distributions into the next tax year and pay a 4% U.S. federal excise tax on such income. Any such carryover taxable income must be distributed through a dividend declared prior to filing the final tax return related to the year which generated such taxable income. For more information regarding tax treatment, see "Business — Regulation — Taxation as a Regulated Investment Company." Because we use debt financing, we are subject to certain asset coverage ratio requirements under the 1940 Act and are (and may in the future become) subject to certain financial covenants under loan and credit agreements that could, under certain circumstances, restrict us from making distributions necessary to satisfy the distribution requirement. In addition, because we receive non-cash sources of income such as PIK interest which involves us recognizing taxable income without receiving the cash representing

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such income, we may have difficulty meeting the distribution requirement. If we are unable to obtain cash from other sources, we could fail to qualify for RIC tax treatment and thus become subject to corporate-level U.S. federal income tax.

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The source-of-income requirement will be satisfied if we obtain at least 90% of our gross income for each year from distributions, interest, gains from the sale of stock or securities or similar sources.



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The asset diversification requirement will be satisfied if we meet certain asset diversification requirements at the end of each quarter of our taxable year. To satisfy this requirement, at least 50% of the value of our assets must consist of cash, cash equivalents, U.S. government securities, securities of other RICs, and other acceptable securities; and no more than 25% of the value of our assets can be invested in the securities, other than U.S. government securities or securities of other RICs, (i) of one issuer, (ii) of two or more issuers that are controlled, as determined under applicable Code rules, by us and that are engaged in the same or similar or related trades or businesses or (iii) of certain "qualified publicly traded partnerships."

       Failure to meet these requirements may result in our having to dispose of certain investments quickly in order to prevent the loss of RIC status. Because most of our investments will beare in privateprivately held companies, and therefore will be illiquid, any such dispositions could be made at disadvantageous prices and could result in substantial losses. Moreover, if we fail to maintain RIC tax treatment for any reason and are subject to corporate income tax, the resulting corporate taxes could substantially reduce our net assets, the amount of income available for distribution and the amount of our distributions.

We may not be able to pay distributions to our stockholders, our distributions may not grow over time, and a portion of distributions paid to our stockholders may be a return of capital, which is a distribution of the stockholders' invested capital.

       We intend to pay distributions to our stockholders out of assets legally available for distribution. We cannot assure you that we will achieve investment results that will allow us to pay a specified level of cash distributions, previously projected distributions for future periods, or year-to-year increases in cash distributions. Our ability to pay distributions might be adversely affected by, among other things, the impact of one or more of the risk factors described herein. In addition, the inability to satisfy the asset coverage test applicable to us as a BDC could limit our ability to pay distributions. All distributions will be paid at the discretion of our Board of Directors and will depend on our earnings, our financial condition, maintenance of our RIC status, compliance with applicable BDC regulations, compliance with our debt covenants, each of the Funds' compliance with applicable SBIC regulations and such other factors as our Board of Directors may deem relevant from time to time. We cannot assure you that we will pay distributions to our stockholders in the future.

       When we make distributions, we will be required to determine the extent to which such distributions are paid out of current or accumulated taxable earnings, recognized capital gains or capital. To the extent there is a return of capital, investors will be required to reduce their basis in our stock for U.S. federal income tax purposes, which may result in higher tax liability when the shares are sold, even if they have not increased in value or have lost value. In addition, any return of capital will be net of any sales load and offering expenses

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associated with sales of shares of our common stock. In the future, our distributions may include a return of capital.

We may have difficulty paying the distributions required to maintain RIC tax treatment under the Code if we recognize income before or without receiving cash representing such income.

