(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3376, Class FM, 0.772% (1 Month USD LIBOR +
 
 
 
62 bps), 10/15/37 
69,503 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 45
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COLLATERALIZED MORTGAGE 
 
  OBLIGATIONS — (continued) 
 
22,544(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3560, Class FA, 1.402% (1 Month USD LIBOR +
 
  
125 bps), 5/15/37 
$ 23,389 
258,805(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3610, Class FA, 0.852% (1 Month USD LIBOR +
 
  
70 bps), 12/15/39 
262,416 
133,015(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3708, Class PF, 0.502% (1 Month USD LIBOR +
 
  
35 bps), 7/15/40 
133,400 
5,359  
Federal Home Loan Mortgage Corp. REMICS, Series 
 
  
3760, Class KH, 2.0%, 11/15/20 
5,359 
38,998(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3767, Class JF, 0.452% (1 Month USD LIBOR +
 
  
30 bps), 2/15/39 
39,044 
797(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3780, Class FE, 0.552% (1 Month USD LIBOR +
 
  
40 bps), 12/15/20 
797 
73,054(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3784, Class F, 0.552% (1 Month USD LIBOR +
 
  
40 bps), 7/15/23 
72,866 
18,856(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3792, Class DF, 0.552% (1 Month USD LIBOR +
 
  
40 bps), 11/15/40 
18,748 
29,249(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3867, Class FD, 0.502% (1 Month USD LIBOR +
 
  
35 bps), 5/15/41 
29,361 
82,469(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3914, Class LF, 0.352% (1 Month USD LIBOR +
 
  
20 bps), 8/15/26 
82,118 
59,168(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3960, Class FB, 0.452% (1 Month USD LIBOR +
 
  
30 bps), 2/15/30 
59,142 
178,551(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3970, Class GF, 0.452% (1 Month USD LIBOR +
 
  
30 bps), 9/15/26 
178,418 
333,626(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
3982, Class FL, 0.702% (1 Month USD LIBOR +
 
  
55 bps), 12/15/39 
335,467 
142,888(a)  
Federal Home Loan Mortgage Corp. REMICS, Series 
 

 
4056, Class QF, 0.502% (1 Month USD LIBOR +
 
  
35 bps), 12/15/41 
143,248 
135,357(a)  
Federal Home Loan Mortgage Corp. Strips, Series 237, 
 
  
Class F14, 0.552% (1 Month USD LIBOR + 
 
  
40 bps), 5/15/36 
135,349 
116,687(a)  
Federal Home Loan Mortgage Corp. Strips, Series 239, 
 
  
Class F29, 0.402% (1 Month USD LIBOR + 
 
  
25 bps), 8/15/36 
116,625 
504,444(a)  
Federal Home Loan Mortgage Corp. Strips, Series 239, 
 
  
Class F30, 0.452% (1 Month USD LIBOR + 
 
  
30 bps), 8/15/36 
501,854 
 
The accompanying notes are an integral part of these financial statements.
46 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
153,602(a)  
Federal Home Loan Mortgage Corp. Strips, Series 244, 
 
 
 
Class F22, 0.502% (1 Month USD LIBOR + 
 
 
 
35 bps), 12/15/36 
$ 154,049 
6,434(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1991-124, Class FA, 1.048% (1 Month USD LIBOR + 
 
 
 
90 bps), 9/25/21 
6,430 
21,101(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1993-230, Class FA, 0.775% (1 Month USD LIBOR + 
 
 
 
60 bps), 12/25/23 
20,996 
55,423(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1993-247, Class FA, 2.053% (11th District 
 
 
 
Cost of Funds Index + 140 bps), 12/25/23 
56,204 
55,423(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1993-247, Class FE, 1.148% (1 Month USD LIBOR + 
 
 
 
100 bps), 12/25/23 
55,847 
109,037(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1994-40, Class FC, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 3/25/24 
110,101 
16,868(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1997-46, Class FA, 0.65% (1 Month USD LIBOR + 
 
 
 
50 bps), 7/18/27 
16,716 
44,245(a)  
Federal National Mortgage Association REMICS, Series 
 

 
1998-21, Class F, 0.5% (1 Year CMT Index +
 
 
 
35 bps), 3/25/28 
44,012 
2,239(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
1999-49, Class FB, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 3/25/23 
2,236 
36,109(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2000-47, Class FD, 0.698% (1 Month USD LIBOR + 
 
 
 
55 bps), 12/25/30 
36,310 
141,244(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2001-35, Class F, 0.748% (1 Month USD LIBOR +
 
 
 
60 bps), 7/25/31 
142,282 
58,339(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2001-37, Class F, 0.648% (1 Month USD LIBOR +
 
 
 
50 bps), 8/25/31 
58,551 
291,882(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2001-50, Class FQ, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 11/25/31 
294,028 
128,428(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2001-65, Class F, 0.748% (1 Month USD LIBOR +
 
 
 
60 bps), 11/25/31 
129,372 
89,437(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2001-69, Class FA, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/25/31 
90,097 
260,842(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2001-72, Class FB, 1.048% (1 Month USD LIBOR + 
 
 
 
90 bps), 12/25/31 
265,254 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 47
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
67,591(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2001-81, Class FL, 0.8% (1 Month USD LIBOR +
 
 
 
65 bps), 1/18/32 
$ 68,100 
116,645(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2002-1, Class FC, 0.848% (1 Month USD LIBOR +
 
 
 
70 bps), 1/25/32 
117,913 
358,697(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-13, Class FD, 1.048% (1 Month USD LIBOR + 
 
 
 
90 bps), 3/25/32 
363,568 
250,048(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-34, Class FA, 0.65% (1 Month USD LIBOR + 
 
 
 
50 bps), 5/18/32 
251,615 
180,564(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-56, Class FN, 1.148% (1 Month USD LIBOR + 
 
 
 
100 bps), 7/25/32 
184,380 
25,296(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-58, Class FD, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 8/25/32 
25,492 
111,443(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2002-77, Class F, 0.748% (1 Month USD LIBOR +
 
 
 
60 bps), 12/25/32 
112,853 
86,760(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-82, Class FB, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 12/25/32 
87,143 
110,339(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-90, Class FH, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 9/25/32 
110,820 
56,485(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-92, Class FB, 0.798% (1 Month USD LIBOR + 
 
 
 
65 bps), 4/25/30 
56,985 
125,331(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2002-93, Class FH, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 1/25/33 
126,615 
102,304(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-7, Class FA, 0.898% (1 Month USD LIBOR + 
 
 
 
75 bps), 2/25/33 
103,642 
201,212(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2003-8, Class FJ, 0.498% (1 Month USD LIBOR +
 
 
 
35 bps), 2/25/33 
201,125 
308,916(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-31, Class FM, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 4/25/33 
312,124 
140,882(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-42, Class JF, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 5/25/33 
141,528 
76,612(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-49, Class FY, 0.548% (1 Month USD LIBOR + 
 
 
 
40 bps), 6/25/23 
76,570 
 
The accompanying notes are an integral part of these financial statements.
48 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
210,869(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2003-107, Class FD, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 11/25/33 
$ 211,959 
185,052(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2004-52, Class FW, 0.548% (1 Month USD LIBOR + 
 
 
 
40 bps), 7/25/34 
186,076 
53,346(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2004-54, Class FN, 0.598% (1 Month USD LIBOR + 
 
 
 
45 bps), 7/25/34 
53,743 
438,271(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2004-79, Class FM, 0.448% (1 Month USD LIBOR + 
 
 
 
30 bps), 11/25/24 
438,026 
38,154(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2004-91, Class HF, 0.448% (1 Month USD LIBOR + 
 
 
 
30 bps), 11/25/34 
38,214 
193,857(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2005-83, Class KT, 0.448% (1 Month USD LIBOR + 
 
 
 
30 bps), 10/25/35 
194,283 
255,944(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2005-83, Class LF, 0.458% (1 Month USD LIBOR + 
 
 
 
31 bps), 2/25/35 
256,401 
38,714(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-11, Class FB, 0.448% (1 Month USD LIBOR + 
 
 
 
30 bps), 3/25/36 
38,904 
115,522(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-33, Class FH, 0.498% (1 Month USD LIBOR + 
 
 
 
35 bps), 5/25/36 
115,846 
331,154(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-34, Class FA, 0.458% (1 Month USD LIBOR + 
 
 
 
31 bps), 5/25/36 
331,910 
229,020(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-42, Class CF, 0.598% (1 Month USD LIBOR + 
 
 
 
45 bps), 6/25/36 
230,795 
91,414(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-56, Class FC, 0.438% (1 Month USD LIBOR + 
 
 
 
29 bps), 7/25/36 
91,562 
33,984(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-70, Class BF, 0.698% (1 Month USD LIBOR + 
 
 
 
55 bps), 8/25/36 
34,355 
72,044(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2006-82, Class F, 0.718% (1 Month USD LIBOR +
 
 
 
57 bps), 9/25/36 
72,977 
111,604(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-104, Class GF, 0.468% (1 Month USD LIBOR + 
 
 
 
32 bps), 11/25/36 
112,017 
44,711(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2006-115, Class BF, 0.388% (1 Month USD LIBOR + 
 
 
 
24 bps), 12/25/36 
44,667 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 49
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
140,464(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2007-2, Class FT, 0.398% (1 Month USD LIBOR +
 
 
 
25 bps), 2/25/37 
$ 141,045 
168,056(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2007-7, Class FJ, 0.348% (1 Month USD LIBOR +
 
 
 
20 bps), 2/25/37 
167,719 
63,993(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-13, Class FA, 0.398% (1 Month USD LIBOR + 
 
 
 
25 bps), 3/25/37 
63,913 
150,575(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-41, Class FA, 0.548% (1 Month USD LIBOR + 
 
 
 
40 bps), 5/25/37 
151,315 
270,198(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-50, Class FN, 0.388% (1 Month USD LIBOR + 
 
 
 
24 bps), 6/25/37 
269,971 
25,243(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-57, Class FA, 0.378% (1 Month USD LIBOR + 
 
 
 
23 bps), 6/25/37 
25,239 
73,354(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-58, Class FA, 0.398% (1 Month USD LIBOR + 
 
 
 
25 bps), 6/25/37 
73,267 
72,952(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-66, Class FB, 0.548% (1 Month USD LIBOR + 
 
 
 
40 bps), 7/25/37 
73,210 
236,008(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-85, Class FG, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 9/25/37 
238,493 
299,238(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-91, Class FB, 0.748% (1 Month USD LIBOR + 
 
 
 
60 bps), 10/25/37 
303,567 
112,413(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-92, Class OF, 0.718% (1 Month USD LIBOR + 
 
 
 
57 bps), 9/25/37 
113,726 
64,196(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-93, Class FD, 0.698% (1 Month USD LIBOR + 
 
 
 
55 bps), 9/25/37 
64,876 
28,232(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-98, Class FD, 0.598% (1 Month USD LIBOR + 
 
 
 
45 bps), 6/25/37 
28,427 
39,504(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-100, Class YF, 0.698% (1 Month USD LIBOR + 
 
 
 
55 bps), 10/25/37 
40,158 
47,767(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-103, Class AF, 1.148% (1 Month USD LIBOR + 
 
 
 
100 bps), 3/25/37 
49,044 
51,889(a)  
Federal National Mortgage Association REMICS, Series 
 
 
 
2007-110, Class FA, 0.768% (1 Month USD LIBOR + 
 
 
 
62 bps), 12/25/37 
52,607 
 
The accompanying notes are an integral part of these financial statements.
50 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COLLATERALIZED MORTGAGE 
 
  OBLIGATIONS — (continued) 
 
43,000(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2008-6, Class FA, 0.848% (1 Month USD LIBOR + 
 
  
70 bps), 2/25/38 
$ 43,659 
179,012(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2008-88, Class FA, 1.368% (1 Month USD LIBOR + 
 
  
122 bps), 10/25/38 
185,164 
63,573(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2009-113, Class FB, 0.698% (1 Month USD LIBOR + 
 
  
55 bps), 1/25/40 
64,191 
33  
Federal National Mortgage Association REMICS, Series 
 
  
2010-17, Class DE, 3.5%, 6/25/21 
33 
121(a)  
Federal National Mortgage Association REMICS, Series 
 

 
2010-38, Class F, 0.448% (1 Month USD LIBOR +
 
  
30 bps), 4/25/25 
121 
65,803(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2010-43, Class FD, 0.748% (1 Month USD LIBOR + 
 
  
60 bps), 5/25/40 
66,679 
116,506(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2010-43, Class IF, 0.648% (1 Month USD LIBOR + 
 
  
50 bps), 5/25/40 
115,650 
591  
Federal National Mortgage Association REMICS, Series 
 
  
2010-112, Class AE, 2.0%, 10/25/25 
591 
163,636(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2011-19, Class FM, 0.698% (1 Month USD LIBOR + 
 
  
55 bps), 5/25/40 
164,163 
173,298(a)  
Federal National Mortgage Association REMICS, Series 
 
  
2012-40, Class PF, 0.648% (1 Month USD LIBOR + 
 
  
50 bps), 4/25/42 
174,991 
1,473,530(a)  
Federal National Mortgage Association Trust, Series 
 
  
2003-W6, Class F, 0.525% (1 Month USD LIBOR + 
 
  
35 bps), 9/25/42 
1,478,111 
642,944(a)  
Federal National Mortgage Association Trust, Series 
 
  
2005-W3, Class 2AF, 0.368% (1 Month USD LIBOR + 
 
  
22 bps), 3/25/45 
640,509 
49,262(b)  
Federal National Mortgage Association Trust, Series 
 
  
2005-W3, Class 3A, 3.788%, 4/25/45 
53,643 
76,095(b)  
Federal National Mortgage Association Trust, Series 
 
  
2005-W4, Class 3A, 4.382%, 6/25/45 
81,113 
595,181(a)  
Federal National Mortgage Association Whole Loan, 
 
  
Series 2007-W1, Class 1AF1, 0.408% (1 Month USD 
 
  
LIBOR + 26 bps), 11/25/46 
587,901 
3,780,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-DNA4, 
 
  
Class M2, 3.898% (1 Month USD LIBOR + 
 
  
375 bps), 8/25/50 (144A) 
3,825,589 
3,915,673(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA2, 
 
  
Class M1, 1.248% (1 Month USD LIBOR + 
 
  
110 bps), 3/25/50 (144A) 
3,911,759 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 51
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
8,470,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA2, 
 
 
 
Class M2, 3.248% (1 Month USD LIBOR + 
 
 
 
310 bps), 3/25/50 (144A) 
$ 8,342,651 
9,850,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA3, 
 
 
 
Class M2, 3.748% (1 Month USD LIBOR + 
 
 
 
360 bps), 7/25/50 (144A) 
9,899,322 
4,090,000(a)  
Freddie Mac Stacr Remic Trust, Series 2020-HQA4, 
 
 
 
Class M2, 3.302% (1 Month USD LIBOR + 
 
 
 
315 bps), 9/25/50 (144A) 
4,100,948 
14,263,814(a)  
Freddie Mac Stacr Trust, Series 2019-HRP1, Class M2, 
 
 
 
1.548% (1 Month USD LIBOR + 140 bps), 
 
 
 
2/25/49 (144A) 
13,264,194 
1,954,772(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2015-DNA1, Class M3, 3.448% (1 Month 
 
 
 
USD LIBOR + 330 bps), 10/25/27 
1,989,173 
10,973,928(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2015-DNA3, Class M3, 4.848% (1 Month 
 
 
 
USD LIBOR + 470 bps), 4/25/28 
11,413,950 
14,021,936(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA1, Class M3, 5.725% (1 Month 
 
 
 
USD LIBOR + 555 bps), 7/25/28 
14,861,501 
9,595,001(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA2, Class M3, 4.798% (1 Month 
 
 
 
USD LIBOR + 465 bps), 10/25/28 
9,967,440 
14,034,877(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA3, Class M3, 5.148% (1 Month 
 
 
 
USD LIBOR + 500 bps), 12/25/28 
14,475,331 
14,406,074(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-DNA4, Class M3, 3.948% (1 Month 
 
 
 
USD LIBOR + 380 bps), 3/25/29 
14,911,095 
310,506(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2016-HQA3, Class M2, 1.498% (1 Month 
 
 
 
USD LIBOR + 135 bps), 3/25/29 
310,506 
1,400,000(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-DNA2, Class M2, 3.598% (1 Month 
 
 
 
USD LIBOR + 345 bps), 10/25/29 
1,440,529 
3,360,000(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-DNA3, Class M2, 2.648% (1 Month 
 
 
 
USD LIBOR + 250 bps), 3/25/30 
3,389,709 
4,296,051(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HQA1, Class M2, 3.698% (1 Month 
 
 
 
USD LIBOR + 355 bps), 8/25/29 
4,420,780 
6,258,238(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HRP1, Class M2, 2.598% (1 Month 
 
 
 
USD LIBOR + 245 bps), 12/25/42 
5,929,191 
1,030,188(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2017-HRP1, Class M2D, 1.398% (1 Month 
 
 
 
USD LIBOR + 125 bps), 12/25/42 
950,230 
 
The accompanying notes are an integral part of these financial statements.
52 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
7,954,219(a)  
Freddie Mac Structured Agency Credit Risk Debt 
 
 
 
Notes, Series 2018-HQA1, Class M2, 2.448% (1 Month 
 
 
 
USD LIBOR + 230 bps), 9/25/30 
$ 7,824,139 
2,960,733(a)  
Gosforth Funding Plc, Series 2018-1A, Class A1, 0.7% 
 
 
 
(3 Month USD LIBOR + 45 bps), 8/25/60 (144A) 
2,961,900 
100,870(a)  
Government National Mortgage Association, Series 
 

 
2003-7, Class FB, 0.352% (1 Month USD LIBOR +
 
 
 
20 bps), 1/16/33 
100,541 
414,221(a)  
Government National Mortgage Association, Series 
 

 
2005-3, Class FC, 0.402% (1 Month USD LIBOR +
 
 
 
25 bps), 1/16/35 
413,882 
384,950(a)  
Government National Mortgage Association, Series 
 
 
 
2005-16, Class FA, 0.406% (1 Month USD LIBOR + 
 
 
 
25 bps), 2/20/35 
384,631 
130,136(a)  
Government National Mortgage Association, Series 
 
 
 
2008-69, Class FA, 0.656% (1 Month USD LIBOR + 
 
 
 
50 bps), 8/20/38 
130,369 
132,530(a)  
Government National Mortgage Association, Series 
 
 
 
2009-66, Class UF, 1.152% (1 Month USD LIBOR + 
 
 
 
100 bps), 8/16/39 
135,683 
461,082(a)  
Government National Mortgage Association, Series 
 
 
 
2009-88, Class MF, 0.756% (1 Month USD LIBOR + 
 
 
 
60 bps), 7/20/39 
462,038 
100,758(a)  
Government National Mortgage Association, Series 
 
 
 
2009-92, Class FJ, 0.832% (1 Month USD LIBOR + 
 
 
 
68 bps), 10/16/39 
101,971 
2,035,377(a)  
Holmes Master Issuer Plc, Series 2018-2A, Class A2, 
 
 
 
0.695% (3 Month USD LIBOR + 42 bps), 
 
 
 
10/15/54 (144A) 
2,033,275 
12,619,800(a)  
Home Partners of America Trust, Series 2017-1, 
 

 
Class A, 0.968% (1 Month USD LIBOR + 82 bps),
 
 
 
7/17/34 (144A) 
12,573,033 
7,200,000(a)  
Home Partners of America Trust, Series 2017-1, 
 
 
 
Class B, 1.501% (1 Month USD LIBOR + 135 bps), 
 
 
 
7/17/34 (144A) 
7,200,835 
3,610,408(a)  
Home Re, Ltd., Series 2018-1, Class M1, 1.748% 
 
 
 
(1 Month USD LIBOR + 160 bps), 10/25/28 (144A) 
3,564,331 
4,464,414(a)  
Home Re, Ltd., Series 2019-1, Class M1, 1.798% 
 
 
 
(1 Month USD LIBOR + 165 bps), 5/25/29 (144A) 
4,411,837 
896,212(a)  
HomeBanc Mortgage Trust, Series 2005-3, Class A1, 
 
 
 
0.388% (1 Month USD LIBOR + 24 bps), 7/25/35 
896,945 
7,023,906(b)  
JP Morgan Mortgage Trust, Series 2014-IVR6, Class B1, 
 
 
 
2.532%, 7/25/44 (144A) 
7,099,434 
3,400,935(b)  
JP Morgan Mortgage Trust, Series 2017-4, Class A9, 
 
 
 
3.5%, 11/25/48 (144A) 
3,513,878 
2,391,441(a)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class A3, 0.898% (1 Month USD LIBOR + 75 bps), 
 
 
 
4/25/46 (144A) 
2,316,789 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 53
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
8,325,293(b)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class B1, 2.216%, 4/25/46 (144A) 
$ 7,770,946 
7,874,259(b)  
JP Morgan Mortgage Trust, Series 2018-7FRB, 
 
 
 
Class B2, 2.216%, 4/25/46 (144A) 
7,328,534 
1,822,852(a)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class AM, 0.648% (1 Month USD LIBOR + 
 
 
 
50 bps), 5/25/33 (144A) 
1,782,070 
6,807,286(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B1, 0.847%, 5/25/33 (144A) 
6,532,458 
6,345,470(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B2, 0.847%, 5/25/33 (144A) 
6,011,472 
4,891,799(b)  
JP Morgan Seasoned Mortgage Trust, Series 2014-1, 
 
 
 
Class B3, 0.847%, 5/25/33 (144A) 
4,540,679 
437,127(a)  
JP Morgan Trust, Series 2015-1, Class 1A14, 2.035% 
 
 
 
(1 Month USD LIBOR + 125 bps), 12/25/44 (144A) 
441,035 
21,098,984(a)  
LSTAR Securities Investment Trust, Series 2019-2, 
 
 
 
Class A1, 1.655% (1 Month USD LIBOR + 
 
 
 
150 bps), 4/1/24 (144A) 
20,903,411 
23,392,238(a)  
LSTAR Securities Investment, Ltd., Series 2019-3, 
 
 
 
Class A1, 1.655% (1 Month USD LIBOR + 
 
 
 
150 bps), 4/1/24 (144A) 
23,116,184 
24,457,111(a)  
LSTAR Securities Investment, Ltd., Series 2019-4, 
 
 
 
Class A1, 1.655% (1 Month USD LIBOR + 
 
 
 
150 bps), 5/1/24 (144A) 
24,302,985 
11,788,590(a)  
LSTAR Securities Investment, Ltd., Series 2019-5, 
 
 
 
Class A1, 1.655% (1 Month USD LIBOR + 
 
 
 
150 bps), 11/1/24 (144A) 
11,660,631 
12,021(b)  
Merrill Lynch Mortgage Investors Trust, Series 2003-G, 
 
 
 
Class A3, 2.695%, 1/25/29 
11,868 
599,489(a)  
Merrill Lynch Mortgage Investors Trust, Series 2003-H, 
 
 
 
Class A1, 0.788% (1 Month USD LIBOR + 
 
 
 
64 bps), 1/25/29 
588,409 
360,132(a)  
Merrill Lynch Mortgage Investors Trust, Series 2004-B, 
 
 
 
Class A2, 1.117% (6 Month USD LIBOR + 
 
 
 
54 bps), 5/25/29 
351,652 
27,173(a)  
Merrill Lynch Mortgage Investors Trust, Series 2004-C, 
 
 
 
Class A2B, 1.383% (6 Month USD LIBOR + 
 
 
 
100 bps), 7/25/29 
26,378 
100,855(b)  
Merrill Lynch Mortgage Investors Trust, Series 2004-D, 
 
 
 
Class A3, 2.394%, 9/25/29 
98,339 
3,022,081(b)  
Morgan Stanley Residential Mortgage Loan Trust, Series 
 
 
 
2014-1A, Class A1, 2.709%, 6/25/44 (144A) 
3,103,990 
2,564,000(b)  
Morgan Stanley Residential Mortgage Loan Trust, Series 
 
 
 
2014-1A, Class B4, 2.709%, 6/25/44 (144A) 
2,664,200 
5,356,955(a)  
Oaktown Re II, Ltd., Series 2018-1A, Class M1, 1.698% 
 
 
 
(1 Month USD LIBOR + 155 bps), 7/25/28 (144A) 
5,341,062 
3,620,000(a)  
Oaktown Re III, Ltd., Series 2019-1A, Class B1A, 3.648% 
 