       We will include in income certain amounts that we have not yet received in cash, such as: (i) amortization of original issue discount, which may arise if we receive warrants in connection with the origination of a loan such that ascribing a value to the warrants creates original issue discount in the debt instrument, if we invest in a debt investment at a discount to the par value of the debt security or possibly in other circumstances; (ii) contractual payment-in-kind, or PIK, interest, which represents contractual interest

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added to the loan balance and due at the end of the loan term; (iii) contractual preferred dividends, which represents contractual dividends added to the preferred stock and due at the end of the preferred stock term, subject to adequate profitability at the portfolio company; or (iv) amortization of market discount, which is associated with loans purchased in the secondary market at a discount to par value. Such amortization of original issue discounts, increases in loan balances as a result of contractual PIK arrangements, cumulative preferred dividends, or amortization of market discount will be included in income before we receive the corresponding cash payments. We also may be required to include in income certain other amounts before we receive such amounts in cash. Investments structured with these features may represent a higher level of credit risk compared to investments generating income which must be paid in cash on a current basis. For the year ended December 31, 2017,2018, (i) approximately 2.4%1.0% of our total investment income was attributable to PIK income not paid currently in cash, (ii) approximately 0.6%0.5% of our total investment income was attributable to amortization of original issue discount, (iii) approximately 1.6%1.0% of our total investment income was attributable to cumulative dividend income not paid currently in cash, and (iv) approximately 2.9%2.5% of our total investment income was attributable to amortization of market discount on loans purchased in the secondary market at a discount.

       Since, in certain cases, we may recognize taxable income before or without receiving cash representing such income, we may have difficulty meeting the Annual Distribution Requirement necessary to maintain RIC tax treatment under the Code. Accordingly, we may have to sell some of our investments at times and/or at prices we would not consider advantageous, raise additional debt or equity capital or forgo new investment opportunities for this purpose. If we are not able to obtain cash from other sources, we may fail to qualify for RIC tax treatment and thus become subject to corporate-level U.S. federal income tax. For additional discussion regarding the tax implications of a RIC, please see "Business — Regulation — Taxation as a Regulated Investment Company."

We may in the future choose to pay dividends in our own stock, in which case you may be required to pay tax in excess of the cash you receive.

       We may distribute taxable dividends that are payable in part in our stock. Under certain applicable provisions of the Code and the Treasury regulations, distributions payable by us in cash or in shares of stock (at the stockholders election) would satisfy the Annual Distribution Requirement. The Internal Revenue Service has issued guidance providing that a dividend payable in stock or in cash at the election of the stockholders will be treated as a taxable dividend eligible for the dividends paid deduction provided that at least 20% of the total dividend is payable in cash and certain other requirements are satisfied. Taxable stockholders receiving such dividends will be required to include the full amount of the dividend as ordinary income (or as long-term capital gain to the extent such dividend is properly reported as a capital gain dividend) to the extent of our current and accumulated earnings and profits for U.S. federal income tax purposes. As a result, a U.S. stockholder may be required to pay tax with respect to such dividends in excess of any cash received. If a U.S. stockholder sells the stock it receives as a dividend in order to pay this tax, the sales proceeds may be less than the amount included in income with respect to the dividend, depending on the market price of our stock at the time of the sale. Furthermore, with respect to non-U.S. stockholders, we may be required to withhold U.S. tax with respect to such dividends, including in respect of all or a portion of such dividend that is payable in stock. In addition, if a significant number of our stockholders determine to sell shares of our stock in order to pay taxes owed on dividends, it may put downward pressure on the trading price of our stock.

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Each of the Funds, as an SBIC, may be unable to make distributions to us that will enable us to meet or maintain RIC status, which could result in the imposition of an entity-level tax.

       In order for us to continue to qualify for RIC tax treatment and to minimize corporate-level U.S. federal taxes, we will be required to distribute substantially all of our net ordinary taxable income and net capital gain income, including taxable income from certain of our subsidiaries, which includes the income from the Funds. We will be partially dependent on the Funds for cash distributions to enable us to meet the RIC

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distribution requirements. The Funds may be limited by SBIC regulations from making certain distributions to us that may be necessary to enable us to maintain our status as a RIC. We may have to request a waiver of the SBA's restrictions for the Funds to make certain distributions to maintain our eligibility for RIC status. We cannot assure you that the SBA will grant such waiver and if the Funds are unable to obtain a waiver, compliance with the SBIC regulations may result in loss of RIC tax treatment and a consequent imposition of an entity-level tax on us.

Because we intend to distribute substantially all of our taxable income to our stockholders to maintain our status as a RIC, we will continue to need additional capital to finance our growth, and regulations governing our operation as a BDC will affect our ability to, and the way in which we, raise additional capital and make distributions.

       In order to satisfy the requirements applicable to a RIC and to minimize corporate-level U.S. federal taxes, we intend to distribute to our stockholders substantially all of our net ordinary taxable income and net capital gain income. We may carry forward excess undistributed taxable income into the next year, net of the 4% U.S. federal excise tax. Any such carryover taxable income must be distributed through a dividend declared prior to filing the final tax return related to the year which generated such taxable income. As a BDC, we generally are required to meet an asset coverage ratio, as defined in the 1940 Act, of at least 200% (or 150% if certain requirements are met) immediately after each issuance of senior securities. This requirement limits the amount that we may borrow and may prohibit us from making distributions. Because we will continue to need capital to grow our Investment Portfolio, this limitation may prevent us from incurring debt and require us to raise additional equity at a time when it may be disadvantageous to do so.

       While we expect to be able to borrow and to issue additional debt and equity securities, we cannot assure you that debt and equity financing will be available to us on favorable terms, or at all. In addition, as a BDC, we generally are not permitted to issue equity securities priced below net asset value without stockholder approval. If additional funds are not available to us, we could be forced to curtail or cease new investment activities, and our net asset value could decline.

Stockholders may incur dilution if we sell shares of our common stock in one or more offerings at prices below the then current net asset value per share of our common stock or issue securities to subscribe to, convert to or purchase shares of our common stock.

       The 1940 Act prohibits us from selling shares of our common stock at a price below the current net asset value per share of such stock, with certain exceptions. One such exception is prior stockholder approval of issuances below net asset value provided that our Board of Directors makes certain determinations. We did not seek stockholder authorization to sell shares of our common stock below the then current net asset value per share of our common stock at our 20172018 annual meeting of stockholders because our common stock price per share had been trading significantly above the net asset value per share of our common stock, and we do not currently expect to seek such approval at our 2018 annual meeting of stockholders for the same reason.stock. We may, however, seek such authorization at future annual or special meetings of stockholders. Our stockholders have previously approved a proposal to authorize us to issue securities to subscribe to, convert to, or purchase shares of our common stock in one or more offerings. Any decision to sell shares of our common stock below the then current net asset value per share of our common stock or securities to subscribe to, convert to, or purchase shares of our common stock would be subject to the determination by our Board of Directors that such issuance is in our and our stockholders' best interests.

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       If we were to sell shares of our common stock below net asset value per share, such sales would result in an immediate dilution to the net asset value per share. This dilution would occur as a result of the sale of shares at a price below the then current net asset value per share of our common stock and a proportionately greater decrease in a stockholder's interest in our earnings and assets and voting interest in us than the increase in our assets resulting from such issuance. In addition, if we issue securities to subscribe to, convert to or purchase shares of common stock, the exercise or conversion of such securities would increase the number of outstanding shares of our common stock. Any such exercise would be dilutive on the voting power

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of existing stockholders, and could be dilutive with regard to dividends and our net asset value, and other economic aspects of the common stock.

       Because the number of shares of common stock that could be so issued and the timing of any issuance is not currently known, the actual dilutive effect cannot be predicted; however, the example below illustrates the effect of dilution to existing stockholders resulting from the sale of common stock at prices below the net asset value of such shares.

       Illustration: Example of Dilutive Effect of the Issuance of Shares Below Net Asset Value.    Assume that Company XYZ has 1,000,000 total shares outstanding, $15,000,000 in total assets and $5,000,000 in total liabilities. The net asset value per share of the common stock of Company XYZ is $10.00. The following table illustrates the reduction to net asset value, or NAV, and the dilution experienced by Stockholder A following the sale of 40,000 shares of the common stock of Company XYZ at $9.50 per share, a price below its NAV per share.

Changes in laws or regulations governing our operations may adversely affect our business or cause us to alter our business strategy.