 
 
(1 Month USD LIBOR + 350 bps), 7/25/29 (144A) 
3,259,664 
 
The accompanying notes are an integral part of these financial statements.
54 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COLLATERALIZED MORTGAGE 
 
  OBLIGATIONS — (continued) 
 
13,573,000(a)  
Oaktown Re III, Ltd., Series 2019-1A, Class M1B, 
 
  
2.098% (1 Month USD LIBOR + 195 bps), 
 
  
7/25/29 (144A) 
$ 13,367,170 
5,680,000(a)  
Oaktown Re IV Ltd., Series 2020-1A, Class M1B, 
 
  
4.898% (1 Month USD LIBOR + 475 bps), 
 
  
7/25/30 (144A) 
5,680,066 
3,504,177(a)  
OBX Trust, Series 2019-EXP1, Class 2A1A, 1.098% 
 
  
(1 Month USD LIBOR + 95 bps), 1/25/59 (144A) 
3,497,640 
7,950,000(a)  
Pepper I-Prime Trust, Series 2018-2A, Class A1U2, 
 
  
0.631% (1 Month USD LIBOR + 48 bps), 
 
  
10/13/20 (144A) 
7,950,000 
1,734,613(a)  
Pepper Residential Securities Trust, Series 21A, 
 
  
Class A1U, 1.032% (1 Month USD LIBOR + 
 
  
88 bps), 1/16/60 (144A) 
1,729,253 
4,220,679(a)  
Pepper Residential Securities Trust No. 22, Series 22A, 
 
  
Class A1U, 1.156% (1 Month USD LIBOR + 
 
  
100 bps), 6/20/60 (144A) 
4,203,081 
8,585,111(a)  
Pepper Residential Securities Trust No. 25, Series 25A, 
 
  
Class A1U, 1.081% (1 Month USD LIBOR + 
 
  
93 bps), 3/12/61 (144A) 
8,562,223 
1,812,500  
Permanent Master Issuer Plc, Series 2018-1A, 
 
  
Class 1A1, 0.655% (3 Month USD LIBOR + 
 
  
38 bps), 7/15/58 
1,812,261 
741,471(a)  
Radnor Re, Ltd., Series 2018-1, Class M1, 1.548% 
 
  
(1 Month USD LIBOR + 140 bps), 3/25/28 (144A) 
740,111 
4,967,751(a)  
Radnor Re, Ltd., Series 2019-1, Class M1B, 2.098% 
 
  
(1 Month USD LIBOR + 195 bps), 2/25/29 (144A) 
4,889,961 
17,250,000(a)  
Radnor Re, Ltd., Series 2019-2, Class M1B, 1.898% 
 
  
(1 Month USD LIBOR + 175 bps), 6/25/29 (144A) 
17,112,897 
6,000,000(a)  
Radnor Re, Ltd., Series 2020-1, Class M1A, 1.098% 
 
  
(1 Month USD LIBOR + 95 bps), 2/25/30 (144A) 
5,977,835 
7,590,000  
Radnor Re, Ltd., Series 2020-2, Class M1B, 4.146%, 
 
  
(1 Month USD LIBOR + 400 bps), 10/25/30 (144A) 
7,590,000 
2,740,000  
Radnor Re, Ltd., Series 2020-2, Class M1C, 4.746%, 
 
  
(1 Month USD LIBOR + 460 bps), 10/25/30 (144A) 
2,740,000 
1,851,430(a)  
RESI Finance LP, Series 2003-CB1, Class B3, 1.606% 
 
  
(1 Month USD LIBOR + 145 bps), 6/10/35 (144A) 
1,525,521 
4,431,095(a)  
Resimac MBS Trust, Series 2018-2A, Class A1A, 
 
  
1.006% (1 Month USD LIBOR + 85 bps), 
 
  
4/10/50 (144A) 
4,413,746 
810,239(a)  
Resimac Premier, Series 2017-1A, Class A1A, 1.101% 
 
  
(1 Month USD LIBOR + 95 bps), 9/11/48 (144A) 
810,119 
1,944,983(a)  
Resimac Premier, Series 2018-1A, Class A1, 0.956% 
 
  
(1 Month USD LIBOR + 80 bps), 11/10/49 (144A) 
1,942,384 
9,098,421(a)  
Resimac Premier, Series 2019-2A, Class A1, 1.106% 
 
  
(1 Month USD LIBOR + 95 bps), 2/10/51 (144A) 
9,091,743 
4,000,000(a)  
Resimac Premier, Series 2020-1A, Class A1A, 1.209% 
 
  
(1 Month USD LIBOR + 105 bps), 2/7/52 (144A) 
4,000,380 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 55
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COLLATERALIZED MORTGAGE 
 
 
 OBLIGATIONS — (continued) 
 
4,937,421(b)  RMF Buyout Issuance Trust, Series 2020-1, Class A, 
 
 
 2.158%, 2/25/30 (144A) $ 4,942,531 
2,000,000(b)  RMF Buyout Issuance Trust, Series 2020-1, Class M1, 
 
 
 2.332%, 2/25/30 (144A) 2,007,057 
4,515,616(b)  RMF Buyout Issuance Trust, Series 2020-2, Class A, 
 
 
 1.706%, 6/25/30 (144A) 4,521,211 
7,247,796(a)  STACR Trust, Series 2018-HRP1, Class B1, 3.898% 
 
 
 (1 Month USD LIBOR + 375 bps), 4/25/43 (144A) 6,805,917 
5,312,005(a)  STACR Trust, Series 2018-HRP1, Class M2, 1.798% 
 
 
 (1 Month USD LIBOR + 165 bps), 4/25/43 (144A) 5,115,466 
4,474,951(a)  STACR Trust, Series 2018-HRP2, Class M2, 1.398% 
 
 
 (1 Month USD LIBOR + 125 bps), 2/25/47 (144A) 4,349,716 
17,605,000(a)  STACR Trust, Series 2018-HRP2, Class M3, 2.548% 
 
 
 (1 Month USD LIBOR + 240 bps), 2/25/47 (144A) 16,795,740 
7,500,000(a)  Starwood Waypoint Homes Trust, Series 2017-1, 
 
 
 Class B, 1.322% (1 Month USD LIBOR + 
 
 
 117 bps), 1/17/35 (144A) 7,477,679 
10,066,417(a)  Towd Point HE Trust, Series 2019-HE1, Class A1, 
 
 
 1.048% (1 Month USD LIBOR + 90 bps), 
 
 
 4/25/48 (144A) 10,027,884 
6,344,757(a)  Towd Point HE Trust, Series 2019-HE1, Class M1, 
 
 
 1.248% (1 Month USD LIBOR + 110 bps), 
 
 
 
4/25/48 (144A) 
6,216,675 
 
 TOTAL COLLATERALIZED MORTGAGE OBLIGATIONS 
 
 
 
(Cost $703,886,191) 
$ 687,457,356 

 COMMERCIAL MORTGAGE-BACKED 
 
 SECURITIES — 11.4% of Net Assets 
 
1,542,078(a)  AREIT Trust, Series 2018-CRE2, Class A, 1.132% 
 
 
 (1 Month USD LIBOR + 98 bps), 11/14/35 (144A) $ 1,520,988 
12,500,000(a)  Austin Fairmont Hotel Trust, Series 2019-FAIR, 
 
 
 Class E, 2.402% (1 Month USD LIBOR + 225 bps), 
 
 
 9/15/32 (144A) 10,900,011 
8,000,000(a)  BAMLL Commercial Mortgage Securities Trust, 
 

 
Series 2019-RLJ, Class C, 1.752% (1 Month USD
 
 
 LIBOR + 160 bps), 4/15/36 (144A) 7,554,882 
978,591(a)  Bancorp Commercial Mortgage Trust, Series 
 
 
 2018-CRE4, Class A, 1.052% (1 Month USD LIBOR + 
 
 
 90 bps), 9/15/35 (144A) 968,596 
13,500,000(a)  BHP Trust, Series 2019-BXHP, Class D, 1.924% 
 
 
 (1 Month USD LIBOR + 177 bps), 8/15/36 (144A) 12,412,259 
7,750,000(a)  BTH-13 Mortgage Backed Securities Trust, Series 
 
 
 2018-13, Class A, 2.655% (1 Month USD LIBOR + 
 
 
 250 bps), 8/18/21 (144A) 7,694,670 
5,700,000(a)  BTH-16 Mortgage-Backed Securities Trust, Series 
 
 
 2018-16, Class A, 2.655% (1 Month USD LIBOR + 
 
 
 250 bps), 8/4/21 (144A) 5,514,174 
 
The accompanying notes are an integral part of these financial statements.
56 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COMMERCIAL MORTGAGE-BACKED 
 
 
 SECURITIES — (continued) 
 
7,625,000(a)  
BTH-21 Mortgage-Backed Securities Trust, Series 
 
 
 
2018-21, Class A, 2.655% (1 Month USD LIBOR + 
 
 
 
250 bps), 10/7/21 (144A) 
$ 7,571,273 
14,500,000(a)  
BTH-25 Mortgage-Backed Securities Trust, Series 
 
 
 
2019-25, Class A, 2.656% (1 Month USD LIBOR + 
 
 
 
250 bps), 2/18/21 (144A) 
14,393,714 
5,884,925(a)  
BTH-3 Mortgage-Backed Securities Trust, Series 
 

 
2018-3, Class A, 2.655% (1 Month USD LIBOR +
 
 
 
250 bps), 7/8/21 
5,682,381 
5,810,000(a)  
BX Commercial Mortgage Trust, Series 2018-IND, 
 
 
 
Class D, 1.452% (1 Month USD LIBOR + 130 bps), 
 
 
 
11/15/35 (144A) 
5,766,228 
15,483,047(a)  
BX Commercial Mortgage Trust, Series 2019-XL, 
 
 
 
Class G, 2.452% (1 Month USD LIBOR + 230 bps), 
 
 
 
10/15/36 (144A) 
15,231,409 
9,300,000(a)  
BX Trust, Series 2019-ATL, Class B, 1.539% (1 Month 
 
 
 
USD LIBOR + 139 bps), 10/15/36 (144A) 
8,698,419 
8,000,000(a)  
BXP Trust, Series 2017-CQHP, Class B, 1.252% (1 Month 
 
 
 
USD LIBOR + 110 bps), 11/15/34 (144A) 
7,462,407 
2,171,167(a)  
CG-CCRE Commercial Mortgage Trust, Series 2014-FL1, 
 
 
 
Class B, 1.302% (1 Month USD LIBOR + 
 
 
 
115 bps), 6/15/31 (144A) 
2,129,443 
722,572(a)  
CG-CCRE Commercial Mortgage Trust, Series 2014-FL2, 
 
 
 
Class A, 2.006% (1 Month USD LIBOR + 
 
 
 
185 bps), 11/15/31 (144A) 
676,419 
10,000,000(a)  
CGDB Commercial Mortgage Trust, Series 2019-MOB, 
 
 
 
Class C, 1.602% (1 Month USD LIBOR + 
 
 
 
145 bps), 11/15/36 (144A) 
9,875,453 
5,700,000(a)  
CGMS Commercial Mortgage Trust, Series 2017-MDRC, 
 
 
 
Class C, 1.452% (1 Month USD LIBOR + 
 
 
 
130 bps), 7/15/30 (144A) 
5,372,079 
14,935,551(a)  
CHC Commercial Mortgage Trust, Series 2019-CHC, 
 
 
 
Class C, 1.902% (1 Month USD LIBOR + 175 bps), 
 
 
 
6/15/34 (144A) 
13,943,157 
9,500,000(a)  
CHT Mortgage Trust, Series 2017-CSMO, Class C, 
 
 
 
1.652% (1 Month USD LIBOR + 150 bps), 
 
 
 
11/15/36 (144A) 
9,071,062 
8,750,000(a)  
Citigroup Commercial Mortgage Trust, Series 
 
 
 
2019-SST2, Class B, 1.252% (1 Month USD LIBOR + 
 
 
 
110 bps), 12/15/36 (144A) 
8,518,938 
5,500,000(a)  
Citigroup Commercial Mortgage Trust, Series 
 
 
 
2019-SST2, Class C, 1.452% (1 Month USD LIBOR + 
 
 
 
130 bps), 12/15/36 (144A) 
5,302,014 
6,000,000(a)  
CLNY Trust, Series 2019-IKPR, Class B, 1.63% (1 Month 
 
 
 
USD LIBOR + 148 bps), 11/15/38 (144A) 
5,610,724 
2,000,000(a)  
CLNY Trust, Series 2019-IKPR, Class E, 2.873% (1 Month 
 
 
 
USD LIBOR + 272 bps), 11/15/38 (144A) 
1,689,367 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 57
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COMMERCIAL MORTGAGE-BACKED 
 
 
 SECURITIES — (continued) 
 
6,750,000(a)  
Credit Suisse Commercial Mortgage Securities Corp., 
 
 
 
Series 2019-SKLZ, Class B, 2.052% (1 Month USD 
 
 
 
LIBOR + 190 bps), 1/15/34 (144A) 
$ 6,447,722 
10,000,000(a)  
Credit Suisse Mortgage Capital Certificates, Series 
 
 
 
2019-ICE4, Class E, 2.302% (1 Month USD LIBOR + 
 
 
 
215 bps), 5/15/36 (144A) 
9,861,987 
19,750,000(a)  
Exantas Capital Corp., Series 2020-RSO8, Class A, 
 
 
 
1.301% (1 Month USD LIBOR + 115 bps), 
 
 
 
3/15/35 (144A) 
19,487,284 
326,195(a)  
FREMF Mortgage Trust, Series 2014-KF03, Class B, 
 
 
 
4.657% (1 Month USD LIBOR + 450 bps), 
 
 
 
1/25/21 (144A) 
325,551 
1,715,812(a)  
FREMF Mortgage Trust, Series 2014-KF05, Class B, 
 
 
 
4.157% (1 Month USD LIBOR + 400 bps), 
 
 
 
9/25/22 (144A) 
1,697,616 
2,930,828(a)  
FREMF Mortgage Trust, Series 2014-KS02, Class B, 
 
 
 
5.157% (1 Month USD LIBOR + 500 bps), 
 
 
 
8/25/23 (144A) 
2,648,809 
3,907,816(a)  
FREMF Mortgage Trust, Series 2018-KI01, Class B, 
 
 
 
2.607% (1 Month USD LIBOR + 245 bps), 
 
 
 
9/25/22 (144A) 
3,869,659 
2,598,010(a)  
GPMT, Ltd., Series 2018-FL1, Class A, 1.056% (1 Month 
 
 
 
USD LIBOR + 90 bps), 11/21/35 (144A) 
2,585,035 
3,250,000(a)  
GPMT, Ltd., Series 2018-FL1, Class AS, 1.356% (1 Month 
 
 
 
USD LIBOR + 120 bps), 11/21/35 (144A) 
3,185,081 
8,000,000(a)  
Great Wolf Trust, Series 2019-WOLF, Class D, 2.085% 
 
 
 
(1 Month USD LIBOR + 193 bps), 12/15/36 (144A) 
7,323,121 
9,400,000(b)  
GS Mortgage Securities Corp. Trust, Series 2016-RENT, 
 
 
 
Class E, 4.202%, 2/10/29 (144A) 
9,300,302 
3,500,000(a)  
GS Mortgage Securities Corp. Trust, Series 2017-STAY, 
 
 
 
Class B, 1.502% (1 Month USD LIBOR + 
 
 
 
135 bps), 7/15/32 (144A) 
3,437,369 
10,900,000(a)  
GS Mortgage Securities Corp. Trust, Series 2018-TWR, 
 
 
 
Class A, 1.052% (1 Month USD LIBOR + 
 
 
 
90 bps), 7/15/31 (144A) 
10,656,328 
11,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2019-70P, 
 
 
 
Class D, 1.902% (1 Month USD LIBOR + 
 
 
 
175 bps), 10/15/36 (144A) 
10,172,317 
7,400,000(a)  
GS Mortgage Securities Corp. Trust, Series 2019-SMP, 
 
 
 
Class D, 2.102% (1 Month USD LIBOR + 
 
 
 
195 bps), 8/15/32 (144A) 
6,615,403 
10,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2020-DUNE, 
 
 
 
Class A, 1.252% (1 Month USD LIBOR + 
 
 
 
110 bps), 12/15/36 (144A) 
9,647,885 
9,000,000(a)  
GS Mortgage Securities Corp. Trust, Series 2020-DUNE, 
 
 
 
Class E, 2.652% (1 Month USD LIBOR + 
 
 
 
250 bps), 12/15/36 (144A) 
7,739,721 
4,300,000(a)  
GS Mortgage Securities Trust, Series 2018-HART, 
 
 
 
Class A, 1.242% (1 Month USD LIBOR + 109 bps), 
 
 
 
10/15/31 (144A) 
4,225,254 
 
The accompanying notes are an integral part of these financial statements.
58 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COMMERCIAL MORTGAGE-BACKED 
 
  SECURITIES — (continued) 
 
9,729,000(a)  
GS Mortgage Securities Trust, Series 2018-HART, 
 
  
Class B, 1.452% (1 Month USD LIBOR + 130 bps), 
 
  
10/15/31 (144A) 
$ 9,188,703 
8,195,929(a)  
HPLY Trust, Series 2019-HIT, Class C, 1.752% (1 Month 
 
  
USD LIBOR + 160 bps), 11/15/36 (144A) 
7,723,188 
4,665,000(a)  
InTown Hotel Portfolio Trust, Series 2018-STAY, 
 

 
Class A, 0.852% (1 Month USD LIBOR + 70 bps),
 
  
1/15/33 (144A) 
4,557,423 
4,230,000(a)  
InTown Hotel Portfolio Trust, Series 2018-STAY, 
 
  
Class B, 1.202% (1 Month USD LIBOR + 105 bps), 
 
  
1/15/33 (144A) 
4,114,016 
11,900,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2017-FL11, Class B, 1.252% (1 Month 
 
  
USD LIBOR + 110 bps), 10/15/32 (144A) 
11,308,869 
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) 
6,507,063 
2,800,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2018-WPT, Class BFL, 1.409% (1 Month 
 
  
USD LIBOR + 125 bps), 7/5/33 (144A) 
2,747,912 
4,000,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2018-WPT, Class CFL, 1.809% (1 Month 
 
  
USD LIBOR + 165 bps), 7/5/33 (144A) 
3,862,536 
3,600,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2019-BKWD, Class C, 1.752% (1 Month 
 
  
USD LIBOR + 160 bps), 9/15/29 (144A) 
3,435,106 
1,650,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2019-BKWD, Class E, 2.752% (1 Month 
 
  
USD LIBOR + 260 bps), 9/15/29 (144A) 
1,461,410 
10,300,000(a)  
JP Morgan Chase Commercial Mortgage Securities 
 
  
Trust, Series 2019-MFP, Class E, 2.312% (1 Month 
 
  
USD LIBOR + 216 bps), 7/15/36 (144A) 
9,667,526 
194,615  
JPMBB Commercial Mortgage Securities Trust, Series 
 
  
2014-C19, Class A2, 3.046%, 4/15/47 
195,277 
8,050,000(a)  
MBRT, Series 2019-MBR, Class B, 1.302% (1 Month USD 
 
  
LIBOR + 115 bps), 11/15/36 (144A) 
7,609,755 
20,000,000(a)  
MF1, Ltd., Series 2019-FL2, Class A, 1.278% (1 Month 
 
  
USD LIBOR + 113 bps), 12/25/34 (144A) 
19,662,660 
7,286,627(a)  
MMFL Re-REMIC Trust, Series 2019-1, Class A, 1.548% 
 
  
(1 Month USD LIBOR + 140 bps), 1/28/24 (144A) 
6,721,696 
1,757,940(b)  
Morgan Stanley Capital I Trust, Series 2007-T25, 
 
  
Class AJ, 5.574%, 11/12/49 
1,791,005 
8,500,000(a)  
Morgan Stanley Capital I Trust, Series 2017-ASHF, 
 
  
Class B, 1.402% (1 Month USD LIBOR + 
 
  
125 bps), 11/15/34 (144A) 
7,979,621 
8,250,000(a)  
Morgan Stanley Capital I Trust, Series 2017-CLS, 
 
  
Class C, 1.152% (1 Month USD LIBOR + 
 
  
100 bps), 11/15/34 (144A) 
8,209,737 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 59
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 COMMERCIAL MORTGAGE-BACKED 
 
 
 SECURITIES — (continued) 
 
9,610,247(a)  
Morgan Stanley Capital I Trust, Series 2018-BOP, 
 
 
 
Class B, 1.402% (1 Month USD LIBOR + 
 
 
 
125 bps), 8/15/33 (144A) 
$ 9,140,237 
7,275,000(a)  
Morgan Stanley Capital I Trust, Series 2019-NUGS, 
 
 
 
Class D, 3.3% (1 Month USD LIBOR + 
 
 
 
180 bps), 12/15/36 (144A) 
6,825,428 
9,709,619(a)  
Motel 6 Trust, Series 2017-MTL6, Class C, 1.552% 
 
 
 
(1 Month USD LIBOR + 140 bps), 8/15/34 (144A) 
9,465,954 
5,220,000(a)  
MTRO Commercial Mortgage Trust, Series 2019-TECH, 
 
 
 
Class C, 1.452% (1 Month USD LIBOR + 
 
 
 
130 bps), 12/15/33 (144A) 
5,106,889 
3,662,523(a)  
Natixis Commercial Mortgage Securities Trust, Series 
 

 
2018-FL1, Class MCR1, 2.512% (1 Month USD
 
 
 
LIBOR + 235 bps), 6/15/35 (144A) 
3,447,383 
11,500,000(a)  
Natixis Commercial Mortgage Securities Trust, Series 
 
 
 
2019-MILE, Class B, 1.952% (1 Month USD LIBOR 
 
 
 
+ 180 bps), 7/15/36 (144A) 
11,157,048 
277,157(a)  
NCUA Guaranteed Notes Trust, Series 2011-C1, 
 
 
 
Class 2A, 0.685% (1 Month USD LIBOR + 
 
 
 
53 bps), 3/9/21 
276,983 
1,070,130(a)  
RETL, Series 2019-RVP, Class A, 1.302% (1 Month USD 
 
 
 
LIBOR + 115 bps), 3/15/36 (144A) 
1,070,171 
6,908,048(a)  
SLIDE, Series 2018-FUN, Class B, 1.402% (1 Month USD 
 
 
 
LIBOR + 125 bps), 6/15/31 (144A) 
6,456,642 
1,547,912(b)  
Sutherland Commercial Mortgage Loans, Series 
 
 
 
2017-SBC6, Class A, 3.192%, 5/25/37 (144A) 
1,537,843 
3,447,172(b)  
Sutherland Commercial Mortgage Loans, Series 
 
 
 
2018-SBC7, Class A, 4.72%, 5/25/39 (144A) 
3,453,225 
4,374,433(a)  
Tharaldson Hotel Portfolio Trust, Series 2018-THL, 
 
 
 
Class C, 1.509% (1 Month USD LIBOR + 
 
 
 
135 bps), 11/11/34 (144A) 
4,001,303 
10,150,000(a)  
VMC Finance LLC, Series 2018-FL2, Class B, 1.501% 
 
 
 
(1 Month USD LIBOR + 135 bps), 10/15/35 (144A) 
9,554,944 
2,164,933(b)  
WaMu Commercial Mortgage Securities Trust, Series 
 
 
 
2006-SL1, Class C, 3.153%, 11/23/43 (144A) 
2,166,813 
12,800,000(a)  
Wells Fargo Commercial Mortgage Trust, Series 
 
 
 
2017-SMP, Class C, 1.352% (1 Month USD LIBOR + 
 
 
 
120 bps), 12/15/34 (144A) 
11,185,838 
17,500,000(a)  
XCAL Mortgage Trust, Series 2019-1, Class A, 4.4% 
 
 
 
(1 Month USD LIBOR + 225 bps), 11/6/21 (144A) 
17,249,650 
14,200,000(a)  
XCALI Mortgage Trust, Series 2020-1, Class A, 4.05% 
 
 
 
(1 Month USD LIBOR + 240 bps), 1/22/23 (144A) 
13,999,201 
13,500,000(a)  
XCALI Mortgage Trust, Series 2020-2, Class A, 4.05% 
 
 
 