       We, the Funds, and our portfolio companies are subject to applicable local, state and federal laws and regulations. New legislation may be enacted or new interpretations, rulings or regulations could be adopted, including those governing the types of investments we are permitted to make, any of which could harm us and our stockholders, potentially with retroactive effect. In addition, any change to the SBA's current debenture SBIC program could have a significant impact on our ability to obtain lower-cost leverage through the Funds, and therefore, our ability to compete with other finance companies.

       Additionally, any changes to the laws and regulations governing our operations relating to permitted investments may cause us to alter our investment strategy in order to avail ourselves of new or different opportunities. Such changes could result in material differences to the strategies and plans set forth herein and may result in our investment focus shifting from the areas of expertise of our investment team to other types of investments in which our investment team may have less expertise or little or no experience. Thus, any such changes, if they occur, could have a material adverse effect on our results of operations and the value of your investment.

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The Tax Cuts and Jobs Act could have a negative effect on us, our subsidiaries, our portfolio companies and the holders of our Securities.securities.

       On December 20, 2017, the U.S. House of Representatives and the U.S. Senate each voted to approve H.R. 1 (the "Tax Cuts and Jobs Act") and, on December 22, 2017, President Trump signed the Tax Cuts and Jobs Act into law. The Tax Cuts and Jobs Act makesmade significant changes to the United StatesU.S. federal income tax rules applicable to both individuals and entities, including corporations. The Tax Cuts and Jobs Act includes provisions that, among other things, reduce the U.S. corporate tax rate, introduce a capital investment deduction, limit the interest deduction, limit the use of net operating losses to offset future taxable income

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and make extensive changes to the U.S. international tax system. TheTreasury and the Internal Revenue Service continue to release guidance in the form of regulations providing rules for implementation and interpretation of the Tax Cuts and Jobs Act is complexprovisions. Uncertainty remains regarding significant provisions of the Tax Cuts and far-reaching,Jobs Act while some of the Treasury regulations and guidance remain in proposed form. Accordingly, we cannot predict any additional future impact the impact its enactment of such legislation will have on us, our subsidiaries, our portfolio companies and the holders of our securities.

Terrorist attacks, acts of war or natural disasters may affect any market for our securities, impact the businesses in which we invest and harm our business, operating results and financial condition.

       Terrorist acts, acts of war or natural disasters may disrupt our operations, as well as the operations of the businesses in which we invest. Such acts have created, and continue to create, economic and political uncertainties and have contributed to global economic instability. Future terrorist activities, military or security operations, or natural disasters could further weaken the domestic/global economies and create additional uncertainties, which may negatively impact the businesses in which we invest directly or indirectly and, in turn, could have a material adverse impact on our business, operating results and financial condition. Losses from terrorist attacks and natural disasters are generally uninsurable.

We are highly dependent on information systems and systems failures could significantly disrupt our business, which may, in turn, negatively affect the market price of our common stock and our ability to pay dividends.

       Our business is highly dependent on our and third parties' communications and information systems. Any failure or interruption of those systems, including as a result of the termination of an agreement with any third-party service providers, could cause delays or other problems in our activities. Our financial, accounting, data processing, backup or other operating systems and facilities may fail to operate properly or become disabled or damaged as a result of a number of factors including events that are wholly or partially beyond our control and adversely affect our business. There could be:

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sudden electrical or telecommunications outages;



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natural disasters such as earthquakes, tornadoes and hurricanes;



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events arising from local or larger scale political or social matters, including terrorist acts; and



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cyber attacks.

The failure in cyber security systems, as well as the occurrence of events unanticipated in our disaster recovery systems and management continuity planning could impair our ability to conduct business effectively.

       The occurrence of a disaster such as a cyber-attack, a natural catastrophe, an industrial accident, a terrorist attack or war, events unanticipated in our disaster recovery systems, or a support failure from external providers, could have an adverse effect on our ability to conduct business and on our results of operations and financial condition, particularly if those events affect our computer-based data processing, transmission, storage, and retrieval systems or destroy data. If a significant number of our managers were unavailable in the event of a disaster, our ability to effectively conduct our business could be severely compromised.

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       We depend heavily upon computer systems to perform necessary business functions. Despite our implementation of a variety of security measures, our computer systems could be subject to cyber-attacks and unauthorized access, such as physical and electronic break-ins or unauthorized tampering. Like other companies, we may experience threats to our data and systems, including malware and computer virus attacks, unauthorized access, system failures and disruptions. If one or more of these events occurs, it could potentially jeopardize the confidential, proprietary and other information processed and stored in, and transmitted through, our computer systems and networks, or otherwise cause interruptions or malfunctions in

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our operations, which could result in damage to our reputation, financial losses, litigation, increased costs, regulatory penalties and/or customer dissatisfaction or loss.

RISKS RELATED TO OUR INVESTMENTS

Our investments in portfolio companies involve higher levels of risk, and we could lose all or part of our investment.

       Investing in our portfolio companies involvesexposes us indirectly to a number of significant risks. Among other things, these companies:

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may have limited financial resources and may be unable to meet their obligations under their debt instruments that we hold, which may be accompanied by a deterioration in the value of any collateral and a reduction in the likelihood of us realizing any guarantees from subsidiaries or affiliates of our portfolio companies that we may have obtained in connection with our investment, as well as a corresponding decrease in the value of the equity components of our investments;



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may have shorter operating histories, narrower product lines, smaller market shares and/or significant customer concentrations than larger businesses, which tend to render them more vulnerable to competitors' actions and market conditions, as well as general economic downturns;



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are more likely to depend on the management talents and efforts of a small group of persons; therefore, the death, disability, resignation, termination or significant under-performance of one or more of these persons could have a material adverse impact on our portfolio company and, in turn, on us;



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generally have less predictable operating results, may from time to time be parties to litigation, may be engaged in rapidly changing businesses with products subject to a substantial risk of obsolescence, and may require substantial additional capital to support their operations, finance expansion or maintain their competitive position; and



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generally have less publicly available information about their businesses, operations and financial condition. We are required to rely on the ability of our management team and investment professionals to obtain adequate information to evaluate the potential returns from investing in these companies. If we are unable to uncover all material information about these companies, we may not make a fully informed investment decision, and may lose all or part of our investment; and



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may utilize complex and speculative technologies such as blockchain and cryptocurrencies. These technologies have a limited history; rely on decentralized computer networks which could be affected by Internet connectivity disruptions, fraud or cybersecurity attacks; such networks may not be adequately maintained; future regulatory actions or policies may limit the use of effectiveness of such technologies; and the price of cryptocurrencies is volatile and may be impacted by the popularity, acceptance or use thereof.investment.

       In addition, in the course of providing significant managerial assistance to certain of our portfolio companies, certain of our officers and directors may serve as directors on the boards of such companies. To the extent that litigation arises out of our investments in these companies, our officers and directors may be named as defendants in such litigation, which could result in an expenditure of funds (through our indemnification of such officers and directors) and the diversion of management time and resources.

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A decline in oil and natural gas prices could have a material adverse effect on us.

       A decline in oil and natural gas prices could adversely affect (i) the credit quality of our debt investments and (ii) the underlying operating performance of our equity investments in energy-related businesses and in portfolio companies located in geographic areas which are more sensitive to the health of the oil and gas industries. A decrease in credit quality and the operating performance would, in turn, negatively affect the fair value of these investments, which would consequently negatively affect our net asset value. Should a decline in oil and natural gas prices persist for an extended period of time, it is likely that the ability of these investments to satisfy financial or operating covenants imposed by us or other lenders will be adversely affected, thereby negatively impacting their financial condition and their ability to satisfy their debt service and other obligations to us. Likewise, should a decline in oil and natural gas prices persist, it is likely that our energy-related portfolio companies' and other affected companies' cash flow and profit generating

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capacities would also be adversely affected thereby negatively impacting their ability to pay us dividends or distributions on our equity investments.

We may be exposed to higher risks with respect to our investments that include original issue discount or PIK interest.