(1 Month USD LIBOR + 200 bps), 2/7/23 (144A) 
13,217,383 
 
 TOTAL COMMERCIAL MORTGAGE-BACKED SECURITIES 
 
 
 
(Cost $563,533,334) 
$ 538,842,949 
 
The accompanying notes are an integral part of these financial statements.
60 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 CORPORATE BONDS — 27.2% of Net Assets 
 
 
 Auto Manufacturers — 2.0% 
 
7,775,000(a)  American Honda Finance Corp., 0.467% (3 Month 
 
 
 USD LIBOR + 21 bps), 2/12/21 $ 7,779,144 
3,960,000(a)  American Honda Finance Corp., 0.613% (3 Month 
 
 
 USD LIBOR + 37 bps), 5/10/23 3,954,159 
9,190,000(a)  American Honda Finance Corp., 0.773% (3 Month 
 
 
 USD LIBOR + 54 bps), 6/27/22 9,228,587 
2,015,000(a)  Ford Motor Credit Co. LLC, 1.146% (3 Month USD 
 
 
 LIBOR + 88 bps), 10/12/21 1,935,857 
6,750,000(a)  Nissan Motor Acceptance Corp., 0.77% (3 Month 
 
 
 USD LIBOR + 52 bps), 3/15/21 (144A) 6,718,773 
6,020,000  Nissan Motor Acceptance Corp., 2.55%, 3/8/21 (144A) 6,051,251 
8,889,000(a)  PACCAR Financial Corp., 0.503% (3 Month USD 
 
 
 LIBOR + 26 bps), 5/10/21 8,899,680 
18,160,000(a)  Toyota Motor Credit Corp., 0.546% (3 Month USD 
 
 
 LIBOR + 28 bps), 4/13/21 18,183,516 
14,185,000(a)  Volkswagen Group of America Finance LLC, 1.024% 
 
 
 (3 Month USD LIBOR + 77 bps), 11/13/20 (144A) 14,194,173 
14,245,000(a)  Volkswagen Group of America Finance LLC, 1.083% 
 
 
 (3 Month USD LIBOR + 86 bps), 9/24/21 (144A) 14,298,785 
5,550,000(a)  Volkswagen Group of America Finance LLC, 1.197% 
 
 
 (3 Month USD LIBOR + 94 bps), 11/12/21 (144A) 5,577,150 
 
 Total Auto Manufacturers $ 96,821,075 
 
 Automobiles & Components — 0.2% 
 
11,520,000  General Motors Finland, Inc., 4.375%, 9/25/21 $ 11,884,844 
 
 Total Automobiles & Components $ 11,884,844 
 
 Banks — 14.0% 
 
4,360,000(a)  ABN AMRO Bank NV, 0.821% (3 Month USD LIBOR + 
 
 
 57 bps), 8/27/21 (144A) $ 4,377,809 
5,650,000  ABN AMRO Bank NV, 3.4%, 8/27/21 (144A) 5,804,556 
23,289,000(a)  Bank of America Corp., 1.038% (3 Month USD LIBOR + 
 
 
 79 bps), 3/5/24 23,389,734 
11,209,000(a)  Bank of America Corp., 1.451% (3 Month USD LIBOR + 
 
 
 118 bps), 10/21/22 11,325,349 
2,082,000(a)  Bank of America Corp., 1.692% (3 Month USD LIBOR + 
 
 
 142 bps), 4/19/21 2,097,592 
3,185,000(a)  Bank of Montreal, 0.754% (SOFRRATE + 
 
 
 68 bps), 3/10/23 3,199,842 
3,138,000(a)  Bank of Nova Scotia, 0.712% (3 Month USD LIBOR + 
 
 
 44 bps), 4/20/21 3,145,391 
3,069,000  Bank of Nova Scotia, 2.5%, 1/8/21 3,087,666 
2,620,000(a)  Banque Federative du Credit Mutuel SA, 1.232% 
 
 
 (3 Month USD LIBOR + 96 bps), 7/20/23 (144A) 2,652,185 
12,010,000(a)  Banque Federative du Credit Mutuel SA, 1.002% 
 
 
 (3 Month USD LIBOR + 73 bps), 7/20/22 (144A) 12,106,975 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 61
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Banks — (continued) 
 
12,008,000(a)  
Barclays Plc, 1.71% (3 Month USD LIBOR + 
 
 
 
143 bps), 2/15/23 
$ 12,067,760 
6,050,000(a)  
Barclays Plc, 1.898% (3 Month USD LIBOR + 
 
 
 
163 bps), 1/10/23 
6,093,526 
18,956,000(a)  
BPCE SA, 1.476% (3 Month USD LIBOR + 122 bps), 
 
 
 
5/22/22 (144A) 
19,164,654 
9,550,000(a)  
Capital One NA, 1.063% (3 Month USD LIBOR + 
 
 
 
82 bps), 8/8/22 
9,611,954 
5,890,000  
Capital One NA, 2.95%, 7/23/21 
6,004,869 
9,095,000(a)  
Citibank NA, 0.607% (3 Month USD LIBOR + 
 
 
 
35 bps), 2/12/21 
9,103,304 
16,729,000(a)  
Citigroup, Inc., 1.205% (3 Month USD LIBOR + 
 
 
 
96 bps), 4/25/22 
16,891,940 
11,141,000(a)  
Citigroup, Inc., 1.318% (3 Month USD LIBOR + 
 
 
 
107 bps), 12/8/21 
11,243,098 
1,620,000(a)  
Citigroup, Inc., 1.441% (3 Month USD LIBOR + 
 
 
 
119 bps), 8/2/21 
1,634,036 
12,180,000(a)  
Citigroup, Inc., 1.6% (3 Month USD LIBOR + 
 
 
 
138 bps), 3/30/21 
12,255,954 
12,733,000  
Citigroup, Inc., 2.7%, 3/30/21 
12,883,504 
2,375,000(a)  
Cooperatieve Rabobank UA, 0.675% (3 Month USD 
 
 
 
LIBOR + 43 bps), 4/26/21 
2,380,271 
2,350,000(a)  
Cooperatieve Rabobank UA, 0.753% (3 Month USD 
 
 
 
LIBOR + 48 bps), 1/10/23 
2,362,366 
5,700,000(a)  
Cooperatieve Rabobank UA, 1.103% (3 Month USD 
 
 
 
LIBOR + 83 bps), 1/10/22 
5,747,361 
9,410,000(a)  
Credit Suisse Group AG, 1.449% (3 Month USD LIBOR + 
 
 
 
120 bps), 12/14/23 (144A) 
9,492,726 
14,947,000(a)  
Credit Suisse Group Funding Guernsey, Ltd., 2.562% 
 
 
 
(3 Month USD LIBOR + 229 bps), 4/16/21 
15,120,176 
16,950,000  
Credit Suisse Group Funding Guernsey, Ltd., 
 
 
 
3.125%, 12/10/20 
17,038,140 
4,002,000  
Danske Bank, Inc., 2.7%, 3/2/22 (144A) 
4,122,158 
1,845,000  
Discover Bank, 3.2%, 8/9/21 
1,882,125 
10,300,000(a)  
DNB Bank ASA, 0.861% (3 Month USD LIBOR + 
 
 
 
62 bps), 12/2/22 (144A) 
10,376,898 
10,265,000(a)  
Federation des Caisses Desjardins du Quebec, 0.598% 
 
 
 
(3 Month USD LIBOR + 33 bps), 10/30/20 (144A) 
10,268,022 
5,000,000(a)  
Goldman Sachs Group, Inc., 1.006% (3 Month USD 
 
 
 
LIBOR + 75 bps), 2/23/23 
5,016,191 
4,425,000(a)  
Goldman Sachs Group, Inc., 1.355% (3 Month USD 
 
 
 
LIBOR + 111 bps), 4/26/22 
4,443,304 
1,000,000(a)  
Goldman Sachs Group, Inc., 1.45% (3 Month USD 
 
 
 
LIBOR + 117 bps), 11/15/21 
1,001,234 
11,230,000(a)  
Goldman Sachs Group, Inc., 1.605% (3 Month USD 
 
 
 
LIBOR + 136 bps), 4/23/21 
11,294,751 
 
The accompanying notes are an integral part of these financial statements.
62 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Banks — (continued) 
 
5,880,000(a)  
Goldman Sachs Group, Inc., 2.02% (3 Month USD 
 
 
 
LIBOR + 177 bps), 2/25/21 
$ 5,920,833 
2,725,000(a)  
JPMorgan Chase & Co., 0.843% (3 Month USD LIBOR + 
 
 
 
61 bps), 6/18/22 
2,733,241 
11,800,000(a)  
JPMorgan Chase & Co., 0.986% (3 Month USD LIBOR + 
 
 
 
73 bps), 4/23/24 
11,882,004 
18,025,000(a)  
JPMorgan Chase & Co., 1.348% (3 Month USD LIBOR + 
 
 
 
110 bps), 6/7/21 
18,140,160 
2,905,000(a)  
KeyBank NA, 0.911% (3 Month USD LIBOR + 
 
 
 
66 bps), 2/1/22 
2,923,001 
8,000,000(a)  
Macquarie Bank, Ltd., 0.699% (3 Month USD LIBOR + 
 
 
 
45 bps), 8/6/21 (144A) 
8,025,266 
2,968,000(a)  
Mitsubishi UFJ Financial Group, Inc., 0.895% (3 Month 
 
 
 
USD LIBOR + 65 bps), 7/26/21 
2,979,471 
3,000,000(a)  
Mitsubishi UFJ Financial Group, Inc., 0.948% (3 Month 
 
 
 
USD LIBOR + 70 bps), 3/7/22 
3,019,828 
25,302,000(a)  
Mitsubishi UFJ Financial Group, Inc., 1.035% (3 Month 
 
 
 
USD LIBOR + 79 bps), 7/25/22 
25,494,457 
6,295,000(a)  
Mizuho Financial Group, Inc., 1.099% (3 Month USD 
 
 
 
LIBOR + 85 bps), 9/13/23 
6,327,545 
7,505,000(a)  
Mizuho Financial Group, Inc., 1.13% (3 Month USD 
 
 
 
LIBOR + 88 bps), 9/11/22 
7,576,089 
14,679,000(a)  
Mizuho Financial Group, Inc., 1.196% (3 Month USD 
 
 
 
LIBOR + 94 bps), 2/28/22 
14,825,069 
12,580,000(a)  
Morgan Stanley, 1.188% (3 Month USD LIBOR + 
 
 
 
93 bps), 7/22/22 
12,638,294 
12,403,000(a)  
Morgan Stanley, 1.452% (3 Month USD LIBOR + 
 
 
 
118 bps), 1/20/22 
12,439,122 
12,114,000(a)  
PNC Bank NA, 0.708% (3 Month USD LIBOR + 
 
 
 
45 bps), 7/22/22 
12,147,315 
4,499,000(a)  
PNC Bank NA, 0.745% (3 Month USD LIBOR + 
 
 
 
50 bps), 7/27/22 
4,522,983 
3,175,000  
PNC Bank NA, 2.45%, 11/5/20 
3,175,735 
3,878,000  
PNC Bank NA, 2.5%, 1/22/21 
3,897,315 
9,000,000(a)  
Royal Bank of Canada, 0.645% (3 Month USD LIBOR + 
 
 
 
40 bps), 1/25/21 
9,011,224 
445,000(a)  
Royal Bank of Canada, 0.658% (3 Month USD LIBOR + 
 
 
 
39 bps), 4/30/21 
445,948 
12,310,000(a)  
Royal Bank of Canada, 0.74% (3 Month USD LIBOR + 
 
 
 
47 bps), 4/29/22 
12,373,470 
5,502,000  
Royal Bank of Canada, 2.15%, 10/26/20 
5,509,373 
681,000  
Royal Bank of Canada, 2.35%, 10/30/20 
682,126 
4,800,000  
Royal Bank of Canada, 3.35%, 10/22/21 (144A) 
4,950,048 
15,252,000(a)  
Skandinaviska Enskilda Banken AB, 0.894% (3 Month 
 
 
 
USD LIBOR + 65 bps), 12/12/22 (144A) 
15,375,191 
7,040,000  
Skandinaviska Enskilda Banken AB, 2.625%, 
 
 
 
11/17/20 (144A) 
7,060,909 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 63
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Banks — (continued) 
 
13,625,000  
Skandinaviska Enskilda Banken AB, 3.25%, 
 
  
5/17/21 (144A) 
$ 13,867,334 
4,232,000(a)  
Sumitomo Mitsui Financial Group, Inc., 1.012% 
 
  
(3 Month USD LIBOR + 74 bps), 10/18/22 
4,260,193 
21,084,000(a)  
Sumitomo Mitsui Financial Group, Inc., 1.046% 
 
  
(3 Month USD LIBOR + 78 bps), 7/12/22 
21,241,391 
5,265,000(a)  
Toronto-Dominion Bank, 0.776% (3 Month USD 
 
  
LIBOR + 53 bps), 12/1/22 
5,316,068 
1,000,000(a)  
Toronto-Dominion Bank, 0.912% (3 Month USD 
 
  
LIBOR + 64 bps), 7/19/23 
1,011,271 
1,035,000(a)  
Toronto-Dominion Bank, 1.276% (3 Month USD 
 
  
LIBOR + 100 bps), 4/7/21 
1,040,130 
25,014,000(a)  
Truist Bank, 0.87% (3 Month USD LIBOR + 
 
  
59 bps), 5/17/22 
25,177,029 
4,870,000(a)  
UBS AG, 0.726% (3 Month USD LIBOR + 
 
  
48 bps), 12/1/20 (144A) 
4,871,665 
10,670,000(a)  
UBS Group AG, 1.781% (3 Month USD LIBOR + 
 
  
153 bps), 2/1/22 (144A) 
10,854,139 
2,450,000  
UBS Group AG, 3.0%, 4/15/21 (144A) 
2,484,476 
2,025,000(a)  
US Bancorp, 0.904% (3 Month USD LIBOR + 
 
  
64 bps), 1/24/22 
2,038,780 
1,315,000(a)  
US Bank NA, 0.565% (3 Month USD LIBOR + 
 
  
32 bps), 4/26/21 
1,316,584 
12,490,000(a)  
US Bank NA, 0.696% (3 Month USD LIBOR + 
 
  
44 bps), 5/23/22 
12,550,144 
15,234,000(a)  
Wells Fargo & Co., 1.183% (3 Month USD LIBOR + 
 
  
93 bps), 2/11/22 
15,271,459 
14,665,000(a)  
Wells Fargo & Co., 1.27% (3 Month USD LIBOR + 
 
  
103 bps), 7/26/21 
14,772,055 
3,350,000(a)  
Wells Fargo & Co., 1.591% (3 Month USD LIBOR + 
 
  
134 bps), 3/4/21 
3,367,394 
9,451,000  
Wells Fargo & Co., 2.5%, 3/4/21 
9,538,269 
3,776,000  
Wells Fargo & Co., 3.0%, 1/22/21 
3,807,975 
6,430,000  
Wells Fargo & Co., 4.6%, 4/1/21 
6,566,556 
6,430,000(a)  
Wells Fargo Bank NA, 0.871% (3 Month USD LIBOR + 
 
  
62 bps), 5/27/22 
6,448,872 
  Total Banks $ 668,565,222 
  Beverages — 0.1% 
 
2,753,000  
Constellation Brands, Inc., 3.75%, 5/1/21 
$ 2,802,115 
1,907,000  
Pernod Ricard SA, 5.75%, 4/7/21 (144A) 
1,958,696 
  Total Beverages $ 4,760,811 
  Chemicals — 0.5% 
 
8,788,000(a)  
Albemarle Corp., 1.33% (3 Month USD LIBOR + 
 
  
105 bps), 11/15/22 
$ 8,756,265 
 
The accompanying notes are an integral part of these financial statements.
64 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Chemicals — (continued) 
 
15,830,000(a)  
DuPont de Nemours, Inc., 0.99% (3 Month USD 
 
 
 
LIBOR + 71 bps), 11/15/20 
$ 15,840,883 
 
 Total Chemicals $ 24,597,148 
 
 Diversified Financial Services — 0.9% 
 
12,490,000(a)  
American Express Co., 0.861% (3 Month USD LIBOR + 
 
 
 
61 bps), 8/1/22 
$ 12,568,598 
15,850,000(a)  
Capital One Financial Corp., 0.988% (3 Month USD 
 
 
 
LIBOR + 72 bps), 1/30/23 
15,857,598 
13,108,000(a)  
Charles Schwab Corp., 0.567% (3 Month USD LIBOR + 
 
 
 
32 bps), 5/21/21 
13,127,253 
 
 Total Diversified Financial Services $ 41,553,449 
 
 Electric — 0.6% 
 
9,175,000(a)  
Dominion Energy, Inc., 0.774% (3 Month USD LIBOR + 
 
 
 
53 bps), 9/15/23 
$ 9,189,689 
2,000,000(c)  
Dominion Energy, Inc., 2.715%, 8/15/21 
2,036,625 
2,803,000(a)  
Duke Energy Corp., 0.765% (3 Month USD LIBOR + 
 
 
 
50 bps), 5/14/21 (144A) 
2,809,666 
12,000,000(a)  
Florida Power & Light Co., 0.641% (3 Month USD 
 
 
 
LIBOR + 38 bps), 7/28/23 
12,008,748 
 
 Total Electric $ 26,044,728 
 
 Electronics — 0.1% 
 
6,425,000(a)  
Honeywell International, Inc., 0.498% (3 Month USD 
 
 
 
LIBOR + 23 bps), 8/19/22 
$ 6,430,124 
 
 Total Electronics $ 6,430,124 
 
 Gas — 0.3% 
 
6,225,000(a)  
Dominion Energy Gas Holdings LLC, 0.85% (3 Month 
 
 
 
USD LIBOR + 60 bps), 6/15/21 
$ 6,245,455 
9,080,000  
Dominion Energy Gas Holdings LLC, 2.8%, 11/15/20 
9,089,948 
 
 Total Gas $ 15,335,403 
 
 Healthcare-Services — 0.4% 
 
5,945,000(a)  
UnitedHealth Group, Inc., 0.345% (3 Month USD 
 
 
 
LIBOR + 7 bps), 10/15/20 
$ 5,945,213 
13,650,000  
UnitedHealth Group, Inc., 1.95%, 10/15/20 
13,658,576 
 
 Total Healthcare-Services $ 19,603,789 
 
 Insurance — 0.9% 
 
2,705,000(a)  
Allstate Corp., 0.648% (3 Month USD LIBOR + 
 
 
 
43 bps), 3/29/21 
$ 2,710,090 
3,129,000(a)  
Allstate Corp., 0.848% (3 Month USD LIBOR + 
 
 
 
63 bps), 3/29/23 
3,153,429 
2(a)  
Ambac LSNI LLC, 6.0% (3 Month USD LIBOR + 
 
 
 
500 bps), 2/12/23 (144A) 
10,500,000  
American International Group, Inc., 6.4%, 12/15/20 
10,627,267 
3,000,000  
Liberty Mutual Group, Inc., 5.0%, 6/1/21 (144A) 
3,091,413 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 65
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Insurance — (continued) 
 
4,380,000(a)  Metropolitan Life Global Funding I, 0.66% (SOFRRATE + 
 
  57 bps), 1/13/23 (144A) $ 4,395,111 
6,190,000  
Metropolitan Life Global Funding I, 2.4%, 1/8/21 (144A) 
6,225,481 
4,531,000(a)  New York Life Global Funding, 0.569% (3 Month USD 
 
  LIBOR + 32 bps), 8/6/21 (144A) 4,542,431 
5,733,000  New York Life Global Funding, 2.95%, 1/28/21 (144A) 5,782,707 
  Total Insurance $ 40,527,932 

 Machinery – Construction & Mining — 0.5% 
2,600,000(a)  Caterpillar Financial Services Corp., 0.528% (3 Month 
 
  USD LIBOR + 28 bps), 9/7/21 $ 2,604,964 
9,120,000(a)  Caterpillar Financial Services Corp., 0.67% (3 Month 
 
  USD LIBOR + 39 bps), 5/17/21 9,137,143 
9,091,000(a)  Caterpillar Financial Services Corp., 0.989% (3 Month 
 
  USD LIBOR + 74 bps), 5/13/22 9,183,018 
  Total Machinery – Construction & Mining $ 20,925,125 
  Machinery-Diversified — 0.3% 
 
5,997,000(a)  John Deere Capital Corp., 0.51% (3 Month USD 
 
  LIBOR + 26 bps), 9/10/21 $ 6,006,519 
5,512,000(a)  John Deere Capital Corp., 0.628% (3 Month USD 
 
  LIBOR + 38 bps), 3/7/22 5,526,988 
4,500,000(a)  John Deere Capital Corp., 0.648% (3 Month USD 
 
  LIBOR + 40 bps), 6/7/21 4,509,202 
  Total Machinery-Diversified $ 16,042,709 
  Media — 0.8% 
 
5,092,000(a)  Comcast Corp., 0.665% (3 Month USD LIBOR + 
 
  44 bps), 10/1/21 $ 5,110,469 
7,774,000(a)  NBCUniversal Enterprise, Inc., 0.625% (3 Month 
 
  USD LIBOR + 40 bps), 4/1/21 (144A) 7,787,453 
10,940,000(a)  Walt Disney Co., 0.496% (3 Month USD LIBOR + 
 
  25 bps), 9/1/21 10,956,300 
9,910,000(a)  Walt Disney Co., 0.636% (3 Month USD LIBOR + 
 
  39 bps), 9/1/22 9,946,809 
3,909,000  Walt Disney Co., 4.5%, 2/15/21 3,970,237 
  Total Media $ 37,771,268 
  Oil & Gas — 1.4% 
 
2,775,000(a)  BP Capital Markets Plc, 0.877% (3 Month USD LIBOR + 
 
  65 bps), 9/19/22 $ 2,782,718 
5,766,000(a)  BP Capital Markets Plc, 1.107% (3 Month USD LIBOR + 
 
  87 bps), 9/16/21 5,800,827 
7,045,000  Canadian Natural Resources, Ltd., 3.45%, 11/15/21 7,205,258 
2,295,000(a)  Chevron Corp., 0.781% (3 Month USD LIBOR + 
 
  53 bps), 3/3/22 2,308,432 
14,000,000(a)  Chevron Corp., 1.153% (3 Month USD LIBOR + 
 
  90 bps), 5/11/23 14,259,248 
 
The accompanying notes are an integral part of these financial statements.
66 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Oil & Gas — (continued) 
 
14,505,000(a)  
Exxon Mobil Corp., 0.61% (3 Month USD LIBOR + 
 
 
 
33 bps), 8/16/22 
$ 14,572,912 
8,710,000(a)  
Phillips 66, 0.834% (3 Month USD LIBOR + 
 
 
 
60 bps), 2/26/21 
8,710,935 
7,200,000(a)  
Valero Energy Corp., 1.403% (3 Month USD LIBOR + 
 
 
 
115 bps), 9/15/23 
7,175,304 
 
 Total Oil & Gas $ 62,815,634 
 
 Pharmaceuticals — 1.8% 
 
12,080,000(a)  
AbbVie, Inc., 0.597% (3 Month USD LIBOR + 
 
 
 
35 bps), 5/21/21 (144A) 
$ 12,091,971 
23,942,000(a)  
AbbVie, Inc., 0.897% (3 Month USD LIBOR + 
 
 
 
65 bps), 11/21/22 (144A) 
24,051,846 
4,670,000(a)  
Bayer US Finance II LLC, 0.855% (3 Month USD LIBOR + 
 
 
 
63 bps), 6/25/21 (144A) 
4,679,296 
12,890,000(a)  
Becton Dickinson & Co., 1.28% (3 Month USD LIBOR + 
 
 
 
103 bps), 6/6/22 
12,979,207 
4,676,000(a)  
Cardinal Health, Inc., 1.02% (3 Month USD LIBOR + 
 
 
 
77 bps), 6/15/22 
4,704,288 
6,730,000(a)  
Cigna Corp., 0.896% (3 Month USD LIBOR + 
 
 
 
65 bps), 9/17/21 
6,731,324 
15,600,000(a)  
Zoetis, Inc., 0.693% (3 Month USD LIBOR + 
 
 
 
44 bps), 8/20/21 
15,629,628 
 
 Total Pharmaceuticals $ 80,867,560 
 
 Pipelines — 0.7% 
 
9,000,000  
Enterprise Products Operating LLC, 2.8%, 2/15/21 
$ 9,081,003 
3,750,000  
Enterprise Products Operating LLC, 2.85%, 4/15/21 
3,791,785 
3,453,000  
Kinder Morgan, Inc., 5.0%, 2/15/21 (144A) 
3,496,340 
15,605,000(a)  
MPLX LP, 1.342% (3 Month USD LIBOR + 
 
 
 
110 bps), 9/9/22 
15,605,630 
1,380,000  
Sunoco Logistics Partners Operations LP, 4.4%, 4/1/21 
1,400,252 
 
 Total Pipelines $ 33,375,010 
 
 REITs — 0.2% 
 
7,910,000  
Essex Portfolio LP, 5.2%, 3/15/21 
$ 7,979,208 
 
 Total REITs $ 7,979,208 
 
 Semiconductors — 0.6% 
 
23,276,000  
Broadcom Corp./Broadcom Cayman Finance, Ltd., 
 
 
 
2.2%, 1/15/21 
$ 23,365,305 
4,000,000(a)  
Intel Corp., 0.603% (3 Month USD LIBOR + 
 
 
 
35 bps), 5/11/22 
4,018,467 
 
 Total Semiconductors $ 27,383,772 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 67
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Telecommunications — 0.4% 
 
17,944,000(a)  AT&T, Inc., 1.225% (3 Month USD LIBOR + 
 
  95 bps), 7/15/21 $ 18,064,054 
  Total Telecommunications $ 18,064,054 
  Transportation — 0.2% 
 
10,000,000(a)  United Parcel Service, Inc., 0.66% (3 Month USD 
 
  LIBOR + 38 bps), 5/16/22 $ 10,032,210 
  Total Transportation $ 10,032,210 
  Trucking & Leasing — 0.3% 
 
1,400,000(a)  Aviation Capital Group LLC, 0.938% (3 Month USD 
 
  LIBOR + 67 bps), 7/30/21 (144A) $ 1,362,826 
5,010,000(a)  GATX Corp., 0.969% (3 Month USD LIBOR + 
 
  72 bps), 11/5/21 5,003,505 
1,000,000  Penske Truck Leasing Co. LP/PTL Finance Corp., 
 
  3.3%, 4/1/21 (144A) 1,011,748 
6,350,000  Penske Truck Leasing Co. LP/PTL Finance Corp., 
 
  3.375%, 2/1/22 6,556,852 
2,870,000  Penske Truck Leasing Co. LP/PTL Finance Corp., 
 
  3.65%, 7/29/21 (144A) 2,937,053 
  Total Trucking & Leasing $ 16,871,984 
  TOTAL CORPORATE BONDS 
 
  
(Cost $1,281,256,151) 
$1,288,253,059 

 FOREIGN GOVERNMENT BOND — 0.5% 
  of Net Assets 
 
  United States — 0.5% 
 
25,000,000(a)  Federal National Mortgage Association, 0.29% 
 
  (SOFRRATE + 22 bps), 3/16/22 $ 25,055,751 
  Total United States $ 25,055,751 
  TOTAL FOREIGN GOVERNMENT BOND 
 
  
(Cost $24,977,539) 
$ 25,055,751 

 INSURANCE-LINKED SECURITIES — 2.3% 
  of Net Assets# 
 
  Event Linked Bonds — 1.5% 
 
  Earthquakes – California — 0.1% 
 
600,000(a)  Ursa Re, 4.237% (3 Month U.S. Treasury Bill + 
 
  414 bps), 12/10/20 (144A) $ 599,400 
1,000,000(a)  Ursa Re, 5.327% (3 Month U.S. Treasury Bill + 
 
  523 bps), 9/24/21 (144A) 998,700 
750,000(a)  Ursa Re, 5.847% (3 Month U.S. Treasury Bill + 
 
  575 bps), 12/10/22 (144A) 749,550 
  
 
$ 2,347,650 
  Earthquakes – Chile — 0.1% 
 
1,800,000(a)  International Bank for Reconstruction & Development, 
 
  
2.58% (3 Month USD LIBOR + 250 bps), 2/15/21 (144A) 
$ 1,792,800 
 
The accompanying notes are an integral part of these financial statements.
68 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Earthquakes – Colombia — 0.0%† 
 
1,300,000(a)  
International Bank for Reconstruction & Development, 
 
 
 
3.08% (3 Month USD LIBOR + 300 bps), 
 
 
 
2/15/21 (144A) 
$ 1,294,540 
 
 Earthquakes – Japan — 0.0%† 
 
750,000(a)  
Kizuna Re II, 1.972% (3 Month U.S. Treasury Bill + 
 
 
 
188 bps), 4/11/23 (144A) 
$ 747,900 
250,000(a)  
Kizuna Re II, 2.597% (3 Month U.S. Treasury Bill + 
 
 
 
250 bps), 4/11/23 (144A) 
249,250 
700,000(a)  
Nakama Re, 2.2% (6 Month USD LIBOR + 220 bps), 
 
 
 
10/13/21 (144A) 
697,970 
 
 
 
$ 1,695,120 
 
 Earthquakes – Mexico — 0.0%† 
 
500,000(a)  
International Bank for Reconstruction & Development, 
 
 
 
3.669% (3 Month USD LIBOR + 350 bps), 
 
 
 
3/13/24 (144A) 
$ 499,450 
 
 Earthquakes – Peru — 0.0%† 
 
700,000(a)  
International Bank for Reconstruction & Development, 
 
 
 
6.08% (3 Month USD LIBOR + 600 bps), 
 
 
 
2/15/21 (144A) 
$ 702,380 
 
 Health – U.S. — 0.1% 
 
250,000(a)  
Vitality Re VIII, 1.847% (3 Month U.S. Treasury Bill + 
 
 
 
175 bps), 1/8/21 (144A) 
$ 248,500 
1,000,000(a)  
Vitality Re VIII, 2.097% (3 Month U.S. Treasury Bill + 
 
 
 
200 bps), 1/8/21 (144A) 
991,500 
3,500,000(a)  
Vitality Re X, 1.847% (3 Month U.S. Treasury Bill + 
 
 
 
175 bps), 1/10/23 (144A) 
3,480,750 
1,750,000(a)  
Vitality Re X, 2.097% (3 Month U.S. Treasury Bill + 
 
 
 
200 bps), 1/10/23 (144A) 
1,736,875 
 
 
 
$ 6,457,625 
 
 Inland Flood – U.S. — 0.0%† 
 
500,000(a)  
FloodSmart Re, 11.927% (1 Month U.S. Treasury Bill + 
 
 
 
1,183 bps), 3/7/22 (144A) 
$ 496,500 
 
 Multiperil – Florida — 0.0%† 
 
250,000(a)  
Sanders RE II, 5.5% (3 Month U.S. Treasury Bill + 
 
 
 
550 bps), 6/7/23 (144A) 
$ 254,900 
 
 Multiperil – Japan — 0.0%† 
 
250,000(a)  
Akibare Re, 2.115% (3 Month USD LIBOR + 
 
 
 
190 bps), 4/7/22 (144A) 
$ 247,275 
500,000(a)  
Akibare Re, 2.125% (3 Month USD LIBOR + 
 
 
 
190 bps), 4/7/22 (144A) 
496,400 
 
 
 
$ 743,675 
 
 Multiperil – U.S. — 0.5% 
 
1,500,000(a)  
Bonanza RE, 4.844% (3 Month U.S. Treasury Bill + 
 
 
 
475 bps), 2/20/24 (144A) 
$ 1,500,750 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 69
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Multiperil – U.S. — (continued) 
 
250,000(a)  
Bowline Re, Series Series 2018-1, 4.854% (3 Month U.S. 
 
 
 
Treasury Bill + 476 bps), 5/23/22 (144A) 
$ 249,575 
625,000(a)  
Caelus Re V, 0.597% (1 Month U.S. Treasury Bill + 
 
 
 
50 bps), 6/5/24 (144A) 
568,750 
500,000(a)  
Caelus Re V, 3.287% (3 Month U.S. Treasury Bill + 
 
 
 
319 bps), 6/7/21 (144A) 
499,000 
750,000(a)  
Caelus Re V, 4.127% (3 Month U.S. Treasury Bill + 
 
 
 
403 bps), 6/7/21 (144A) 
741,675 
750,000(a)  
Caelus Re VI, 5.597% (3 Month U.S. Treasury Bill + 
 
 
 
550 bps), 6/7/24 (144A) 
749,250 
500,000(a)  
Fortius Re II, 3.42% (6 Month USD LIBOR + 
 
 
 
342 bps), 7/7/21 (144A) 
500,950 
250,000(a)  
Kilimanjaro Re, 5.044% (3 Month USD LIBOR + 
 
 
 
494 bps), 5/6/22 (144A) 
251,375 
350,000(a)  
Kilimanjaro II Re, 6.3% (6 Month USD LIBOR + 
 
 
 
630 bps), 4/20/21 (144A) 
350,350 
1,700,000(a)  
Kilimanjaro II Re, 7.91% (6 Month USD LIBOR + 
 
 
 
791 bps), 4/21/22 (144A) 
1,698,300 
2,350,000(a)  
Residential Reinsurance 2016, 4.177% (3 Month U.S. 
 
 
 
Treasury Bill + 408 bps), 12/6/20 (144A) 
2,350,470 
1,250,000(a)  
Residential Reinsurance 2016, 5.697% (3 Month U.S. 
 
 
 
Treasury Bill + 560 bps), 12/6/20 (144A) 
1,252,375 
2,100,000(a)  
Residential Reinsurance 2017, 3.367% (3 Month U.S. 
 
 
 
Treasury Bill + 327 bps), 6/6/21 (144A) 
2,104,410 
2,900,000(a)  
Residential Reinsurance 2017, 6.027% (3 Month U.S. 
 
 
 
Treasury Bill + 593 bps), 12/6/21 (144A) 
2,869,550 
1,250,000(a)  
Residential Reinsurance 2018, 3.457% (3 Month U.S. 
 
 
 
Treasury Bill + 336 bps), 6/6/22 (144A) 
1,237,625 
500,000(a)  
Residential Reinsurance 2019, 4.747% (3 Month U.S. 
 
 
 
Treasury Bill + 465 bps), 6/6/23 (144A) 
494,250 
500,000(a)  
Residential Reinsurance 2020, 5.597% (3 Month U.S. 
 
 
 
Treasury Bill + 550 bps), 6/6/24 (144A) 
503,900 
250,000(a)  
Sanders Re, 2.975% (6 Month USD LIBOR + 293 bps), 
 
 
 
12/6/21 (144A) 
246,600 
1,000,000(a)  
Spectrum Capital, Ltd., 5.965% (6 Month USD LIBOR + 
 
 
 
575 bps), 6/8/21 (144A) 
1,002,400 
3,350,000(a)  
Tailwind Re, 7.457% (3 Month U.S. Treasury Bill + 
 
 
 
736 bps), 1/8/22 (144A) 
3,396,900 
 
 
 
$ 22,568,455 
 
 Multiperil – U.S. & Canada — 0.1% 
 
2,500,000(a)  
Hypatia Ltd., 6.847% (3 Month U.S. Treasury Bill + 
 
 
 
675 bps), 6/7/23 (144A) 
$ 2,610,750 
1,000,000(a)  
Hypatia Ltd., 9.847% (3 Month U.S. Treasury Bill + 
 
 
 
975 bps), 6/7/23 (144A) 
1,046,500 
 
 
 
$ 3,657,250 
 
The accompanying notes are an integral part of these financial statements.
70 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Multiperil – U.S. Regional — 0.0%† 
 
700,000(a)  
First Coast Re II Pte, 5.66% (3 Month U.S. Treasury Bill + 
 
  
566 bps), 6/7/23 (144A) 
$ 701,330 
1,250,000(a)  
Long Point Re III, 2.847% (3 Month U.S. Treasury Bill + 
 
  
275 bps), 6/1/22 (144A) 
1,250,125 
400,000(a)  
Matterhorn Re, 5.094% (3 Month U.S. Treasury Bill + 
 
  
500 bps), 1/8/24 (144A) 
401,080 
  
 
$ 2,352,535 
  Multiperil – Worldwide — 0.1% 
 
1,250,000(a)  
Galilei Re, 5.174% (6 Month USD LIBOR + 513 bps), 
 
  
1/8/21 (144A) 
$ 1,250,000 
1,150,000(a)  
Galilei Re, 5.724% (6 Month USD LIBOR + 568 bps), 
 
  
1/8/21 (144A) 
1,150,000 
2,300,000(a)  
Galilei Re, 5.924% (6 Month USD LIBOR + 588 bps), 
 
  
1/8/21 (144A) 
2,301,150 
500,000(a)  
Kendall Re, 5.339% (3 Month USD LIBOR + 525 bps), 
 
  
5/6/21 (144A) 
500,500 
  
 
$ 5,201,650 
  Pandemic – U.S. — 0.1% 
 
3,000,000(a)  
Vitality Re X, 1.597% (3 Month U.S. Treasury Bill + 
 
  
150 bps), 1/9/24 (144A) 
$ 2,980,500 
1,250,000(a)  
Vitality Re XI, 1.897% (3 Month U.S. Treasury Bill + 
 
  
180 bps), 1/9/24 (144A) 
1,240,000 
  
 
$ 4,220,500 
  Pandemic – Worldwide — 0.0%† 
 
1,750,000(a)  
Vita Capital VI, Ltd., 3.084% (6 Month USD LIBOR + 
 
  
290 bps), 1/8/21 (144A) 
$ 1,487,500 
  Windstorm – Florida — 0.1% 
 
2,500,000(a)  
Integrity Re, 4.05% (3 Month USD LIBOR + 
 
  
405 bps), 6/10/22 (144A) 
$ 2,453,000 
  Windstorm – Japan — 0.0%† 
 
1,500,000(a)  
Aozora Re, 3.509% (6 Month USD LIBOR + 200 bps), 
 
  
4/7/21 (144A) 
$ 1,500,000 
  Windstorm – Mexico — 0.0%† 
 
500,000  
International Bank for Reconstruction & Development, 
 
  
6.733%, 3/13/24 
$ 499,450 
  Windstorm – Texas — 0.1% 
 
2,500,000(a)  
Alamo Re II, 5.844% (1 Month U.S. Treasury Bill + 
 
  
575 bps), 6/8/23 (144A) 
$ 2,582,500 
  Windstorm – U.S. — 0.0%† 
 
250,000(a)  
Bowline Re, 8.944% (3 Month U.S. Treasury Bill + 
 
  
885 bps), 3/20/23 (144A) 
$ 253,625 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 71
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Windstorm – U.S. Regional — 0.2% 
 
2,500,000(d)  
Matterhorn Re, 12/7/21 (144A) 
$ 2,263,000 
1,500,000(a)  
Matterhorn Re, 6.344% (3 Month U.S. Treasury Bill + 
 
  
625 bps), 12/7/21 (144A) 
1,503,450 
250,000(a)  
Matterhorn Re, 7.094% (3 Month U.S. Treasury Bill + 
 
  
700 bps), 12/7/21 (144A) 
254,875 
2,250,000(a)  
Matterhorn Re, 10.094% (3 Month U.S. Treasury Bill + 
 
  
1,000 bps), 12/7/21 (144A) 
2,281,500 
250,000(d)  
Matterhorn Re, 12/7/20 (144A) 
243,125 
500,000(d)  
Matterhorn Re 2019-1, 12/7/20 (144A) 
495,700 
2,000,000(a)  
Matterhorn Re 2020-1, 7.594% (3 Month U.S. Treasury 
 
  
Bill + 750 bps), 12/7/21 (144A) 
2,004,600 
  
 
$ 9,046,250 
  Total Event Linked Bonds $ 72,107,355 
Face  
 
 
Amount  
 
 
USD ($)  
 
 
  Collateralized Reinsurance — 0.4% 
 
  Earthquakes – California — 0.0%† 
 
2,500,000+(e)(f)  
Adare Re 2020, 1/31/21 
$ 2,606,675 
  Multiperil – Massachusetts — 0.1% 
 
3,000,000+(e)(f)  
Denning Re 2019, 7/31/21 
$ 3,081,638 
  Multiperil – U.S. — 0.1% 
 
500,000+(e)(f)  
Dingle Re 2019, 2/1/21 
$ 510,263 
250,000+(e)(f)  
Dingle Re 2020, 1/31/21 
253,771 
4,000,000+(e)(f)  
Port Royal Re 2019, 5/31/21 
4,045,158 
  
 
$ 4,809,192 
  Multiperil – U.S. & Canada — 0.1% 
 
3,250,000+(e)(f)  
Leven Re 2020, 1/31/21 
$ 3,273,283 
  Multiperil – U.S. Regional — 0.1% 
 
2,750,000+(e)(f)  
Ailsa Re 2019, 6/30/21 
$ 2,818,475 
  Multiperil – Worldwide — 0.0%† 
 
1,000,000+(e)(f)  
Cypress Re 2017, 1/10/21 
$ 18,200 
24,000+(e)  
Limestone Re 2016-1, 8/31/21 
70 
40,000+(e)  
Limestone Re 2016-1, 8/31/21 
116 
223,000+(e)(f)  
Limestone Re 2019-2, 3/1/23 (144A) 
388,912 
2,500,000+(e)(f)  
Resilience Re, 5/1/21 
250 
2,000,000+(e)(f)  
Resilience Re, 4/6/21 (144A) 
200 
  
 
$ 407,748 
 
The accompanying notes are an integral part of these financial statements.
72 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Face  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Windstorm – Florida — 0.0%† 
 
2,000,000+(e)(f)  
Formby Re 2018, 2/28/21 
$ 353,832 
800,000+(e)(f)  
Portrush Re 2017, 6/15/21 
510,480 
  
 
$ 864,312 
  Windstorm – U.S. Regional — 0.0%† 
 
500,000+(e)(f)  
Oakmont Re 2017, 4/30/21 
$ 14,700 
2,500,000+(e)(f)  
Oakmont Re 2019, 4/30/21 
1,730,780 
  
 
$ 1,745,480 
  Total Collateralized Reinsurance $ 19,606,803 
  Industry Loss Warranties — 0.1% 
 
  Multiperil – U.S. — 0.1% 
 
2,250,000+(e)(f)  
Scotscraig Re 2020, 1/31/21 
$ 2,239,890 
  Total Industry Loss Warranties $ 2,239,890 
  Reinsurance Sidecars — 0.3% 
 
  Multiperil – U.S. — 0.0%† 
 
2,000,000+(e)(f)  
Carnoustie Re 2017, 11/30/21 
$ 263,600 
1,100,000+(e)  
Carnoustie Re 2019, 12/31/22 
2,090 
1,500,000+(e)(f)  
Castle Stuart Re 2018, 12/1/21 
261,880 
2,000,000+(f)(g)  
Harambee Re 2018, 12/31/21 
22,400 
4,000,000+(g)  
Harambee Re 2019, 12/31/22 
46,000 
  
 
$ 595,970 
  Multiperil – Worldwide — 0.3% 
 
2,000+(e)  
Alturas Re 2019-1, 3/10/23 (144A) 
$ 9,819 
36,448+(e)  
Alturas Re 2019-2, 3/10/22 
194,498 
2,500,000+(e)(f)  
Artex Sac, Ltd. Bantry Re, 2016, 3/31/21 
201,500 
2,000,000+(e)(f)  
Bantry Re 2017, 3/31/21 
472,200 
2,000,000+(e)(f)  
Bantry Re 2018, 12/31/21 
22,800 
4,000,000+(e)  
Bantry Re 2019, 12/31/22 
135,855 
1,250,000+(e)(f)  
Berwick Re 2017-1, 2/1/21 
41,375 
5,120,164+(e)(f)  
Berwick Re 2018-1, 12/31/21 
623,124 
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 
65,550 
113,405+(e)  
Eden Re II, 3/22/22 (144A) 
70,950 
4,000+(e)(f)  
Eden Re II, 3/22/23 (144A) 
32,466 
35,797+(e)(f)  
Eden Re II, 3/22/23 (144A) 
298,987 
75,000+(e)  
Eden Re II, 3/22/22 (144A) 
48,741 
1,300,000+(e)(f)  
Gleneagles Re 2016, 11/30/20 
40,560 
2,118,314+(e)(f)  
Gullane Re 2018, 12/31/21 
2,168,623 
2,000+(e)  
Limestone Re 2018, 3/1/22 
68,353 
500,000+(g)  
Lion Rock Re 2019, 1/31/21 
39,100 
4,000,000+(f)(g)  
Lorenz Re 2018, 7/1/21 
109,600 
2,744,544+(f)(g)  
Lorenz Re 2019, 6/30/22 
265,397 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 73
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Face  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Multiperil – Worldwide — (continued) 
 
3,000,000+(e)(f)  Merion Re 2018-2, 12/31/21 $ 3,232,500 
977,820+(g)  NCM Re 2019, 12/31/22 113,623 
1,500,000+(e)  Pangaea Re 2016-2, 11/30/20 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, 7/1/23 105,799 
2,400,000+(e)(f)  Sector Re V, 12/1/23 (144A) 801,252 
1,600,000+(e)(f)  Sector Re V, 12/1/24 (144A) 1,682,001 
800,000+(e)(f)  Sector Re V, Series 9, Class A, 3/1/24 (144A) 337,059 
1,861+(e)  Sector Re V, Series 9, Class G, 3/1/24 (144A) 49,159 
1,250,000+(e)(f)  St. Andrews Re 2017-1, 2/1/21 84,750 
1,737,984+(e)(f)  St. Andrews Re 2017-4, 6/1/21 171,018 
750,000+(f)(g)  Thopas Re 2018, 12/31/21 — 
3,000,000+(f)(g)  Thopas Re 2019, 12/31/22 447,600 
2,600,000+(e)(f)  Versutus Re 2017, 11/30/21 — 
2,000,000+(e)(f)  Versutus Re 2018, 12/31/21 38,000 
1,765,095+(e)  Versutus Re 2019-A, 12/31/21 78,900 
1,434,906+(e)  Versutus Re 2019-B, 12/31/21 64,140 
750,000+(f)(g)  Viribus Re 2018, 12/31/21 27,300 
2,500,000+(g)  Viribus Re 2019, 12/31/22 100,250 
1,724,784+(e)(f)  Woburn Re 2018, 12/31/21 158,914 
809,418+(e)(f)  Woburn Re 2019, 12/31/22 275,802 
  
 
$ 13,300,803 
  Total Reinsurance Sidecars $ 13,896,773 
  TOTAL INSURANCE-LINKED SECURITIES 
 
  
(Cost $109,772,139) 
$ 107,850,821 
Principal  
 
 
Amount  
 
 
USD ($)  
 
 
  MUNICIPAL BOND — 0.0%† of Net 
 
  Assets(h) 
 
  Municipal Student Loan — 0.0%† 
 
68,864(a)  Louisiana Public Facilities Authority, Student Loan 
 
  Backed, Series A, 1.168% (3 Month USD LIBOR + 
 
  90 bps), 4/26/27 $ 68,919 
  Total Municipal Student Loan $ 68,919 
  TOTAL MUNICIPAL BOND 
 
  
(Cost $69,141) 
$ 68,919 
 
The accompanying notes are an integral part of these financial statements.
74 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  SENIOR SECURED FLOATING RATE LOAN 
 

 INTERESTS — 3.8% of Net Assets*(a) 
  Aerospace & Defense — 0.0%† 
 
2,400,024  American Airlines, Inc., 2018 Replacement Term 
 
  Loan, 1.895% (LIBOR + 175 bps), 6/27/25 $ 1,492,681 
1,000,000(i)  MAG DS Corp., Initial Term Loan, 4/1/27 955,625 
740,625  MRO Holdings, Inc., Initial Term Loan, 5.22% (LIBOR + 
 
  500 bps), 6/4/26 592,500 
85,691  United Airlines, Inc., Refinanced Term Loan, 1.895% 
 
  (LIBOR + 175 bps), 4/1/24 80,335 
  Total Aerospace & Defense $ 3,121,141 
  Automobile — 0.2% 
 
2,000,000  American Axle & Manufacturing, Inc., Tranche B 
 
  Term Loan, 3.0% (LIBOR + 225 bps), 4/6/24 $ 1,925,714 
156,395  CWGS Group LLC (aka Camping World, Inc.), Term 
 
  Loan, 3.5% (LIBOR + 275 bps), 11/8/23 152,681 
2,000,000(i)  Dana, Inc., 2018 New Term Loan B Advance (LIBOR + 
 