       Our investments may include original issue discount and contractual PIK interest, which represents contractual interest added to a loan balance and due at the end of such loan's term. To the extent original issue discount or PIK interest constitute a portion of our income, we are exposed to typical risks associated with such income being required to be included in taxable and accounting income prior to receipt of cash, including the following:

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original issue discount and PIK instruments may have higher yields, which reflect the payment deferral and credit risk associated with these instruments;



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for accounting purposes, cash distributions to investors representing original issue discount and PIK accrualsincome are not derived from paid in capital, although they may create uncertainty aboutbe effectively paid from any offering proceeds during any given period; thus, although the source for the cash used to pay a distribution of our distributions to stockholders;original issue discount income may come from the cash invested by investors, the 1940 Act does not require that investors be given notice of this fact;



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original issue discount and PIK instruments may have unreliable valuations because their continuing accruals require continuing judgments about the collectability of the deferred payments and the value of the collateral; and



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original issue discount and PIK instruments may represent a higher credit risk than coupon loans.loans; even if the conditions for income accrual under generally accepted accounting principles in the United States of America are satisfied, a borrower could still default when actual payment is due upon the maturity of such loan.

The lack of liquidity in our investments may adversely affect our business.

       We invest in companies whose securities are not publicly traded, and whose securities will be subject to legal and other restrictions on resale or will otherwise be less liquid than publicly traded securities. The illiquidity of these investments may make it difficult for us to sell these investments when desired. In addition, if we are required to liquidate all or a portion of our portfolio quickly, we may realize significantly less than the value at which we had previously recorded these investments. As a result, we do not expect to achieve liquidity in our investments in the near-term. Our investments are usually subject to contractual or legal restrictions on resale or are otherwise illiquid because there is usually no established trading market for such investments. The illiquidity of most of our investments may make it difficult for us to dispose of them at a favorable price, and, as a result, we may suffer losses.

We may not have the funds or ability to make additional investments in our portfolio companies.

       We may not have the funds or ability to make additional investments in our portfolio companies. After our initial investment in a portfolio company, we may be called upon from time to time to provide additional funds to such company or have the opportunity to increase our investment through the extension of additional loans, the exercise of a warrant to purchase equity securities, or the funding of additional equity investments. There is no assurance that we will make, or will have sufficient funds to make, follow-on investments. Any decisions not to make a follow-on investment or any inability on our part to make such an investment may

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have a negative impact on a portfolio company in need of such an investment, may result in a missed opportunity for us to increase our participation in a successful operation, may reduce our ability to protect an existing investment or may reduce the expected yield on the investment.

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Our portfolio companies may incur debt that ranks equally with, or senior to, our investments in such companies.

       We invest primarily in the secured term debt of LMM, Private Loan and Middle Market companies and equity issued by LMM companies. Our portfolio companies may have, or may be permitted to incur, other debt that ranks equally with, or senior to, the debt in which we invest. By their terms, such debt instruments may entitle the holders to receive payment of interest or principal on or before the dates on which we are entitled to receive payments with respect to the debt instruments in which we invest. Also, in the event of insolvency, liquidation, dissolution, reorganization or bankruptcy of a portfolio company, holders of debt instruments ranking senior to our investment in that portfolio company would typically be entitled to receive payment in full before we receive any distribution. After repaying such senior creditors, such portfolio company may not have any remaining assets to use for repaying its obligation to us. In the case of debt ranking equally with debt instruments in which we invest, we would have to share on an equal basis any distributions with other creditors holding such debt in the event of an insolvency, liquidation, dissolution, reorganization or bankruptcy of the relevant portfolio company.

There may be circumstances where our debt investments could be subordinated to claims of other creditors or we could be subject to lender liability claims.

       Even though we may have structured certain of our investments as secured loans, if one of our portfolio companies were to go bankrupt, depending on the facts and circumstances, and based upon principles of equitable subordination as defined by existing case law, a bankruptcy court could subordinate all or a portion of our claim to that of other creditors and transfer any lien securing such subordinated claim to the bankruptcy estate. The principles of equitable subordination defined by case law have generally indicated that a claim may be subordinated only if its holder is guilty of misconduct or where the senior loan is re-characterized as an equity investment and the senior lender has actually provided significant managerial assistance to the bankrupt debtor. We may also be subject to lender liability claims for actions taken by us with respect to a borrower's business or instances where we exercise control over the borrower. It is possible that we could become subject to a lender liability claim, including as a result of actions taken in rendering significant managerial assistance or actions to compel and collect payments from the borrower outside the ordinary course of business.