  225 bps), 2/27/26 1,952,500 
2,000,000  Navistar, Inc., Tranche B Term Loan, 3.66% (LIBOR + 
 
  350 bps), 11/6/24 1,989,062 
291,667  Visteon Corp., New Term Loan, 1.912% (LIBOR + 
 
  175 bps), 3/25/24 284,314 
287,222(i)  Wabash National Corp., Term Loan B, 9/17/27 286,145 
  Total Automobile $ 6,590,416 
  Beverage, Food & Tobacco — 0.0%† 
 
990,000  US Foods, Inc. (aka U.S. Foodservice, Inc.), Incremental 
 
  B-2019 Term Loan, 2.147% (LIBOR + 
 
  200 bps), 9/13/26 $ 951,173 
  Total Beverage, Food & Tobacco $ 951,173 
  Broadcasting & Entertainment — 0.1% 
 
1,087,297  Gray Television, Inc., Term B-2 Loan, 2.405% (LIBOR + 
 
  225 bps), 2/7/24 $ 1,065,551 
4,000,001  Gray Television, Inc., Term C Loan, 2.655% (LIBOR + 
 
  250 bps), 1/2/26 3,936,389 
  Total Broadcasting & Entertainment $ 5,001,940 
  Building Materials — 0.1% 
 
1,091,190  Circor International, Inc., New Term Loan, 4.25% 
 
  (LIBOR + 325 bps), 12/11/24 $ 1,070,730 
2,725,947  Summit Materials LLC, New Term Loan, 2.145% 
 
  (LIBOR + 200 bps), 11/21/24 2,705,077 
  Total Building Materials $ 3,775,807 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 75
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Buildings & Real Estate — 0.1% 
 
2,417,462  
Beacon Roofing Supply, Inc., Initial Term Loan, 2.397% 
 
  
(LIBOR + 225 bps), 1/2/25 
$ 2,346,449 
2,100,000  
VICI Properties 1 LLC, Term B Loan, 1.906% (LIBOR + 
 
  
175 bps), 12/20/24 
2,034,900 
635,618  
WireCo WorldGroup, Inc. (WireCo WorldGroup 
 
  
Finance LP), First Lien Initial Term Loan, 6.0% (LIBOR + 
 
  
500 bps), 9/29/23 
556,232 
  Total Buildings & Real Estate $ 4,937,581 
  Chemicals — 0.1% 
 
2,000,000(i)  
Element Solutions, Inc. (Macdermid, Inc.), Tranche B-1 
 
  
Term Loan, 1/31/26 
$ 1,960,000 
  Total Chemicals $ 1,960,000 
  Chemicals, Plastics & Rubber — 0.4% 
 
2,396,940  
Axalta Coating Systems Dutch Holding B BV (Axalta 
 
  
Coating Systems U.S. Holdings, Inc.), Term B-3 Dollar 
 
  
Loan, 1.97% (LIBOR + 175 bps), 6/1/24 
$ 2,344,807 
1,994,426  
Berry Global, Inc. (fka Berry Plastics Corp.), Term X 
 
  
Loan, 2.156% (LIBOR + 200 bps), 1/19/24 
1,973,028 
4,443,750  
Berry Global, Inc. (fka Berry Plastics Corp.), Term Y 
 
  
Loan, 2.156% (LIBOR + 200 bps), 7/1/26 
4,317,534 
1,897,792  
PQ Corp., Third Amendment Tranche B-1 Term Loan, 
 
  
2.511% (LIBOR + 225 bps), 2/7/27 
1,861,734 
751,117  
Reynolds Group Holdings, Inc., Tranche B-1 US Term 
 

 
Loan, 3.979% (LIBOR + 275 bps/PRIME + 175 +
 
  
0 bps), 2/5/23 
745,014 
4,471,317  
Tronox Finance LLC, First Lien Initial Dollar Term Loan, 
 
  
3.177% (LIBOR + 300 bps), 9/23/24 
4,415,425 
97,007  
Twist Beauty International Holdings SA, Facility B2, 
 
  
4.0% (LIBOR + 300 bps), 4/22/24 
93,551 
  Total Chemicals, Plastics & Rubber $ 15,751,093 
  Computers & Electronics — 0.2% 
 
700,000  
Celestica, Inc., Incremental Term B-2 Loan, 2.645% 
 
  
(LIBOR + 250 bps), 6/27/25 
$ 693,000 
1,150,000  
LogMeIn, Inc., First Lien Initial Term Loan, 4.906% 
 
  
(LIBOR + 475 bps), 8/31/27 
1,113,583 
3,476,222  
NCR Corp., Initial Term Loan, 2.65% (LIBOR + 
 
  
250 bps), 8/28/26 
3,395,834 
1,974,684  
Pitney Bowes, Inc., Incremental Tranche B Term Loan, 
 
  
5.65% (LIBOR + 550 bps), 1/7/25 
1,925,316 
  Total Computers & Electronics $ 7,127,733 
  Consumer Services — 0.0%† 
 
1,030,968  
Prime Security Services Borrower LLC (aka Protection 1 
 

 
Security Solutions), First Lien 2019 Refinancing
 
  
Term B-1 Loan, 4.25% (LIBOR + 325 bps), 9/23/26 
$ 1,022,959 
  Total Consumer Services $ 1,022,959 
 
The accompanying notes are an integral part of these financial statements.
76 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Diversified & Conglomerate Manufacturing — 0.0%† 
 
904,422  
Delos Finance S.a.r.l., New Term Loan, 1.97% (LIBOR + 
 
 
 
175 bps), 10/6/23 
$ 886,334 
 
 Total Diversified & Conglomerate Manufacturing $ 886,334 

 Diversified & Conglomerate Service — 0.1% 
1,990,799  
Avis Budget Car Rental LLC, New Tranche B Term 
 
 
 
Loan, 2.4% (LIBOR + 225 bps), 8/6/27 
$ 1,771,811 
1,858,271  
Bright Horizons Family Solutions LLC (fka Bright 
 
 
 
Horizons Family Solutions, Inc.), Term B Loan, 2.5% 
 
 
 
(LIBOR + 175 bps), 11/7/23 
1,806,589 
1,024,387  
Change Healthcare Holdings LLC, Closing Date Term 
 
 
 
Loan, 3.5% (LIBOR + 250 bps), 3/1/24 
1,005,740 
487,704  
DG Investment Intermediate Holdings 2, Inc. (aka 
 
 
 
Convergint Technologies Holdings LLC), First Lien 
 
 
 
Initial Term Loan, 3.75% (LIBOR + 300 bps), 2/3/25 
468,195 
463,691  
DTI Holdco, Inc., Replacement B-1 Term Loan, 5.75% 
 
 
 
(LIBOR + 475 bps), 9/29/23 
407,063 
1,900,000  
DynCorp International, Inc., Term Loan, 7.0% (LIBOR + 
 
 
 
600 bps), 8/18/25 
1,890,500 
408,702  
Intrado Corp., Initial Term B Loan, 5.0% (LIBOR + 
 
 
 
400 bps), 10/10/24 
373,816 
1,940,000  
Iqvia, Inc. (Quintiles IMS), Incremental Term B-2 Dollar 
 
 
 
Loan, 1.897% (LIBOR + 175 bps), 1/17/25 
1,918,175 
1,475,298  
Outfront Media Capital LLC (Outfront Media Capital 
 

 
Corp.), Extended Term Loan, 1.901% (LIBOR +
 
 
 
175 bps), 11/18/26 
1,443,180 
597,730  
Tempo Acquisition LLC, Extended Term Loan, 3.75% 
 
 
 
(LIBOR + 325 bps), 11/2/26 
582,600 
 
 Total Diversified & Conglomerate Service $ 11,667,669 
 
 Electric & Electrical — 0.1% 
 
2,000,000  
Dell International LLC (EMC Corp.), Refinancing Term 
 
 
 
B-1 Loan, 2.75% (LIBOR + 200 bps), 9/19/25 
$ 1,993,942 
389,856  
Rackspace Technology Global, Inc., First Lien Term B 
 
 
 
Loan, 4.0% (LIBOR + 300 bps), 11/3/23 
383,642 
 
 Total Electric & Electrical $ 2,377,584 
 
 Electronics — 0.2% 
 
698,250  
BY Crown Parent LLC, Initial B-1 Term Loan, 4.0% 
 
 
 
(LIBOR + 300 bps), 2/2/26 
$ 692,140 
2,681,589  
Science Applications International Corp., Tranche B2 
 
 
 
Term Loan, 2.397% (LIBOR + 225 bps), 3/12/27 
2,651,979 
2,351,962  
Scientific Games International, Inc., Initial Term B-5 
 
 
 
Loan, 3.471% (LIBOR + 275 bps), 8/14/24 
2,224,662 
1,292,415  
Western Digital Corp., US Term B-4 Loan, 1.906% 
 
 
 
(LIBOR + 175 bps), 4/29/23 
1,285,146 
 
 Total Electronics $ 6,853,927 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 77
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Entertainment & Leisure — 0.0%† 
 
1,496,250  
Carnival Corp., Initial Advance Term Loan, 8.5% 
 
  
(LIBOR + 750 bps), 6/30/25 
$ 1,517,447 
  Total Entertainment & Leisure $ 1,517,447 
  Environmental Services — 0.1% 
 
2,085,246  
GFL Environmental, Inc., Effective Date Incremental 
 
  
Term Loan, 4.0% (LIBOR + 300 bps), 5/30/25 
$ 2,079,084 
  Total Environmental Services $ 2,079,084 
  Financial Services — 0.1% 
 
1,995,000  
Cardtronics USA, Inc., Initial Term Loan, 5.0% (LIBOR + 
 
  
400 bps), 6/29/27 
$ 1,998,116 
1,500,000(i)  
Citadel Securities LP, 2020 Repriced Term 
 
  
Loan, 2/27/26 
1,493,445 
500,000(i)  
EFS Cogen Holdings I LLC, Term Loan B, 9/24/27 
499,062 
997,487  
Hudson River Trading LLC, 2020 Repriced Term 
 
  
Loan, 3.145% (LIBOR + 300 bps), 2/18/27 
977,538 
  Total Financial Services $ 4,968,161 
  Healthcare — 0.0%† 
 
522,654  
Grifols Worldwide Operations, Ltd., Dollar Tranche B 
 
  
Term Loan, 2.1% (LIBOR + 200 bps), 11/15/27 
$ 513,018 
358,343  
Horizon Therapeutics USA, Inc., Seventh Amendment 
 
  
Refinancing Term Loan, 2.188% (LIBOR + 
 
  
200 bps), 5/22/26 
355,880 
  Total Healthcare $ 868,898 
  Healthcare & Pharmaceuticals — 0.1% 
 
1,259,734  
Acadia Healthcare Co., Inc., Tranche B-4 Term Loan, 
 
  
2.647% (LIBOR + 250 bps), 2/16/23 
$ 1,251,991 
1,063,781  
Alkermes, Inc., 2023 Term Loan, 2.41% (LIBOR + 
 
  
225 bps), 3/27/23 
1,055,802 
970,000  
Alphabet Holding Co., Inc. (aka Nature’s Bounty), 
 

 
First Lien Initial Term Loan, 3.647% (LIBOR +
 
  
350 bps), 9/26/24 
946,720 
1,200,000(i)  
Milano Acquisition Corp., Term Loan B, 8/17/27 
1,190,250 
1,501,318  
NMN Holdings III Corp., First Lien Closing Date 
 
  
Term Loan, 3.647% (LIBOR + 350 bps), 11/13/25 
1,441,265 
243,045  
Prestige Brands, Inc., Term B-4 Loan, 2.147% (LIBOR + 
 
  
200 bps), 1/26/24 
241,770 
1,422,850  
Sotera Health Holdings LLC, First Lien Initial Term 
 
  
Loan, 5.5% (LIBOR + 450 bps), 12/11/26 
1,419,293 
  Total Healthcare & Pharmaceuticals $ 7,547,091 

 Healthcare, Education & Childcare — 0.3% 
1,024,806  
ATI Holdings Acquisition, Inc., First Lien Initial Term 
 
  
Loan, 4.5% (LIBOR + 350 bps), 5/10/23 
$ 976,128 
 
The accompanying notes are an integral part of these financial statements.
78 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Healthcare, Education & Childcare — (continued) 
 
2,200,000  
Bausch Health Cos., Inc. (fka Valeant Pharmaceuticals 
 

 
International, Inc.), First Incremental Term
 
 
 
Loan, 2.901% (LIBOR + 275 bps), 11/27/25 
$ 2,154,625 
2,473,870  
Bausch Health Cos., Inc. (fka Valeant Pharmaceuticals 
 

 
International, Inc.), Initial Term Loan, 3.151%
 
 
 
(LIBOR + 300 bps), 6/2/25 
2,429,546 
4,844,922  
LifePoint Health, Inc. (fka Regionalcare Hospital 
 
 
 
Partners Holdings, Inc.), First Lien Term B Loan, 3.897% 
 
 
 
(LIBOR + 375 bps), 11/16/25 
4,716,726 
1,477,500  
Vizient, Inc., Term B-6 Loan, 2.147% (LIBOR + 
 
 
 
200 bps), 5/6/26 
1,451,644 
 
 Total Healthcare, Education & Childcare $ 11,728,669 
 
 Hotel, Gaming & Leisure — 0.1% 
 
1,203,131  
1011778 B.C. Unlimited Liability Co. (New Red 
 

 
Finance, Inc.) (aka Burger King/Tim Hortons),
 
 
 
Term B-4 Loan, 1.897% (LIBOR + 175 bps), 11/19/26 
$ 1,158,765 
1,992,446  
Boyd Gaming Corp., Refinancing Term B Loan, 2.356% 
 
 
 
(LIBOR + 225 bps), 9/15/23 
1,942,635 
1,989,854  
Flutter Entertainment Plc, USD Term Loan, 3.72% 
 
 
 
(LIBOR + 350 bps), 7/10/25 
1,992,755 
 
 Total Hotel, Gaming & Leisure $ 5,094,155 
 
 Insurance — 0.1% 
 
987,500  
Alliant Holdings Intermediate LLC, 2019 New Term 
 
 
 
Loan, 3.401% (LIBOR + 325 bps), 5/9/25 
$ 971,761 
68,909  
Alliant Holdings Intermediate LLC, Initial Term Loan, 
 
 
 
2.897% (LIBOR + 275 bps), 5/9/25 
67,053 
4,246,079  
Asurion LLC (fka Asurion Corp.), New B-7 Term Loan, 
 
 
 
3.147% (LIBOR + 300 bps), 11/3/24 
4,181,628 
382,498  
Confie Seguros Holding II Co., Term B Loan, 5.75% 
 
 
 
(LIBOR + 475 bps), 4/19/22 
370,784 
491,583  
Integro Parent, Inc., First Lien Initial Term Loan, 6.75% 
 
 
 
(LIBOR + 575 bps), 10/31/22 
484,209 
339,500  
USI, Inc. (fka Compass Investors, Inc.), 2017 New 
 
 
 
Term Loan, 3.22% (LIBOR + 300 bps), 5/16/24 
329,103 
 
 Total Insurance $ 6,404,538 
 
 Leasing — 0.1% 
 
1,144,959  
Avolon TLB Borrower 1 (US) LLC, Term B-3 Loan, 
 
 
 
2.5% (LIBOR + 175 bps), 1/15/25 
$ 1,120,628 
1,378,564  
Avolon TLB Borrower 1 (US) LLC, Term B-4 Loan, 
 
 
 
2.25% (LIBOR + 150 bps), 2/12/27 
1,326,221 
1,084,634  
Fly Funding II S.a.r.l., Replacement Term Loan, 1.99% 
 
 
 
(LIBOR + 175 bps), 8/11/25 
962,613 
975,000  
IBC Capital I, Ltd. (aka Goodpack, Ltd.), First Lien 
 
 
 
Tranche B-1 Term Loan, 3.983% (LIBOR + 
 
 
 
375 bps), 9/11/23 
918,937 
 
 Total Leasing $ 4,328,399 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 79
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Leisure & Entertainment — 0.0%† 
 
982,500(j)  
24 Hour Fitness Worldwide, Inc., Term Loan, 3.647% 
 
  
(LIBOR + 350 bps), 5/30/25 
$ 82,284 
725,625  
CityCenter Holdings LLC, Term B Loan, 3.0% (LIBOR + 
 
  
225 bps), 4/18/24 
698,505 
1,220,288  
Fitness International LLC, Term B Loan, 4.25% (LIBOR + 
 
  
325 bps), 4/18/25 
757,799 
  Total Leisure & Entertainment $ 1,538,588 
  Machinery — 0.1% 
 
96,197  
Clark Equipment Co. (aka Doosan Bobcat, Inc.), 
 

 
Repriced 2019 Term Loan, 1.97% (LIBOR +
 
  
175 bps), 5/18/24 
$ 93,406 
1,234,571  
CTC AcquiCo GmbH, Facility B2, 3.256% (LIBOR + 
 
  
300 bps), 3/7/25 
1,172,843 
140,069  
Gardner Denver, Inc., 2020 GDI Tranche B-2 Dollar 
 
  
Term Loan, 1.897% (LIBOR + 175 bps), 3/1/27 
135,779 
244,777  
NN, Inc., Tranche B Term Loan, 6.5% (LIBOR + 
 
  
575 bps), 10/19/22 
242,238 
1,540,221  
Shape Technologies Group, Inc., Initial Term Loan, 
 
  
3.151% (LIBOR + 300 bps), 4/21/25 
1,170,568 
2,731,406  
Terex Corp., 2019 US Term Loan Commitments, 
 
  
3.5% (LIBOR + 275 bps), 1/31/24 
2,676,778 
292,000  
Terex Corp., Incremental US Term Loan, 2.75% 
 
  
(LIBOR + 200 bps), 1/31/24 
283,240 
  Total Machinery $ 5,774,852 
  Media — 0.1% 
 
1,345,553  
CSC Holdings LLC (fka CSC Holdings, Inc. 
 
  
(Cablevision)), October 2018 Incremental Term Loan, 
 
  
2.402% (LIBOR + 225 bps), 1/15/26 
$ 1,305,467 
2,175,000  
Ziggo Financing Partnership, Term Loan I Facility, 
 
  
2.652% (LIBOR + 250 bps), 4/30/28 
2,102,198 
  Total Media $ 3,407,665 
  Metals & Mining — 0.1% 
 
904,787  
Atkore International, Inc., First Lien Initial Incremental 
 
  
Term Loan, 3.75% (LIBOR + 275 bps), 12/22/23 
$ 902,751 
772,710  
BWay Holding Co., Initial Term Loan, 3.523% (LIBOR + 
 
  
325 bps), 4/3/24 
731,418 
215,625  
Oxbow Carbon LLC, First Lien Tranche B Term Loan, 
 
  
3.897% (LIBOR + 375 bps), 1/4/23 
212,391 
1,826,944  
Phoenix Guarantor, Inc. (aka Brightspring), First Lien 
 
  
Tranche B-1 Term Loan, 3.401% (LIBOR + 
 
  
325 bps), 3/5/26 
1,787,360 
  Total Metals & Mining $ 3,633,920 
 
The accompanying notes are an integral part of these financial statements.
80 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 Oil & Gas — 0.1% 
 
3,570,258  
Centurion Pipeline Co. LLC (fka Lotus Midstream LLC), 
 
 
 
Initial Term Loan, 3.397% (LIBOR + 
 
 
 
325 bps), 9/29/25 
$ 3,534,556 
 
 Total Oil & Gas $ 3,534,556 
 
 Personal, Food & Miscellaneous Services — 0.0%† 
 
1,215,813  
Option Care Health, Inc., Term B Loan, 4.647% 
 
 
 
(LIBOR + 450 bps), 8/6/26 
$ 1,207,707 
 
 Total Personal, Food & Miscellaneous Services $ 1,207,707 
 
 Printing & Publishing — 0.0%† 
 
1,201,725  
Red Ventures LLC (New Imagitas, Inc.), First Lien 
 
 
 
Term B-2 Loan, 2.647% (LIBOR + 250 bps), 11/8/24 
$ 1,155,408 
 
 Total Printing & Publishing $ 1,155,408 
 
 Professional & Business Services — 0.2% 
 
990,000  
Clear Channel Outdoor Holdings, Inc., Term B Loan, 
 
 
 
3.761% (LIBOR + 350 bps), 8/21/26 
$ 905,850 
2,929,825  
Elanco Animal Health, Inc., Term Loan, 1.905% (LIBOR + 
 
 
 
175 bps), 8/1/27 
2,853,702 
1,234,375  
MYOB US Borrower LLC, First Lien Initial US Term Loan, 
 
 
 
4.147% (LIBOR + 400 bps), 5/6/26 
1,211,230 
2,000,000  
Nielsen Finance LLC, Dollar Term B-5 Loan, 4.75% 
 
 
 
(LIBOR + 375 bps), 6/4/25 
2,000,000��
750,000(i)  
Pre-Paid Legal Services, Inc. (aka LegalShield), 
 
 
 
Incremental Term Loan, 5/1/25 
744,375 
1,000,000  
Victory Capital Holdings, Inc., Tranche B-1 Term Loan, 
 
 
 
2.799% (LIBOR + 250 bps), 7/1/26 
987,500 
 
 Total Professional & Business Services $ 8,702,657 
 
 Retail — 0.2% 
 
1,600,000  
Asplundh Tree Expert LLC, Initial Term Loan, 2.655% 
 
 
 
(LIBOR + 250 bps), 9/7/27 
$ 1,600,333 
727,500  
Bass Pro Group LLC, Initial Term Loan, 5.75% (LIBOR + 
 
 
 
500 bps), 9/25/24 
723,271 
2,450,000  
HD Supply, Inc., Term B-5 Loan, 1.897% (LIBOR + 
 
 
 
175 bps), 10/17/23 
2,446,428 
2,372,514  
KFC Holding Co. (aka Yum! Brands), 2018 Term B 
 
 
 
Loan, 1.9% (LIBOR + 175 bps), 4/3/25 
2,334,172 
 
 Total Retail $ 7,104,204 
 
 Securities & Trusts — 0.0%† 
 
319,772  
RPI Intermediate Finance Trust, Term B-1 Term Facility, 
 
 
 
1.897% (LIBOR + 175 bps), 2/11/27 
$ 319,372 
 
 Total Securities & Trusts $ 319,372 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 81
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  Telecommunications — 0.4% 
 
5,022,100  
CenturyLink, Inc., Term B Loan, 2.397% (LIBOR + 
 
  
225 bps), 3/15/27 
$ 4,834,218 
2,487,251  
Ciena Corp., Refinancing Term Loan, 1.906% (LIBOR + 
 
  
175 bps), 9/26/25 
2,475,203 
2,432,003  
Go Daddy Operating Co. LLC (GD Finance Co., Inc.), 
 
  
Tranche B-2 Term Loan, 1.897% (LIBOR + 
 
  
175 bps), 2/15/24 
2,384,883 
1,246,875  
Go Daddy Operating Co. LLC (GD Finance Co., Inc.), 
 
  
Tranche B-3 Term Loan, 2.647% (LIBOR + 
 
  
250 bps), 8/10/27 
1,231,289 
3,990,234  
Level 3 Financing, Inc., Tranche B 2027 Term Loan, 
 
  
1.897% (LIBOR + 175 bps), 3/1/27 
3,869,813 
1,484,673  
Virgin Media Bristol LLC, N Facility, 2.652% (LIBOR + 
 
  
250 bps), 1/31/28 
1,445,700 
1,025,000(i)  
Virgin Media Bristol LLC, Term Loan Q, 1/31/29 
1,009,991 
  Total Telecommunications $ 17,251,097 
  Transportation — 0.0%† 
 
2,407,125  
Envision Healthcare Corp., Initial Term Loan, 3.897% 
 
  
(LIBOR + 375 bps), 10/10/25 
$ 1,736,139 
63,408(k)  
Syncreon Group BV, Second Out Term Loan, 7.0% 
 
  
(6.0% PIK or 1.0% cash), 4/1/25 
59,445 
  Total Transportation $ 1,795,584 
  Utilities — 0.1% 
 
1,095,013  
APLP Holdings, Ltd. Partnership, Term Loan, 3.5% 
 
  
(LIBOR + 250 bps), 4/14/25 
$ 1,094,556 
753,688  
Calpine Construction Finance Co., LP, Term B Loan, 
 
  
2.147% (LIBOR + 200 bps), 1/15/25 
731,831 
495,000  
Calpine Corp., Term Loan, 2.147% (LIBOR + 
 
  
200 bps), 8/12/26 
482,183 
1,994,635  
Compass Power Generation, LLC, Tranche B-1 Term 
 
  
Loan, 4.5% (LIBOR + 350 bps), 12/20/24 
1,963,469 
471,819  
Eastern Power LLC (Eastern Covert Midco LLC) (aka 
 

 
TPF II LC LLC), Term Loan, 4.75% (LIBOR +
 
  
375 bps), 10/2/25 
469,129 
565,759  
Vistra Operations Co. LLC (fka Tex Operations Co. 
 