Second priority liens on collateral securing loans that we make to our portfolio companies may be subject to control by senior creditors with first priority liens. If there is a default, the value of the collateral may not be sufficient to repay in full both the first priority creditors and us.

       Certain loans that we make are secured by a second priority security interest in the same collateral pledged by a portfolio company to secure senior debt owed by the portfolio company to commercial banks or other traditional lenders. Often the senior lender has procured covenants from the portfolio company prohibiting the incurrence of additional secured debt without the senior lender's consent. Prior to and as a condition of permitting the portfolio company to borrow money from us secured by the same collateral pledged to the senior lender, the senior lender will require assurances that it will control the disposition of any collateral in the event of bankruptcy or other default. In many such cases, the senior lender will require us to enter into an "intercreditor agreement" prior to permitting the portfolio company to borrow from us. Typically the intercreditor agreements we are requested to execute expressly subordinate our debt instruments to those held by the senior lender and further provide that the senior lender shall control: (1) the commencement of foreclosure or other proceedings to liquidate and collect on the collateral; (2) the nature, timing and conduct of foreclosure or other collection proceedings; (3) the amendment of any collateral document; (4) the release of the security interests in respect of any collateral; and (5) the waiver of defaults

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under any security agreement. Because of the control we may cede to senior lenders under intercreditor agreements we may enter, we may be unable to realize the proceeds of any collateral securing some of our loans.

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       Finally, the value of the collateral securing our debt investment will ultimately depend on market and economic conditions, the availability of buyers and other factors. Therefore, there can be no assurance that the proceeds, if any, from the sale or sales of all of the collateral would be sufficient to satisfy the loan obligations secured by our first or second priority liens. There is also a risk that such collateral securing our investments will decrease in value over time, will be difficult to sell in a timely manner, will be difficult to appraise and will fluctuate in value based upon the success of the portfolio company and market conditions. If such proceeds are not sufficient to repay amounts outstanding under the loan obligations secured by our second priority liens, then we, to the extent not repaid from the proceeds of the sale of the collateral, will only have an unsecured claim against the company's remaining assets, if any.

We are a non-diversified investment company within the meaning of the 1940 Act, and therefore we are not limited with respect to the proportion of our assets that may be invested in securities of a single issuer.

       We are classified as a non-diversified investment company within the meaning of the 1940 Act, which means that we are not limited by the 1940 Act with respect to the proportion of our assets that we may invest in securities of a single issuer. To the extent that we assume large positions in the securities of a small number of issuers, our net asset value may fluctuate to a greater extent than that of a diversified investment company as a result of changes in the financial condition or the market's assessment of the issuer. We may also be more susceptible to any single economic or regulatory occurrence than a diversified investment company. Beyond our RIC asset diversification requirements, we do not have fixed guidelines for diversification, and our investments could be concentrated in relatively few portfolio companies. See "Risk Factors — Risks RelatedRelating to Our Business and Structure — We will be subject to corporate-level U.S. federal income tax if we are unable to qualify as a RIC under Subchapter M of the Code."

We generally will not control our portfolio companies.

       We do not, and do not expect to, control the decision making in many of our portfolio companies, even though we may have board representation or board observation rights, and our debt agreements may contain certain restrictive covenants. As a result, we are subject to the risk that a portfolio company in which we invest will make business decisions with which we disagree and the management of such company will take risks or otherwise act in ways that do not serve our interests as debt investors or minority equity holders. Due to the lack of liquidity for our investments in non-traded companies, we may not be able to dispose of our interests in our portfolio companies as readily as we would like or at an appropriate valuation. As a result, a portfolio company may make decisions that would decrease the value of our portfolio holdings.

Defaults by our portfolio companies will harm our operating results.