  
LLC), 2018 Incremental Term Loan, 1.897% (LIBOR + 
 
  
175 bps), 12/31/25 
558,333 
  Total Utilities $ 5,299,501 
  TOTAL SENIOR SECURED FLOATING RATE 
 
  LOAN INTERESTS 
 
  
(Cost $183,630,008) 
$ 177,286,910 
 
The accompanying notes are an integral part of these financial statements.
82 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
 
 U.S. GOVERNMENT AND AGENCY 
 

 OBLIGATIONS — 3.8% of Net Assets 
7,317(a)  Fannie Mae, 3.371% (1 Year CMT Index + 
 
 
 210 bps), 9/1/32 $ 7,487 
179(a)  Fannie Mae, 3.624% (1 Year CMT Index + 
 
 
 232 bps), 11/1/23 180 
6,731(a)  Fannie Mae, 3.733% (2 Month USD LIBOR + 
 
 
 168 bps), 1/1/48 6,872 
6,915(a)  Fannie Mae, 3.766% (1 Year CMT Index + 
 
 
 219 bps), 10/1/32 6,929 
6,132(a)  Fannie Mae, 3.795% (1 Year CMT Index + 
 
 
 217 bps), 2/1/34 6,098 
541(a)  Federal Home Loan Mortgage Corp., 3.07% (1 Year 
 
 
 CMT Index + 230 bps), 10/1/23 541 
3,824(a)  Federal Home Loan Mortgage Corp., 4.125% (2 Month 
 
 
 USD LIBOR + 200 bps), 11/1/33 3,852 
948(a)  Federal Home Loan Mortgage Corp., 4.371% (5 Year 
 
 
 CMT Index + 212 bps), 6/1/35 961 
1,153(a)  Government National Mortgage Association II, 3.0% 
 
 
 (1 Year CMT Index + 150 bps), 1/20/22 1,164 
25,000,000(a)  U.S. Treasury Floating Rate Notes, 0.254% (3 Month U.S. 
 
 
 Treasury Bill Money Market Yield + 15 bps), 1/31/22 25,040,858 
25,000,000(a)  U.S. Treasury Floating Rate Notes, 0.32% (3 Month U.S. 
 
 
 Treasury Bill Money Market Yield + 22 bps), 7/31/21 25,045,777 
119,000,000(a)  U.S. Treasury Floating Rate Notes, 0.4% (3 Month U.S. 
 
 
 Treasury Bill Money Market Yield + 30 bps), 10/31/21 119,384,656 
11,700,000  
U.S. Treasury Note, 2.25%, 7/31/21 
11,907,035 
 
 TOTAL U.S. GOVERNMENT AND AGENCY OBLIGATIONS 
 
 
 
(Cost $181,394,860) 
$ 181,412,410 
 
 TEMPORARY CASH INVESTMENTS — 4.1% 
 
 
 of Net Assets 
 
 
 CERTIFICATES OF DEPOSIT — 0.4% 
 
6,100,000(a)  Lloyds Bank Corporate Markets Plc, 0.822% (3 Month 
 
 
 USD LIBOR + 55 bps), 7/19/21 $ 6,116,009 
6,375,000  Natixis, 1.93%, 11/13/20 6,389,124 
9,200,000  Skandinaviska Enskilda Banken, 0.24%, 10/1/20 9,200,038 
 
 
 
$ 21,705,171 
 
 COMMERCIAL PAPERS — 2.1% 
 
2,900,000  Bat Capital Co., 0.25%, 10/5/20 $ 2,899,936 
9,200,000  CenterPoint Energy, Inc., 0.12%, 10/1/20 9,199,972 
9,200,000  Cigna Holding Co., 0.2%, 10/9/20 9,199,627 
1,450,000  DNB Bank ASA, 0.12%, 10/13/20 1,449,948 
9,200,000  Enable Midstream Partners, 0.55%, 10/1/20 9,199,898 
2,500,000  Enel Finance America LLC, 0.28%, 10/6/20 2,499,933 
18,400,000  Energy Transfer LP, 0.62%, 10/1/20 18,399,796 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 83
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
    
Principal  
 
 
Amount  
 
 
USD ($)  
 
Value 
  COMMERCIAL PAPERS — (continued) 
 
9,200,000  Eni Finance USA, Inc., 0.12%, 10/1/20 $ 9,199,964 
9,210,000  General Motors, Inc., 0.5%, 10/1/20 9,209,895 
5,600,000  LG&E & KU Energy LLC, 0.16%, 10/9/20 5,599,769 
18,400,000  Prudential Funding LLC, 0.11%, 10/1/20 18,399,965 
4,000,000  Santander UK, 0.2%, 10/2/20 3,999,981 
  
 
$ 99,258,684 
  REPURCHASE AGREEMENTS — 1.6% 
 
18,980,000  $18,980,000 Merrill Lynch, Pierce, Fenner & Smith, Inc., 
 

 
0.07%, dated 9/30/20 plus accrued interest on
 
  10/1/20 collateralized by $19,359,600 
 

 
Government National Mortgage Association,
 
  2.0%, 9/20/50. $ 18,980,000 
18,980,000  $18,980,000 RBC Capital Markets LLC, 0.08%, 
 
  dated 9/30/20 plus accrued interest on 10/1/20 
 
  collateralized by the following: 
 

 
$1,245,165 Freddie Mac Giant, 4.0%, 2/1/47
 

 
$18,114,478 Government National Mortgage
 
  Association, 2.0%-4.0%, 2/20/48-9/20/50. 18,980,000 
18,980,000  $18,980,000 ScotiaBank, 0.07%, dated 9/30/20 
 

 
plus accrued interest on 10/1/20 collateralized
 
  by the following: 
 

 
$12,120,387 Freddie Mac Giant, 3.5%, 5/1/50
 
  $7,239,364 U.S. Treasury Notes, 2.3, 11/15/27. 18,980,000 
9,490,000  $9,490,000 TD Securities USA LLC, 0.06%, dated 
 

 
9/30/20 plus accrued interest on 10/1/20
 
  collateralized by $9,679,867 U.S. Treasury Notes, 
 
  2.0%, 2/15/50. 9,490,000 
9,490,000  $9,490,000 TD Securities USA LLC, 0.08%, 
 
  dated 9/30/20 plus accrued interest on 10/1/20 
 
  collateralized by $9,679,867 U.S. Treasury Notes, 
 
  2.0%, 2/15/50. 9,490,000 
  
 
$ 75,920,000 
  TOTAL TEMPORARY CASH INVESTMENTS 
 
  
(Cost $196,879,167) 
$ 196,883,855 
  TOTAL INVESTMENTS IN UNAFFILIATED ISSUERS — 100.5% 
 
  
(Cost $4,812,348,018) 
$4,765,467,894 
  OTHER ASSETS AND LIABILITIES — (0.5)% $ (21,644,793) 
  NET ASSETS — 100.0% $4,743,823,101 
 
The accompanying notes are an integral part of these financial statements.
84 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

  
bps 
Basis Points. 
CMT 
Constant Maturity Treasury. 
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. 
(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 September 30, 2020, the value of these securities amounted to $1,962,033,920, or 41.4% of net assets. 
† 
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 September 30, 2020. 
Security that used significant unobservable inputs to determine its value. 
(a) 
Floating rate note. Coupon rate, reference index and spread shown at September 30, 2020. 
(b) 
The interest rate is subject to change periodically. The interest rate and/or reference index and spread shown at September 30, 2020. 
(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 September 30, 2020. 
(d) 
Security issued with a zero coupon. Income is recognized through accretion of discount. 
(e) 
Issued as participation notes. 
(f) 
Non-income producing security. 
(g) 
Issued as preference shares. 
(h) 
Consists of Revenue Bonds unless otherwise indicated. 
(i) 
This term loan will settle after September 30, 2020, at which time the interest rate will be determined. 
(j) 
Security is in default. 
(k) 
Payment-in-kind (PIK) security which may pay interest in the form of additional 
principal amount. 
Securities are restricted as to resale. 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 85
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
        
Restricted Securities Acquisition date  Cost  Value 
Adare Re 2020 12/30/2019  
$
2,511,250
  
$
2,606,675
 
Ailsa Re 2019 6/7/2019   
2,750,000
   
2,818,475
 
Akibare Re 3/22/2018   
250,000
   
247,275
 
Akibare Re 3/22/2018   
500,000
   
496,400
 
Alamo Re II 5/29/2020   
2,500,000
   
2,582,500
 
Alturas Re 2019-1 12/20/2018   
2,000
   
9,819
 
Alturas Re 2019-2 12/19/2018   
36,448
   
194,498
 
Aozora Re 3/20/2017   
1,500,000
   
1,500,000
 
Artex Sac, Ltd. Bantry Re, 2016 2/6/2019   
201,500
   
201,500
 
Bantry Re 2017 2/6/2019   
472,246
   
472,200
 
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   
975,468
   
623,124
 
Berwick Re 2019-1 12/31/2018   
437,104
   
437,135
 
Blue Lotus Re 2018 12/20/2017   
   
65,550
 
Bonanza RE 2/13/2020   
1,500,000
   
1,500,750
 
Bowline Re 6/17/2020   
242,878
   
249,575
 
Bowline Re 3/12/2019   
250,000
   
253,625
 
Caelus Re V 5/4/2018   
750,000
   
741,675
 
Caelus Re V 5/4/2018   
500,000
   
499,000
 
Caelus Re V 4/27/2017   
625,000
   
568,750
 
Caelus Re VI 2/20/2020   
750,000
   
749,250
 
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   
496,780
   
261,880
 
Cypress Re 2017 1/24/2017   
3,361
   
18,200
 
Denning Re 2019 8/8/2019   
2,941,866
   
3,081,638
 
Dingle Re 2019 3/4/2019   
455,946
   
510,263
 
Dingle Re 2020 2/13/2020   
232,875
   
253,771
 
Eden Re II 12/14/2018   
4,000
   
32,466
 
Eden Re II 1/22/2019   
35,797
   
298,987
 
Eden Re II 12/15/2017   
4,482
   
48,741
 
Eden Re II 
1/23/2018   
2,621
   
70,950
 
First Coast Re II Pte 
6/15/2020   
680,818
   
701,330
 
FloodSmart Re 
4/10/2019   
500,000
   
496,500
 
Formby Re 2018 
7/9/2018   
296,099
   
353,832
 
Fortius Re II 
7/13/2017   
500,000
   
500,950
 
Galilei Re 
1/4/2017   
1,143,994
   
1,150,000
 
Galilei Re 
1/4/2017   
2,299,292
   
2,301,150
 
Galilei Re 
1/4/2017   
1,250,000
   
1,250,000
 
Gleneagles Re 2016 
1/14/2016   
   
40,560
 
Gullane Re 2018 
3/26/2018   
2,018,740
   
2,168,623
 
Harambee Re 2018 
12/19/2017   
156,092
   
22,400
 
Harambee Re 2019 
12/20/2018   
   
46,000
 
Hypatia Ltd. 
7/10/2020   
1,000,000
   
1,046,500
 
Hypatia Ltd. 
7/10/2020   
2,500,000
   
2,610,750
 
Integrity Re 
4/19/2018   
2,492,626
   
2,453,000
 
International Bank for 
 
        
Reconstruction & Development 2/28/2020   
500,000
   
499,450
 
International Bank for 
 
        
Reconstruction & Development 2/2/2018   
1,800,000
   
1,792,800
 
 
The accompanying notes are an integral part of these financial statements.
86 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

        
Restricted Securities Acquisition date  Cost  Value 
International Bank for 
 
      
Reconstruction & Development 2/2/2018  
$
1,300,000
  
$
1,294,540
 
International Bank for 
 
        
Reconstruction & Development 2/2/2018   
700,000
   
702,380
 
International Bank for 
 
        
Reconstruction & Development 2/28/2020   
500,000
   
499,450
 
Kendall Re 
6/12/2020   
490,004
   
500,500
 
Kilimanjaro II Re 
6/12/2020   
342,037
   
350,350
 
Kilimanjaro II Re 
4/6/2017   
1,700,000
   
1,698,300
 
Kilimanjaro Re 
6/12/2020   
244,584
   
251,375
 
Kizuna Re II 
3/16/2018   
746,616
   
747,900
 
Kizuna Re II 
6/5/2020   
246,812
   
249,250
 
Leven Re 2020 
1/29/2020   
3,130,075
   
3,273,283
 
Limestone Re 2016-1 
12/15/2016   
1,980
   
70
 
Limestone Re 2016-1 
12/15/2016   
3,300
   
116
 
Limestone Re 2018 
6/20/2018   
2,000
   
68,353
 
Limestone Re 2019-2 
6/20/2018   
223,000
   
388,912
 
Lion Rock Re 2019 
12/17/2018   
   
39,100
 
Long Point Re III 
5/17/2018   
1,250,000
   
1,250,125
 
Lorenz Re 2018 
6/26/2018   
1,073,131
   
109,600
 
Lorenz Re 2019 
6/26/2019   
892,789
   
265,397
 
Matterhorn Re 
6/25/2020   
2,213,414
   
2,263,000
 
Matterhorn Re 
4/30/2020   
242,423
   
243,125
 
Matterhorn Re 
4/30/2020   
250,000
   
254,875
 
Matterhorn Re 
1/29/2020   
1,494,179
   
1,503,450
 
Matterhorn Re 
6/5/2020   
394,638
   
401,080
 
Matterhorn Re 
6/25/2020   
2,250,000
   
2,281,500
 
Matterhorn Re 2019-1 
6/14/2019   
494,541
   
495,700
 
Matterhorn Re 2020-1 
12/20/2019   
2,000,000
   
2,004,600
 
Merion Re 2018-2 
12/28/2017   
3,000,000
   
3,232,500
 
Nakama Re 
9/21/2016   
697,068
   
697,970
 
NCM Re 2019 
12/27/2018   
5,323
   
113,623
 
Oakmont Re 2017 
5/10/2017   
   
14,700
 
Oakmont Re 2019 
5/21/2019   
1,454,186
   
1,730,780
 
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   
29,397
   
58,345
 
Pangaea Re 2019-3 
7/25/2019   
88,238
   
105,799
 
Port Royal Re 2019 
5/20/2019   
3,682,624
   
4,045,158
 
Portrush Re 2017 
6/12/2017   
613,588
   
510,480
 
Residential Reinsurance 2016 
6/12/2020   
1,216,792
   
1,252,375
 
Residential Reinsurance 2016 
11/3/2016   
2,347,078
   
2,350,470
 
Residential Reinsurance 2017 
4/19/2017   
2,099,929
   
2,104,410
 
Residential Reinsurance 2017 
11/3/2017   
2,900,000
   
2,869,550
 
Residential Reinsurance 2018 
4/30/2018   
1,250,000
   
1,237,625
 
Residential Reinsurance 2019 
5/8/2019   
500,000
   
494,250
 
Residential Reinsurance 2020 
5/27/2020   
500,000
   
503,900
 
Resilience Re 
4/13/2017   
6,535
   
200
 
Resilience Re 
2/8/2017   
1,209
   
250
 
Sanders Re 
6/12/2020   
240,308
   
246,600
 
Sanders RE II Ltd. 
5/20/2020   
250,000
   
254,900
 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 87
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
        
Restricted Securities Acquisition date  Cost  Value 
Scotscraig Re 2020 1/29/2020  
$
2,031,469
  
$
2,239,890
 
Sector Re V 1/1/2020   
1,600,000
   
1,682,001
 
Sector Re V 12/4/2018   
1,311,532
   
801,252
 
Sector Re V, Series 9, Class A 4/23/2019   
800,000
   
337,059
 
Sector Re V, Series 9, Class G 5/1/2019   
1,861
   
49,159
 
Spectrum Capital, Ltd. 6/12/2020   
983,598
   
1,002,400
 
St. Andrews Re 2017-1 1/5/2017   
84,685
   
84,750
 
St. Andrews Re 2017-4 3/31/2017   
   
171,018
 
Tailwind Re 12/20/2017   
3,349,219
   
3,396,900
 
Thopas Re 2018 12/12/2017   
120,110
   
 
Thopas Re 2019 12/21/2018   
511,491
   
447,600
 
Ursa Re 11/21/2017   
600,000
   
599,400
 
Ursa Re 9/7/2018   
992,479
   
998,700
 
Ursa Re 11/20/2019   
744,320
   
749,550
 
Versutus Re 2017 1/5/2017   
172,227
   
 
Versutus Re 2018 1/31/2018   
67,925
   
38,000
 
Versutus Re 2019-A 
1/28/2019   
   
78,900
 
Versutus Re 2019-B 
12/24/2018   
   
64,140
 
Viribus Re 2018 
12/22/2017   
99,253
   
27,300
 
Viribus Re 2019 
12/27/2018   
   
100,250
 
Vita Capital VI, Ltd. 
2/12/2020   
1,747,991
   
1,487,500
 
Vitality Re VIII 
2/13/2020   
249,605
   
248,500
 
Vitality Re VIII 
1/31/2020   
999,884
   
991,500
 
Vitality Re X 
1/23/2020   
3,000,000
   
2,980,500
 
Vitality Re X 
1/31/2020   
1,748,641
   
1,736,875
 
Vitality Re X 
2/3/2020   
3,496,603
   
3,480,750
 
Vitality Re XI 
1/23/2020   
1,242,855
   
1,240,000
 
Woburn Re 2018 
3/20/2018   
642,700
   
158,914
 
Woburn Re 2019 
1/30/2019   
247,877
   
275,802
 
Total Restricted Securities 
 
     
$
107,850,821
 
% of Net assets 
 
      
2.3
%
 
Principal amounts are denominated in U.S. dollars (“USD”) unless otherwise noted.
Purchases and sales of securities (excluding temporary cash investments) for the six months ended September 30, 2020 were as follows:
       
 
 Purchases  Sales 
Long-Term U.S. Government Securities 
 
$
50,068,583
  
$
394,060,627
 
Other Long-Term Securities 
 
$
1,065,469,877
  
$
1,146,988,978
 
 
The accompanying notes are an integral part of these financial statements.
88 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

The Fund is permitted to engage in purchase and sale transactions (“cross trades”) with certain funds and accounts for which Amundi Pioneer Asset Management, 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 six months ended September 30, 2020, the Fund engaged in purchases of $8,903,060 and sales of $194,855 pursuant to these procedures, which resulted in a net realized gain/(loss) of $(11,765).
At September 30, 2020, the net unrealized depreciation on investments based on cost for federal tax purposes of $4,824,779,322 was as follows:
    
Aggregate gross unrealized appreciation for all investments in which    
there is an excess of value over tax cost  
$
19,428,422
 
Aggregate gross unrealized depreciation for all investments in which     
there is an excess of tax cost over value   
(78,739,850
)
Net unrealized depreciation  
$
(59,311,428
)
 
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 – 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 | Semiannual Report | 9/30/20 89
 

Schedule of Investments | 9/30/20
(unaudited) (continued)
The following is a summary of the inputs used as of September 30, 2020, in valuing the Fund’s investments:
             
 
 Level 1  Level 2  Level 3  Total 
Asset Backed Securities 
 
$
  
$
1,562,355,864
  
$
  
$
1,562,355,864
 
Collateralized Mortgage 
                
Obligations   
   
687,457,356
   
   
687,457,356
 
Commercial Mortgage-Backed 
                
Securities 
  
   
538,842,949
   
   
538,842,949
 
Corporate Bonds 
  
   
1,288,253,059
   
   
1,288,253,059
 
Foreign Government Bond 
  
   
25,055,751
   
   
25,055,751
 
Insurance-Linked Securities 
                
Collateralized Reinsurance                 
Earthquakes - California   
   
   
2,606,675
   
2,606,675
 
Multiperil - Massachusetts   
   
   
3,081,638
   
3,081,638
 
Multiperil - U.S.   
   
   
4,809,192
   
4,809,192
 
Multiperil - U.S. & Canada   
   
   
3,273,283
   
3,273,283
 
Multiperil - U.S. Regional   
   
   
2,818,475
   
2,818,475
 
Multiperil - Worldwide   
   
   
407,748
   
407,748
 
Windstorm - Florida   
   
   
864,312
   
864,312
 
Windstorm - U.S. Regional   
   
   
1,745,480
   
1,745,480
 
Industry Loss Warranties                 
Multiperil - U.S.   
   
   
2,239,890
   
2,239,890
 
Reinsurance Sidecars                 
Multiperil - U.S.   
   
   
595,970
   
595,970
 
Multiperil - Worldwide   
   
   
13,300,803
   
13,300,803
 
All Other Insurance-Linked                 
Securities   
   
72,107,355
   
   
72,107,355
 
Municipal Bond 
  
   
68,919
   
   
68,919
 
Senior Secured Floating 
                
Rate Loan Interests   
   
177,286,910
   
   
177,286,910
 
U.S. Government and 
                
Agency Obligations   
   
181,412,410
   
   
181,412,410
 
Certificates of Deposit 
  
   
21,705,171
   
   
21,705,171
 
Commercial Papers 
  
   
99,258,684
   
   
99,258,684
 
Repurchase Agreements 
  
   
75,920,000
   
   
75,920,000
 
Total Investments in Securities  $  $4,729,724,428  $35,743,466  $4,765,467,894 
 
The accompanying notes are an integral part of these financial statements.
90 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

The following is a reconciliation of assets valued using significant unobservable inputs (Level 3):
    
 
 Insurance- 
 
 Linked 
 
 Securities 
Balance as of 3/31/20 
 
$
61,676,226
 
Realized gain (loss)(1) 
  
(1,493,565
)
Change in unrealized depreciation(2) 
  
(332,728
)
Accrued discounts/premiums 
  
 
Purchases 
  
 
Sales 
  
(23,625,717
)
Transfers in to Level 3* 
  
 
Transfers out of Level 3* 
  
(480,750
)
Balance as of 9/30/20  $35,743,466 
 
  
(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 six months ended September 30, 2020, securities with an aggregate market value of $480,750 was transferred from Level 3 to Level 2, due to valuing the security using observable inputs. There were no other transfers between Levels 1, 2 and 3. 
    
Net change in unrealized appreciation (depreciation) of Level 3 investments still    
held and considered Level 3 at September 30, 2020:  
$
(1,035,419
)
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 91
 

Statement of Assets and Liabilities | 9/30/20
(unaudited)
    
ASSETS:    
Investments in unaffiliated issuers, at value (cost $4,812,348,018)  
$
4,765,467,894
 
Cash   
32,812,938
 
Receivables —     
Investment securities sold   
22,693,386
 
Fund shares sold   
22,406,583
 
Interest   
7,289,931
 
Other assets   
176,852
 
Total assets  $4,850,847,584 
LIABILITIES:     
Payables —     
Investment securities purchased  
$
80,796,998
 
Fund shares repurchased   
24,499,026
 
Distributions   
446,453
 
Trustees’ fees   
11,885
 
Unrealized depreciation on unfunded loan commitments   
12,310
 
Due to affiliates   
277,403
 
Accrued expenses   
980,408
 
Total liabilities  $107,024,483 
NET ASSETS:     
Paid-in capital  
$
5,045,282,404
 
Distributable earnings (loss)   
(301,459,303
)
Net assets  $4,743,823,101 
NET ASSET VALUE PER SHARE:     
No par value (unlimited number of shares authorized) 
    
Class A (based on $1,635,492,635/170,177,417 shares)  
$
9.61
 
Class C (based on $262,256,938/27,275,134 shares)  
$
9.62
 
Class C2 (based on $20,970,417/2,180,546 shares)  
$
9.62
 
Class K (based on $265,748,854/27,570,153 shares)  
$
9.64
 
Class Y (based on $2,559,354,257/265,854,257 shares)  
$
9.63
 
 
The accompanying notes are an integral part of these financial statements.
92 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

Statement of Operations (unaudited)
FOR THE SIX MONTHS ENDED 9/30/20
       
INVESTMENT INCOME:       
Interest from unaffiliated issuers  
$
46,812,600
    
Dividends from unaffiliated issuers   
1,942,416
    
Total investment income      $48,755,016 
EXPENSES:         
Management fees  
$
7,610,612
     
Administrative expense   
570,568
     
Transfer agent fees         
Class A   
202,758
     
Class C   
38,051
     
Class C2   
5,313
     
Class K   
401
     
Class Y   
982,428
     
Distribution fees         
Class A   
1,617,815
     
Class C   
703,762
     
Class C2   
53,311
     
Shareowner communications expense   
76,513
     
Custodian fees   
74,418
     
Registration fees   
167,838
     
Professional fees   
146,150
     
Printing expense   
28,331
     
Pricing fees   
112,407
     
Trustees’ fees   
160,193
     
Insurance expense   
8,801
     
Miscellaneous   
90,612
     
Total expenses      
$
12,650,282
 
Net investment income      $36,104,734 
REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS:     
Net realized gain (loss) on:         
Investments in unaffiliated issuers      
$
(31,243,408
)
Change in net unrealized appreciation (depreciation) on:         
Investments in unaffiliated issuers  
$
224,490,423
     
Unfunded loan commitments   
110,019
  
$
224,600,442
 
Net realized and unrealized gain (loss) on investments      $193,357,034 
Net increase in net assets resulting from operations      $229,461,768 
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 93
 

Statements of Changes in Net Assets
       
 
 Six Months    
 
 Ended  Year 
 
 9/30/20  Ended 
 
 (unaudited)  3/31/20 
FROM OPERATIONS:       
Net investment income (loss) 
 
$
36,104,734
  
$
161,673,331
 
Net realized gain (loss) on investments 
  
(31,243,408
)
  
(167,329,917
)
Change in net unrealized appreciation (depreciation) 
        
on investments   
224,600,442
   
(254,161,235
)
Net increase (decrease) in net assets resulting         
from operations  $229,461,768  $(259,817,821)
DISTRIBUTIONS TO SHAREOWNERS:         
Class A ($0.08 and $0.27 per share, respectively)  
$
(13,856,174
)
 
$
(48,393,422
)
Class C ($0.07 and $0.24 per share, respectively)   
(2,002,457
)
  
(9,350,830
)
Class C2 ($0.07 and $0.24 per share, respectively)   
(151,523
)
  
(292,948
)
Class K ($0.09 and $0.30 per share, respectively)   
(2,598,006
)
  
(10,737,706
)
Class Y ($0.09 and $0.29 per share, respectively)   
(25,265,911
)
  
(105,798,339
)
Total distributions to shareowners  
$
(43,874,071
)
 
$
(174,573,245
)
FROM FUND SHARE TRANSACTIONS:         
Net proceeds from sales of shares 
 
$
1,108,668,710
  
$
5,510,392,928
 
Reinvestment of distributions 
  
39,928,797
   
158,619,800
 
Cost of shares repurchased 
  
(1,794,751,386
)
  
(5,915,746,371
)
Net decrease in net assets resulting from         
Fund share transactions  
$
(646,153,879
)
 
$
(246,733,643
)
Net decrease in net assets  $(460,566,182) $(681,124,709)
NET ASSETS:         
Beginning of period 
 
$
5,204,389,283
  
$
5,885,513,992
 
End of period 
 $4,743,823,101  $5,204,389,283 
 
The accompanying notes are an integral part of these financial statements.
94 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

             
 
 Six Months  Six Months       
 
 Ended  Ended       
 
 9/30/20  9/30/20  Year Ended  Year Ended 
 
 Shares  Amount  3/31/20  3/31/20 
 
 (unaudited)  (unaudited)  Shares  Amount 
Class A             
Shares sold 
  
40,555,781
  
$
385,149,078
   
207,659,616
  
$
2,059,762,141
 
Reinvestment of 
                
distributions   
1,413,578
   
13,420,528
   
4,724,639
   
46,618,899
 
Less shares repurchased 
  
(47,635,400
)
  
(451,491,755
)
  
(188,391,509
)
  
(1,839,757,207
)
Net increase                 
(decrease)   
(5,666,041
)
 
$
(52,922,149
)
  
23,992,746
  
$
266,623,833
 
Class C                 
Shares sold 
  
1,401,407
  
$
13,322,343
   
11,059,054
  
$
109,569,322
 
Reinvestment of 
                
distributions   
209,580
   
1,989,819
   
945,924
   
9,341,514
 
Less shares repurchased 
  
(6,738,547
)
  
(63,916,005
)
  
(22,585,668
)
  
(221,897,172
)
Net decrease   
(5,127,560
)
 
$
(48,603,843
)
  
(10,580,690
)
 
$
(102,986,336
)
Class C2                 
Shares sold 
  
275,467
  
$
2,620,229
   
1,697,084
  
$
16,812,541
 
Reinvestment of 
                
distributions   
1,566
   
14,873
   
7,983
   
78,821
 
Less shares repurchased 
  
(360,849
)
  
(3,448,556
)
  
(309,176
)
  
(2,999,390
)
Net increase                 
(decrease)   
(83,816
)
 
$
(813,454
)
  
1,395,891
  
$
13,891,972
 
Class K                 
Shares sold 
  
2,412,091
  
$
22,680,643
   
16,044,359
  
$
159,364,345
 
Reinvestment of 
                
distributions   
270,854
   
2,579,517
   
1,078,075
   
10,665,224
 
Less shares repurchased 
  
(3,587,390
)
  
(34,018,593
)
  
(16,312,518
)
  
(159,929,239
)
Net increase                 
(decrease)   
(904,445
)
 
$
(8,758,433
)
  
809,916
  
$
10,100,330
 
Class Y                 
Shares sold 
  
72,160,273
  
$
684,896,417
   
319,898,241
  
$
3,164,884,579
 
Reinvestment of 
                
distributions   
2,305,513
   
21,924,060
   
9,300,699
   
91,915,342
 
Less shares repurchased 
  
(131,118,276
)
  
(1,241,876,477
)
  
(376,494,340
)
  
(3,691,163,363
)
Net decrease   
(56,652,490
)
 
$
(535,056,000
)
  
(47,295,400
)
 
$
(434,363,442
)
 
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 95
 

Financial Highlights
                   
 
 Six Months                
 
 Ended  Year  Year  Year  Year  Year 
 
 9/30/20  Ended  Ended  Ended  Ended  Ended 
 
 (unaudited)  3/31/20  3/31/19  3/31/18  3/31/17*  3/31/16* 
Class A                   
Net asset value, beginning of period 
 
$
9.26
  
$
9.92
  
$
9.95
  
$
9.99
  
$
9.92
  
$
10.00
 
Increase (decrease) from investment operations: 
                        
Net investment income (loss) (a)  
$
0.07
  
$
0.25
  
$
0.26
  
$
0.18
  
$
0.16
  
$
0.10
 
Net realized and unrealized gain (loss) on investments   
0.36
   
(0.64
)
  
(0.03
)
  
(0.03
)
  
0.08
   
(0.06
)
Net increase (decrease) from investment operations  $0.43  $(0.39) $0.23  $0.15  $0.24  $0.04 
Distributions to shareowners: 
                        
Net investment income  
$
(0.08
)
 
$
(0.27
)
 
$
(0.26
)
 
$
(0.19
)
 
$
(0.17
)
 
$
(0.12
)
Net increase (decrease) in net asset value  $0.35  $(0.66) $(0.03) $(0.04) $0.07  $(0.08)
Net asset value, end of period 
 
$
9.61
  
$
9.26
  
$
9.92
  
$
9.95
  
$
9.99
  
$
9.92
 
Total return (b)   4.67%(c)  (4.02)%  2.32%  1.51%  2.43%  0.41%
Ratio of net expenses to average net assets 
  
0.59
%(d)
  
0.58
%
  
0.59
%
  
0.60
%
  
0.61
%
  
0.63
%
Ratio of net investment income (loss) to average net assets 
  
1.39
%(d)
  
2.52
%
  
2.58
%
  
1.81
%
  
1.59
%
  
1.01
%
Portfolio turnover rate 
  
26
%(c)
  
100
%
  
61
%
  
54
%
  
69
%
  
58
%
Net assets, end of period (in thousands) 
 
$
1,635,493
  
$
1,628,082
  
$
1,506,433
  
$
1,209,820
  
$
759,455
  
$
673,352
 
 
*     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.
(c)   Not annualized.
(d)   Annualized.
The accompanying notes are an integral part of these financial statements.
96 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

                   
 
 Six Months                
 
 Ended  Year  Year  Year  Year  Year 
 
 9/30/20  Ended  Ended  Ended  Ended  Ended 
 
 (unaudited)  3/31/20  3/31/19  3/31/18  3/31/17*  3/31/16* 
Class C                  
Net asset value, beginning of period 
 
$
9.26
  
$
9.91
  
$
9.94
  
$
9.97
  
$
9.91
  
$
9.99
 
Increase (decrease) from investment operations: 
                        
Net investment income (loss) (a)  
$
0.05
  
$
0.22
  
$
0.22
  
$
0.15
  
$
0.13
  
$
0.07
 
Net realized and unrealized gain (loss) on investments   
0.38
   
(0.63
)
  
(0.02
)
  
(0.02
)
  
0.07
   
(0.06
)
Net increase (decrease) from investment operations  $0.43  $(0.41) $0.20  $0.13  $0.20  $0.01 
Distributions to shareowners: 
                        
Net investment income  
$
(0.07
)
 
$
(0.24
)
 
$
(0.23
)
 
$
(0.16
)
 
$
(0.14
)
 
$
(0.09
)
Net increase (decrease) in net asset value  $0.36  $(0.65) $(0.03) $(0.03) $0.06  $(0.08)
Net asset value, end of period 
 
$
9.62
  
$
9.26
  
$
9.91
  
$
9.94
  
$
9.97
  
$
9.91
 
Total return (b)   4.62%(c)  (4.24)%  1.99%  1.28%  2.00%  0.11%
Ratio of net expenses to average net assets 
  
0.90
%(d)
  
0.89
%
  
0.91
%
  
0.92
%
  
0.93
%
  
0.94
%
Ratio of net investment income (loss) to average net assets 
  
1.10
%(d)
  
2.25
%
  
2.22
%
  
1.48
%
  
1.27
%
  
0.70
%
Portfolio turnover rate 
  
26
%(c)
  
100
%
  
61
%
  
54
%
  
69
%
  
58
%
Net assets, end of period (in thousands) 
 
$
262,257
  
$
300,129
  
$
425,928
  
$
623,642
  
$
568,840
  
$
524,030
 
 
*     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.
(c)   Not annualized.
(d)   Annualized.
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 97
 

Financial Highlights (continued)
                   
 
 Six Months                
 
 Ended  Year  Year  Year  Year  Year 
 
 9/30/20  Ended  Ended  Ended  Ended  Ended 
 
 (unaudited)  3/31/20  3/31/19  3/31/18  3/31/17*  3/31/16* 
Class C2                   
Net asset value, beginning of period 
 
$
9.27
  
$
9.91
  
$
9.94
  
$
9.97
  
$
9.91
  
$
9.99
 
Increase (decrease) from investment operations: 
                        
Net investment income (loss) (a)  
$
0.05
  
$
0.21
  
$
0.22
  
$
0.15
  
$
0.13
  
$
0.07
 
Net realized and unrealized gain (loss) on investments   
0.37
   
(0.61
)
  
(0.02
)
  
(0.02
)
  
0.07
   
(0.06
)
Net increase (decrease) from investment operations  $0.42  $(0.40) $0.20  $0.13  $0.20  $0.01 
Distributions to shareowners: 
                        
Net investment income  
$
(0.07
)
 
$
(0.24
)
 
$
(0.23
)
 
$
(0.16
)
 
$
(0.14
)
 
$
(0.09
)
Net increase (decrease) in net asset value  $0.35  $(0.64) $(0.03) $(0.03) $0.06  $(0.08)
Net asset value, end of period 
 
$
9.62
  
$
9.27
  
$
9.91
  
$
9.94
  
$
9.97
  
$
9.91
 
Total return (b)   4.52%(c)  (4.13)%  1.98%  1.29%  2.00%  0.11%
Ratio of net expenses to average net assets 
  
0.92
%(d)
  
0.88
%
  
0.91
%
  
0.92
%
  
0.93
%
  
0.94
%
Ratio of net investment income (loss) to average net assets 
  
1.07
%(d)
  
2.17
%
  
2.25
%
  
1.47
%
  
1.27
%
  
0.69
%
Portfolio turnover rate 
  
26
%(c)
  
100
%
  
61
%
  
54
%
  
69
%
  
58
%
Net assets, end of period (in thousands) 
 
$
20,970
  
$
20,982
  
$
8,604
  
$
8,929
  
$
9,834
  
$
10,292
 
 
*     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.
(c)   Not annualized.
(d)   Annualized.
The accompanying notes are an integral part of these financial statements.
98 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

                   
 
 Six Months                
 
 Ended  Year  Year  Year  Year  Year 
 
 9/30/20  Ended  Ended  Ended  Ended  Ended 
 
 (unaudited)  3/31/20  3/31/19  3/31/18  3/31/17*  3/31/16* 
Class K                   
Net asset value, beginning of period 
 
$
9.29
  
$
9.93
  
$
9.96
  
$
9.99
  
$
9.93
  
$
10.01
 
Increase (decrease) from investment operations: 
                        
Net investment income (loss) (a)  
$
0.08
  
$
0.28
  
$
0.28
  
$
0.20
  
$
0.19
  
$
0.12
 
Net realized and unrealized gain (loss) on investments   
0.36
   
(0.62
)
  
(0.03
)
  
(0.02
)
  
0.06
   
(0.06
)
Net increase (decrease) from investment operations  $0.44  $(0.34) $0.25  $0.18  $0.25  $0.06 
Distributions to shareowners: 
                        
Net investment income  
$
(0.09
)
 
$
(0.30
)
 
$
(0.28
)
 
$
(0.21
)
 
$
(0.19
)
 
$
(0.14
)
Net increase (decrease) in net asset value  $0.35  $(0.64) $(0.03) $(0.03) $0.06  $(0.08)
Net asset value, end of period 
 
$
9.64
  
$
9.29
  
$
9.93
  
$
9.96
  
$
9.99
  
$
9.93
 
Total return (b)   4.78%(c)  (3.60)%  2.54%  1.83%  2.55%  0.64%
Ratio of net expenses to average net assets 
  
0.37
%(d)
  
0.36
%
  
0.37
%
  
0.38
%
  
0.42
%
  
0.42
%
Ratio of net investment income (loss) to average net assets 
  
1.62
%(d)
  
2.79
%
  
2.82
%
  
2.03
%
  
1.92
%
  
1.24
%
Portfolio turnover rate 
  
26
%(c)
  
100
%
  
61
%
  
54
%
  
69
%
  
58
%
Net assets, end of period (in thousands) 
 
$
265,749
  
$
264,405
  
$
274,682
  
$
158,443
  
$
91,666
  
$
5,026
 
 
*     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.
(c)   Not annualized.
(d)   Annualized.
The accompanying notes are an integral part of these financial statements.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 99
 

Financial Highlights (continued)
                   
 
 Six Months                
 
 Ended  Year  Year  Year  Year  Year 
 
 9/30/20  Ended  Ended  Ended  Ended  Ended 
 
 (unaudited)  3/31/20  3/31/19  3/31/18  3/31/17*  3/31/16* 
Class Y                   
Net asset value, beginning of period 
 
$
9.27
  
$
9.92
  
$
9.96
  
$
9.99
  
$
9.93
  
$
10.01
 
Increase (decrease) from investment operations: 
                        
Net investment income (loss) (a)  
$
0.07
  
$
0.27
  
$
0.27
  
$
0.19
  
$
0.17
  
$
0.11
 
Net realized and unrealized gain (loss) on investments   
0.38
   
(0.63
)
  
(0.04
)
  
(0.01
)
  
0.07
   
(0.06
)
Net increase (decrease) from investment operations  $0.45  $(0.36) $0.23  $0.18  $0.24  $0.05 
Distributions to shareowners: 
                        
Net investment income  
$
(0.09
)
 
$
(0.29
)
 
$
(0.27
)
 
$
(0.21
)
 
$
(0.18
)
 
$
(0.13
)
Net increase (decrease) in net asset value  $0.36  $(0.65) $(0.04) $(0.03) $0.06  $(0.08)
Net asset value, end of period 
 
$
9.63
  
$
9.27
  
$
9.92
  
$
9.96
  
$
9.99
  
$
9.93
 
Total return (b)   4.85%(c)  (3.78)%  2.37%  1.76%  2.46%  0.54%
Ratio of net expenses to average net assets 
  
0.44
%(d)
  
0.44
%
  
0.45
%
  
0.46
%
  
0.50
%
  
0.51
%
Ratio of net investment income (loss) to average net assets 
  
1.55
%(d)
  
2.69
%
  
2.74
%
  
1.94
%
  
1.70
%
  
1.15
%
Portfolio turnover rate 
  
26
%(c)
  
100
%
  
61
%
  
54
%
  
69
%
  
58
%
Net assets, end of period (in thousands) 
 
$
2,559,354
  
$
2,990,790
  
$
3,669,866
  
$
2,509,061
  
$
1,768,502
  
$
1,418,468
 
 
*     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.
(c)   Not annualized.
(d)   Annualized.
The accompanying notes are an integral part of these financial statements.
100 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

Notes to Financial Statements | 9/30/20
(unaudited)
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 Pioneer Asset Management, 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”). Amundi Pioneer Distributor, Inc., an affiliate of Amundi Pioneer Asset Management, Inc., serves as the Fund’s distributor (the “Distributor”).
During March 2017, the Financial Accounting Standards Board (FASB) issued an Accounting Standard Update, ASU 2017-08, Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities (“ASU 2017-08”), which shortens the amortization period for purchased non-contingently callable debt securities held at a premium. ASU 2017-08 specifies that the premium amortization period ends at the earliest call date, for certain purchased non-contingently callable debt securities. ASU 2017-08 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. The
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 101
 

Fund has adopted ASU 2017-08 as of January 1, 2019. The implementation of ASU 2017-08 did not have a material impact on the Fund’s financial statements.
The Fund is an investment company and follows investment company accounting and reporting guidance under 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. 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.
102 Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20
 

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.
Equity securities that have traded on an exchange are valued by using the last sale price on the principal exchange where they are traded. Equity securities that have not traded on the date of valuation, or securities for which sale prices are not available, generally are valued using the mean between the last bid and asked prices or, if both last bid and asked prices are not available, at the last quoted bid price. Last sale and bid and asked prices are provided by independent third party pricing services. In the case of equity securities not traded on an exchange, prices are typically determined by independent third party pricing services using a variety of techniques and methods.
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 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.
Pioneer Multi-Asset Ultrashort Income Fund | Semiannual Report | 9/30/20 103
 

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 September 30, 2020, 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
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.
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 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, 2020, 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.
The tax character of current year distributions payable will be determined at the end of the current taxable year. The tax character of distributions paid during the year ended March 31, 2020 was as follows:
    
 
 2020 
Distributions paid from:    
Ordinary income  
$
174,573,245
 
Total  $174,573,245 
 
The following shows the components of distributable earnings (losses) on a federal income tax basis at March 31, 2020:
    
 
 2020 
Distributable earnings:    
Undistributed ordinary income  
$
1,050,217
 
Capital loss carryforward   
(203,032,222
)
Current year dividend payable   
(1,141,032
)
Unrealized depreciation   
(283,923,963
)
Total  $(487,047,000)
 
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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 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 six months ended September 30, 2020.
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 4). 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 3).
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, 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 by the end of 2021. 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 broker-dealers, retirement platforms and other financial market participants over which neither the Fund nor Amundi 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 Amundi 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,
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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.
G.   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
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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.
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.
H.   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
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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 September 30, 2020, are disclosed 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 six months ended September 30, 2020, the effective management fee (excluding waivers and/or assumption of expenses) was equivalent to 0.31% (annualized) 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 $213,242 in management fees, administrative costs and certain other reimbursements payable to the Adviser at September 30, 2020.
3. 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 six months ended September 30, 2020, such out-of-pocket expenses by class of shares were as follows:
    
Shareowner Communications:    
Class A 
 
$
20,520
 
Class C 
  
5,262
 
Class C2 
  
21
 
Class K 
  
181
 
Class Y 
  
50,529
 
Total  $76,513 
 
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4. 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 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 $64,161 in distribution fees payable to the Distributor at September 30, 2020.
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 September 30, 2020, CDSCs in the amount of $9,472 were paid to the Distributor.
5. 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. 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 March 11, 2020, the Fund participates in a facility in the amount of $300 million. Prior to March 11, 2020, the Fund participated in a facility in the amount of $250 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 an annual commitment fee to participate in a credit facility. The commitment fee is allocated among participating Funds based on an allocation schedule set forth in the credit agreement. For the six months ended September 30, 2020, the Fund had no borrowings under the credit facility.
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6. 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.
As of September 30, 2020, the Fund had the following unfunded loan commitments outstanding:
     
 
 
 
 
Unrealized 
 
 
 
 
Appreciation/ 
Loan Principal Cost Value (Depreciation) 
NMN Holdings III Corp. 
$322,381 
$321,795 
$309,485 
$ (12,310) 
Total Value $322,381 $321,795 $309,485 $(12,310) 
 
7. Subsequent Event
On November 19, 2020, Amundi Pioneer Asset Management announced it will be rebranding the US business of Amundi as Amundi US effective January 1, 2021. The new brand identity will replace Amundi Pioneer, which was first adopted in July 2017 following the acquisition of Pioneer Investments by Amundi. In connection with these changes, Amundi Pioneer Asset Management. Inc., the investment adviser to the Pioneer funds, will change its name to Amundi Asset Management US, Inc. In addition, Amundi Pioneer Distributor, Inc., the Pioneer funds’ distributor, will change its name to Amundi Distributor US, Inc. The names of the Pioneer funds will not change in connection with this rebranding.
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Statement Regarding Liquidity Risk Management Program
As required by law, the Fund has adopted and implemented a liquidity risk management program (the “Program”) that is designed to assess and manage liquidity risk. Liquidity risk is the risk that the Fund could not meet requests to redeem its shares without significant dilution of remaining investors’ interests in the Fund. The Fund’s Board of Trustees designated a liquidity risk management committee (the “Committee”) consisting of employees of Amundi Pioneer Asset Management, Inc. (the “Adviser”) to administer the Program.
The Committee provided the Board of Trustees with a report that addressed the operation of the Program and assessed its adequacy and effectiveness of implementation (the “Report”). The Report covered the period from December 1, 2018 through March 31, 2020 (the “Reporting Period”).
The Report confirmed that, throughout the Reporting Period, the Committee had monitored the Fund’s portfolio liquidity and liquidity risk on an ongoing basis, as described in the Program and in Board reporting throughout the Reporting Period.
The Report discussed the Committee’s annual review of the Program, which addressed, among other things, the following elements of the Program:
The Committee reviewed the Fund’s investment strategy and liquidity of portfolio investments during both normal and reasonably foreseeable stressed conditions. The Committee noted that the Fund’s investment strategy continues to be appropriate for an open-end fund, taking into account, among other things, whether and to what extent the Fund held less liquid and illiquid assets and the extent to which any such investments affected the Fund’s ability to meet redemption requests. In managing and reviewing the Fund’s liquidity risk, the Committee also considered the extent to which the Fund’s investment strategy involves a relatively concentrated portfolio or large positions in particular issuers, the extent to which the Fund uses borrowing for investment purposes, and the extent to which the Fund uses derivatives (including for hedging purposes). The Committee also reviewed the Fund’s short-term and long-term cash flow projections during both normal and reasonably foreseeable stressed conditions. In assessing the Fund’s cash flow projections, the Committee considered, among other factors, historical net redemption activity, redemption policies, ownership concentration, distribution channels, and the degree of certainty associated with the Fund’s short-term and long-term cash flow projections. The Committee also considered the Fund’s
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holdings of cash and cash equivalents, as well as borrowing arrangements and other funding sources, including, if applicable, the Fund’s participation in a credit facility, as components of the Fund’s ability to meet redemption requests. The Fund has adopted an in-kind redemption policy which may be utilized to meet larger redemption requests.
The Committee reviewed the Program’s liquidity classification methodology for categorizing the Fund’s investments into one of four liquidity buckets. In reviewing the Fund’s investments, the Committee considered, among other factors, whether trading varying portions of a position in a particular portfolio investment or asset class in sizes the Fund would reasonably anticipate trading, would be reasonably expected to significantly affect liquidity.
The Committee performed an analysis to determine whether the Fund is required to maintain a Highly Liquid Investment Minimum, and determined that no such minimum is required because the Fund primarily holds highly liquid investments.
The Report stated that the Committee concluded the Program operates adequately and effectively, in all material respects, to assess and manage the Fund’s liquidity risk throughout the Reporting Period.
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Approval of Investment Management Agreement
Amundi Pioneer Asset Management, Inc. (“APAM”) serves as the investment adviser to Pioneer Multi-Asset Ultrashort Income Fund (the “Fund”) pursuant to an investment management agreement between APAM and the Fund. In order for APAM to remain the investment adviser of the Fund, the Trustees of the Fund must determine annually whether to renew the investment management agreement for the Fund.
The contract review process began in January 2020 as the Trustees of the Fund agreed on, among other things, an overall approach and timeline for the process. Contract review materials were provided to the Trustees in March 2020, July 2020 and September 2020. In addition, the Trustees reviewed and discussed the Fund’s performance at regularly scheduled meetings throughout the year, and took into account other information related to the Fund provided to the Trustees at regularly scheduled meetings, in connection with the review of the Fund’s investment management agreement.
In March 2020, the Trustees, among other things, discussed the memorandum provided by Fund counsel that summarized the legal standards and other considerations that are relevant to the Trustees in their deliberations regarding the renewal of the investment management agreement, and reviewed and discussed the qualifications of the investment management teams for the Fund, as well as the level of investment by the Fund’s portfolio managers in the Fund. In July 2020, the Trustees, among other things, reviewed the Fund’s management fees and total expense ratios, the financial statements of APAM and its parent companies, profitability analyses provided by APAM, and analyses from APAM as to possible economies of scale. The Trustees also reviewed the profitability of the institutional business of APAM and APAM’s affiliate, Amundi Pioneer Institutional Asset Management, Inc. (“APIAM” and, together with APAM, “Amundi”), as compared to that of APAM’s fund management business, and considered the differences between the fees and expenses of the Fund and the fees and expenses of APAM’s and APIAM’s institutional accounts, as well as the different services provided by APAM to the Fund and by APAM and APIAM to the institutional accounts. The Trustees further considered contract review materials, including additional materials received in response to the Trustees’ request, in September 2020.
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At a meeting held on September 15, 2020, based on their evaluation of the information provided by APAM and third parties, the Trustees of the Fund, including the Independent Trustees voting separately, unanimously approved the renewal of the investment management agreement for another year. In approving the renewal of the investment management agreement, the Trustees considered various factors that they determined were relevant, including the factors described below. The Trustees did not identify any single factor as the controlling factor in determining to approve the renewal of the agreement.
Nature, Extent and Quality of Services
The Trustees considered the nature, extent and quality of the services that had been provided by APAM to the Fund, taking into account the investment objective and strategy of the Fund. The Trustees also reviewed APAM’s investment approach for the Fund and its research process. The Trustees considered the resources of APAM and the personnel of APAM who provide investment management services to the Fund. They also reviewed the amount of non-Fund assets managed by the portfolio managers of the Fund. They considered the non-investment resources and personnel of APAM that are involved in APAM’s services to the Fund, including APAM’s compliance, risk management, and legal resources and personnel. The Trustees noted the substantial attention and high priority given by APAM’s senior management to the Pioneer Fund complex. The Trustees considered the implementation and effectiveness of APAM’s business continuity plan in response to the COVID-19 pandemic.
The Trustees considered that APAM supervises and monitors the performance of the Fund’s service providers and provides the Fund with personnel (including Fund officers) and other resources that are necessary for the Fund’s business management and operations. The Trustees also considered that, as administrator, APAM is responsible for the administration of the Fund’s business and other affairs. The Trustees considered the fees paid to APAM for the provision of administration services.
Based on these considerations, the Trustees concluded that the nature, extent and quality of services that had been provided by APAM to the Fund were satisfactory and consistent with the terms of the investment management agreement.
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Performance of the Fund
In considering the Fund’s performance, the Trustees regularly review and discuss throughout the year data prepared by APAM and information comparing the Fund’s performance with the performance of its peer group of funds, as classified by Morningstar, Inc. (Morningstar), and with the performance of the Fund’s benchmark index. They also discuss the Fund’s performance with APAM on a regular basis.
The Trustees discussed the Fund’s performance with the Adviser on a more frequent basis in light of the Fund’s unfavorable performance compared to its benchmark index and peers over certain periods. The Trustees noted APAM’s explanation for the Fund’s relative performance and the steps taken by APAM to address the Fund’s performance, including enhancing the investment process used for the Fund. The Trustees’ regular reviews and discussions were factored into the Trustees’ deliberations concerning the renewal of the investment management agreement.
Management Fee and Expenses
The Trustees considered information showing the fees and expenses of the Fund in comparison to the management fees of its peer group of funds as classified by Morningstar and also to the expense ratios of a peer group of funds selected on the basis of criteria determined by the Independent Trustees for this purpose using data provided by Strategic Insight Mutual Fund Research and Consulting, LLC (Strategic Insight), an independent third party. The peer group comparisons referred to below are organized in quintiles. Each quintile represents one-fifth of the peer group. In all peer group comparisons referred to below, first quintile is most favorable to the Fund’s shareowners. The Trustees noted that they separately review and consider the impact of the Fund’s transfer agency and Fund- and APAM-paid expenses for sub-transfer agency and intermediary arrangements, and that the results of the most recent such review were considered in the consideration of the Fund’s expense ratio.
The Trustees considered that the Fund’s management fee for the most recent fiscal year was in the third quintile relative to the management fees paid by other funds in its Morningstar category for the comparable period. The Trustees also considered the breakpoints in the management fee schedule and the reduced fee rates above certain asset levels. The Trustees considered that the expense ratio of the Fund’s Class A shares for the most recent fiscal year was in the second quintile relative to its Strategic Insight peer group for the comparable period. The Trustees considered that the expense ratio of the Fund’s Class Y shares for the most recent fiscal year was in the fourth quintile relative to its Strategic Insight peer group for the comparable period.
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The Trustees reviewed management fees charged by APAM and APIAM to institutional and other clients, including publicly offered European funds sponsored by APAM’s affiliates, unaffiliated U.S. registered investment companies (in a sub-advisory capacity), and unaffiliated foreign and domestic separate accounts. The Trustees also considered APAM’s costs in providing services to the Fund and APAM’s and APIAM’s costs in providing services to the other clients and considered the differences in management fees and profit margins for fund and non-fund services. In evaluating the fees associated with APAM’s and APIAM’s client accounts, the Trustees took into account the respective demands, resources and complexity associated with the Fund and other client accounts. The Trustees noted that, in some instances, the fee rates for those clients were lower than the management fee for the Fund and considered that, under the investment management agreement with the Fund, APAM performs additional services for the Fund that it does not provide to those other clients or services that are broader in scope, including oversight of the Fund’s other service providers and activities related to compliance and the extensive regulatory and tax regimes to which the Fund is subject. The Trustees also considered the entrepreneurial risks associated with APAM’s management of the Fund.
The Trustees concluded that the management fee payable by the Fund to APAM was reasonable in relation to the nature and quality of the services provided by APAM.
Profitability
The Trustees considered information provided by APAM regarding the profitability of APAM with respect to the advisory services provided by APAM to the Fund, including the methodology used by APAM in allocating certain of its costs to the management of the Fund. The Trustees also considered APAM’s profit margin in connection with the overall operation of the Fund. They further reviewed the financial results, including the profit margins, realized by APAM and APIAM from non-fund businesses. The Trustees considered APAM’s profit margins in comparison to the limited industry data available and noted that the profitability of any adviser was affected by numerous factors, including its organizational structure and method for allocating expenses. The Trustees concluded that APAM’s profitability with respect to the management of the Fund was not unreasonable.
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Economies of Scale
The Trustees considered APAM’s views relating to economies of scale in connection with the Pioneer Funds as fund assets grow and the extent to which any such economies of scale are shared with the Fund and Fund shareholders. The Trustees noted the breakpoints in the management fee schedule. The Trustees recognize that economies of scale are difficult to identify and quantify, and that, among other factors that may be relevant, are the following: fee levels, expense subsidization, investment by APAM in research and analytical capabilities and APAM’s commitment and resource allocation to the Fund. The Trustees noted that profitability also may be an indicator of the availability of any economies of scale, although profitability may vary for other reasons including due to reductions in expenses. The Trustees concluded that economies of scale, if any, were being appropriately shared with the Fund.
Other Benefits
The Trustees considered the other benefits that APAM enjoys from its relationship with the Fund. The Trustees considered the character and amount of fees paid or to be paid by the Fund, other than under the investment management agreement, for services provided by APAM and its affiliates. The Trustees further considered the revenues and profitability of APAM’s businesses other than the Fund business. To the extent applicable, the Trustees also considered the benefits to the Fund and to APAM and its affiliates from the use of “soft” commission dollars generated by the Fund to pay for research and brokerage services.
The Trustees considered that Amundi is the principal U.S. asset management business of Amundi, which is one of the largest asset managers globally. Amundi’s worldwide asset management business manages over $1.7 trillion in assets (including the Pioneer Funds). The Trustees considered that APAM’s relationship with Amundi creates potential opportunities for APAM, APIAM and Amundi that derive from APAM’s relationships with the Fund, including Amundi’s ability to market the services of APAM globally. The Trustees noted that APAM has access to additional research and portfolio management capabilities as a result of its relationship with Amundi and Amundi’s enhanced global presence that may contribute to an increase in the resources available to APAM. The Trustees considered that APAM and the Fund receive reciprocal intangible benefits from the relationship, including mutual brand recognition and, for the Fund, direct and indirect access to the resources of a large global asset manager. The Trustees concluded that any such benefits received by APAM as a result of its relationship with the Fund were reasonable.
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Conclusion
After consideration of the factors described above as well as other factors, the Trustees, including the Independent Trustees, concluded that the investment management agreement for the Fund, including the fees payable thereunder, was fair and reasonable and voted to approve the proposed renewal of the investment management agreement.
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Trustees, Officers and Service Providers
  
Trustees Officers 
Thomas J. Perna, Chairman 
Lisa M. Jones, President and 
John E. Baumgardner, Jr. 
Chief Executive Officer 
Diane Durnin 
Mark E. Bradley, Treasurer and 
Benjamin M. Friedman 
Chief Financial and 
Lisa M. Jones 
Accounting Officer 
Lorraine H. Monchak 
Christopher J. Kelley, Secretary and 
Marguerite A. Piret 
Chief Legal Officer 
Fred J. Ricciardi 
 
Kenneth J. Taubes 
 
 
Investment Adviser and Administrator
Amundi Pioneer Asset Management, Inc.

Custodian and Sub-Administrator
Brown Brothers Harriman & Co.

Principal Underwriter
Amundi Pioneer Distributor, 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.amundipioneer.com/us. This information is also available on the Securities and Exchange Commission’s web site at www.sec.gov.
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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.askamundipioneer@amundipioneer.com 
(for general questions about Amundi only) 
 
 
Visit our web site: www.amundipioneer.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 Pioneer Asset Management, Inc.
60 State Street
Boston, MA 02109
www.amundipioneer.com/us


Securities offered through Amundi Pioneer Funds Distributor, Inc.
60 State Street, Boston, MA 02109
Underwriter of Pioneer Mutual Funds, Member SIPC
© 2020 Amundi Pioneer Asset Management 25249-09-1120




Pioneer Fundamental Growth Fund
Semiannual Report | September 30, 2020
     
A: PIGFX C: FUNCX K: PFGKX R: PFGRX Y: FUNYX 
 
Beginning in or after March 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports like this one will no longer be 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 will be made 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.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications electronically by contacting your financial intermediary or, if you invest directly with the Fund, by calling 1-800-225-6292.
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.amundipioneer.com/us

 

  
Table of Contents 
 
  
  
  
  
  
  
  
  
  
  
  
  
 
Pioneer Fundamental Growth Fund | Semiannual Report | 9/30/20 1


President’s Letter


Dear Shareholders,
The new decade has arrived delivering a calendar year that will go down in the history books. The beginning of 2020 seemed to extend the positive market environment of 2019. Then, March roared in like a lion and the COVID-19 pandemic became a global crisis impacting lives and life as we know it. As the fourth quarter of 2020 got underway, it appeared that the long-anticipated “second wave” of COVID-19 cases was occurring, both in some U.S. states and in Europe. In response, some governments began retightening restrictions on both business and personal activities, likely assuring that the “new normal” conditions created by the pandemic will continue well into 2021.
The long-term impact on the global economy from the COVID-19 virus pandemic, 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, delivering significantly negative performance in the first quarter, and then recovering most of those losses throughout the rest of the spring and summer. Despite the rebound, volatility has remained elevated, with momentum rising and falling on seemingly every bit of positive or negative news regarding potential COVID-19 vaccines as well as headlines surrounding the U.S. elections.
Our business continuity plan was implemented given the new COVID-19 guidelines, and most of our employees are working remotely. 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.
Since 1928, Amundi’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 the first several months of 2020 have 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.
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At Amundi, 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 U.S.
Amundi Pioneer Asset Management USA, Inc.
September 30, 2020
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 | Semiannual Report | 9/30/20 3
 

Portfolio Management Discussion | 9/30/20
U.S. equity markets rebounded sharply during the six-month period ended September 30, 2020, as investors regained long-term confidence following the COVID-19 pandemic-driven bear market in February and March. In the following interview, Andrew Acheson and Paul Cloonan discuss the factors that affected the performance of Pioneer Fundamental Growth Fund during the six-month period. Mr. Acheson, Managing Director, Director of Growth, U.S., and a portfolio manager at Amundi Pioneer Asset Management, Inc. (Amundi*), and Mr. Cloonan, a senior vice president and a portfolio manager at Amundi, are responsible for the day-to-day management of the Fund.
Q How did the Fund perform during the six-month period ended September 30, 2020?
A Pioneer Fundamental Growth Fund’s Class A shares returned 37.41% at net asset value during the six-month period ended September 30, 2020, while the Fund’s benchmark, the Russell 1000 Growth Index (the Russell Index), returned 44.74%. During the same period, the average return of the 1,351 mutual funds in Morningstar’s Large Growth Funds category was 42.35%.
Q How would you describe the investment environment for domestic equity stocks during the six-month period ended September 30, 2020?
A The six-month period continued to feature elevated market volatility for U.S. equities. Unprecedented levels of monetary and fiscal stimulus from the Federal Reserve (Fed) and U.S. government boosted liquidity in the financial system and quickly generated a sense of optimism that the economic effects of the COVID-19 pandemic, though severe, could be short-lived. Corporate earnings results added to investors’ upbeat outlook, with second-quarter earnings surpassing consensus estimates by an unprecedented margin of more than 20%.
Markets continued to rally later in the period as many U.S. businesses reopened after the initial COVID-19-induced shutdowns aimed at slowing the spread of the virus. The economy showed several signs of strength, with a surge in consumer spending and housing sales. The Fed also signaled that interest rates would likely remain low for several years, lending support to equity valuations. In that environment, fixed-income alternatives offered little appeal to investors. However, after reaching
*  See Notes to Financial Statements Note 7.
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new highs in early September, markets became choppier as an uptick in COVID-19 case counts as well as uncertainty about the November presidential election combined to prompt a pullback.
Growth stocks outperformed value stocks by a wide margin during the six-month period, extending a streak of outperformance for the growth segment that has lasted for several years. Early in the six-month period, high-valuation growth stocks had the best returns, especially within the information technology sector. Later in the period, however, the consumer discretionary sector overtook information technology to become the Russell Index’s top-performing sector for the full six months.
Q What factors detracted from the Fund’s performance relative to the Russell Index benchmark during the six-month period ended September 30, 2020?
A During the six-month period, we maintained our traditional discipline of focusing the Fund’s investments on shares of higher-quality corporations with stable businesses and steady earnings. Given our focus on mitigating risk, the Fund’s performance has typically lagged that of the benchmark when markets have appreciated significantly, as was the case throughout most of the six-month period.
More specifically, three factors drove the Fund’s benchmark-relative underperformance. First, investors have largely been favoring high-growth, high-valuation stocks, and the returns of stocks with the highest price-to-earnings ratios represented in the benchmark have far exceeded the overall returns of the Russell Index. The Fund has been underweight in stocks of those companies, due to our concerns about the sustainability of their valuations.
Second, the unique nature of the COVID-19 economic contraction has hurt the performance of 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 in the past. However, store closures driven by COVID-19 restrictions have caused sales and profits for many of those businesses to decline sharply.
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 for us, especially as the concentration has also resulted in unprecedented exposure within the Russell Index to a single sector: information technology. In seeking to manage risk, we have deliberately maintained below-benchmark exposures in the Fund to those stocks, even as they have outperformed.
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Q Which individual stocks detracted from the Fund’s benchmark-relative performance during the six-month period ended September 30, 2020?
A The two biggest individual detractors from the Fund’s benchmark-relative returns during the six-month period were the portfolio’s lack of exposure to strong-performing electric vehicle manufacturer Tesla, and an underweight position in tech giant Apple, as share prices of both companies climbed sharply during the period. Tesla’s stock valuation has become excessive, in our view, and Apple’s weighting in the Russell Index had climbed to 11% or greater at times during the six-month period.
Specific portfolio holdings that notably detracted from the Fund’s benchmark-relative returns for the six-month period included off-price retailer Ross Stores. Many of the company’s stores had closed during much of the early part of the period due to COVID-19 restrictions. Ross Stores’ off-price business model has tended to make it a more defensive stock during recessions than stocks of full-price retailers, as consumers have typically become more price-conscious during difficult economic environments. Even as the company’s stores reopened later in the period, the share price continued to reflect health concerns among shoppers about visiting brick-and-mortar locations during the pandemic. We remain optimistic that Ross Stores’ customers will eventually become more comfortable with in-store shopping, and have retained the Fund’s position.
Another detractor from the Fund’s benchmark-relative returns during the six-month period was a position in insurance giant Progressive. Progressive’s profits have tended to be more resilient during economic downturns, as auto insurance coverage is mandatory in nearly all U.S. states. Moreover, auto accidents and resulting insurance claims have typically declined during times of rising unemployment as car owners drive fewer miles. However, as the economy reopened and driving behavior started returning to normal, or at least close to normal, investors’ sentiment toward Progressive declined, due to the anticipation of more auto accidents and a resulting increase in auto insurance claims payouts. We have retained the Fund’s position in Progressive, as we have continued to believe that the company’s long-term outlook remains positive, given its market share gains and profitability.
Finally, a position in Charles Schwab was a notable performance laggard for the Fund versus the benchmark during the six-month period. Continued downward pressure on interest rates has hurt the discount-brokerage firm, as Schwab has often generated much of its profits from
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lending activities. With interest rates at historically low levels, net interest margins have contracted. We believe the company’s competitive position has strengthened, however, and that its merger with TD Ameritrade (not a Fund holding), which closed after the end of the six-month period, may provide additional support. We have therefore retained the Fund’s position in Schwab.
Q Which investments contributed positively to the Fund’s benchmark-relative performance during the six-month period ended September 30, 2020?
A The largest individual positive contributor to the Fund’s performance relative to the Russell Index for the six-month period was a position in PayPal Holdings. PayPal’s large-scale technology platform for digital and mobile payments has benefited from a secular shift toward a cashless society, and the COVID-19 pandemic has accelerated the adoption of electronic payments by consumers across the globe. We believe that PayPal could continue to thrive as the economy recovers and consumers resume spending at higher levels. The company has featured high returns on capital and a wide “moat” around its business, with a network of nearly 350 million users and 26 million merchants.
Shares of tool-and-hardware manufacturer Stanley Black & Decker also made a strongly positive contribution to the Fund’s benchmark-relative performance during the six-month period. The home improvement industry has proved resilient during the pandemic, as those working from home have looked to make renovations to accommodate their changing needs. In response, home improvement retailers have overcome uncertainty about the broader economic conditions and restocked inventories, which has helped to boost Stanley Black & Decker’s revenues. In our opinion, the company’s strong brands, innovation, and global distribution capabilities have given it competitive advantages that could sustain its high returns on capital.
Finally, a position in cloud-software company salesforce.com was a notable positive contributor to the Fund’s relative returns during the six-month period. As one of the leading customer-relationship management platform providers globally, we believe the company could be in a strong position to benefit from secular growth in demand for its offerings. Salesforce’s scale, brand, and potentially increasing profitability have made it a good fit with our investment criteria for the Fund.
Pioneer Fundamental Growth Fund | Semiannual Report | 9/30/20 7
 

Q Did the Fund have any exposure to derivative securities during the six-month period ended September 30, 2020?
A No, the Fund had no exposure to derivatives during the six-month period.
Q What were some of the Fund’s most notable purchases during the six-month period ended September 30, 2020?
A We initiated a portfolio position in Colgate-Palmolive at what we believed was an attractive valuation during the six-month period. Colgate-Palmolive has had a strong, wide moat around its business, based on the company’s solid brands, global distribution capabilities, and scale-cost advantages. We believe that the company’s renewed focus on branding and innovation may lead to better growth trends, while potentially producing high returns on capital.
We also added shares of auto service provider Copart to the Fund during the period. Copart provides auction services to insurance companies related to the salvage of damaged vehicles. The company has consistently generated high returns on growth capital, driven by its scale and efficiency advantages. The increased complexity of automobiles has led to a rise in the number of accidents resulting in vehicles considered as “total losses.” That development has been a key factor in the growth of the number of cars sold through auction services providers.
Finally, late in the six-month period, we added Qualcomm, a designer of semiconductor chips for smartphones, to the portfolio. Qualcomm owns numerous patents for the technologies that make up the backbone of 3G, 4G, and coming 5G networks, and the company recently reported better-than-expected quarterly earnings results. We believe that Qualcomm’s intellectual property represents a large and sustainable competitive advantage that could result in profitable growth for the foreseeable future.
Q What were some of the noteworthy positions sold from the Fund’s portfolio during the six-month period ended September 30, 2020?
A During the six-month 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 (not a Fund holding). While incurred in conjunction with a strategic acquisition, we believe that the increased leverage levels have raised the company’s risk profile to a degree inconsistent with our focus on quality in managing the Fund’s investments. Moreover, the challenges presented by executing a major merger integration during a pandemic has created additional risks, and so we opted to sell the portfolio’s Elanco shares.
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Q What is your outlook heading into the second half of the Fund’s fiscal year, and how is the outlook reflected in the portfolio’s positioning?
A As we look ahead to the remainder of 2020 and into 2021, we expect that continued fiscal and monetary stimulus from the Fed and the U.S. government may be necessary to support the economy. Despite the fact that most U.S. economic indicators have shown improvement from the steep drop in activity caused by the COVID-19 pandemic during the first and second quarters of 2020, there has remained considerable uncertainty about the trajectory of the economy.
The potential approval of one or more COVID-19 vaccines could mark a key turning point for both the health crisis and the economy. Large-scale and successful deployment of vaccines, if and when that occurs, could spur accelerating economic growth, especially in the sectors hit hardest by the pandemic. In our view, such a broadening of performance leadership beyond higher-growth areas of the equity market could diminish the appeal of some stocks with what we see as exceptionally high valuations, particularly those that have benefited from the stay-at-home and shop-at-home trends brought about by the pandemic.
Conversely, a delay in developing effective vaccines for COVID-19 could create downside risk by leading to increased government restrictions on social and business activity in certain U.S. states. While hospitalization and mortality rates have fallen due to enhanced treatment protocols, another wave of COVID-19 cases could reverse the progress made thus far towards returning to pre-pandemic conditions.
The Fed appears intent on maintaining a highly accommodative monetary policy stance for the foreseeable future. Less certain is whether additional fiscal support will be forthcoming from the U.S. government. We are hopeful that the recent political impasse over fiscal stimulus can be resolved after the November election.
Regardless of the macroeconomic backdrop, we have remained committed to investing the Fund’s portfolio in shares of companies that we believe are highly profitable and that have strong balance sheets as well as sustainable business models. In managing the Fund, we seek to hold stocks of companies that we believe are capable of surviving a prolonged and deep recession and that may potentially emerge with the financial firepower to invest and thrive during the subsequent recovery.
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At the sector level, the Fund has remained overweight versus the benchmark in the financials sector, with a focus on holdings that have been less sensitive to narrowi