       A portfolio company's failure to satisfy financial or operating covenants imposed by us or other lenders could lead to non-payment of interest and other defaults and, potentially, termination of its loans and foreclosure on its secured assets, which could trigger cross-defaults under other agreements and jeopardize a portfolio company's ability to meet its obligations under the debt or equity securities that we hold. We may incur expenses to the extent necessary to seek recovery upon default or to negotiate new terms, which may include the waiver of certain financial covenants, with a defaulting portfolio company.

Any unrealized depreciation we experience in our portfolio may be an indication of future realized losses, which could reduce our income and gains available for distribution.

       As a BDC, we are required to carry our investments at market value or, if no market value is ascertainable, at the fair value as determined in good faith by our Board of Directors. Decreases in the market

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values or fair values of our investments will be recorded as unrealized depreciation. Any unrealized depreciation in our portfolio could be an indication of a portfolio company's inability to meet its repayment obligations to us with respect to affected loans or a potential impairment of the value of affected equity investments. This could result in realized losses in the future and ultimately in reductions of our income and gains available for distribution in future periods.

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Prepayments of our debt investments by our portfolio companies could adversely impact our results of operations and reduce our return on equity.

       We are subject to the risk that the investments we make in our portfolio companies may be repaid prior to maturity. When this occurs, we will generally reinvest these proceeds in temporary investments, pending their future investment in new portfolio companies. These temporary investments will typically have substantially lower yields than the debt being prepaid and we could experience significant delays in reinvesting these amounts. Any future investment in a new portfolio company may also be at lower yields than the debt that was repaid. As a result, our results of operations could be materially adversely affected if one or more of our portfolio companies elect to prepay amounts owed to us. Additionally, prepayments could negatively impact our return on equity, which could result in a decline in the market price of our securities.

Changes in interest rates may affect our cost of capital, net investment income and value of our investments.

       Some of our debt investments will bear interest at variable rates and may be negatively affected by changes in market interest rates. An increase in market interest rates would increase the interest costs and reduce the cash flows of our portfolio companies that have variable rate debt instruments, a situation which could reduce the value of the investment. The value of our investments could also be reduced from an increase in market interest rates as rates available to investors could make an investment in our securities less attractive than alternative investments. In addition, an increase in interest rates would make it more expensive for us to use debt to finance our investments. As a result, a significant increase in market interest rates could increase our cost of capital, which would reduce our net investment income. Conversely, decreases in market interest rates could negatively impact the interest income from our variable rate debt investments. A decrease in market interest rates may also have an adverse impact on our returns by requiring us to accept lower yields on our debt investments and by increasing the risk that our portfolio companies will prepay our debt investments, resulting in the need to redeploy capital at potentially lower rates. See further discussion and analysis at "Item 7A. Quantitative and Qualitative Disclosures about Market Risk".

We may not realize gains from our equity investments.

       Certain investments that we have made in the past and may make in the future include warrants or other equity securities. Investments in equity securities involve a number of significant risks, including the risk of further dilution as a result of additional issuances, inability to access additional capital and failure to pay current distributions. Investments in preferred securities involve special risks, such as the risk of deferred distributions, credit risk, illiquidity and limited voting rights. In addition, we may from time to time make non-control, equity investments in portfolio companies. Our goal is ultimately to realize gains upon our disposition of such equity interests. However, the equity interests we receive may not appreciate in value and, in fact, may decline in value. Accordingly, we may not be able to realize gains from our equity interests, and any gains that we do realize on the disposition of any equity interests may not be sufficient to offset any other losses we experience. We also may be unable to realize any value if a portfolio company does not have a liquidity event, such as a sale of the business, recapitalization or public offering, which would allow us to sell the underlying equity interests. We often seek puts or similar rights to give us the right to sell our equity securities back to the portfolio company issuer; however, we may be unable to exercise these put rights for the consideration provided in our investment documents if the issuer is in financial distress.

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Our investments in foreign securities may involve significant risks in addition to the risks inherent in U.S. investments.

       Our investments in foreign securities may involve significant risks in addition to the risks inherent in investments in U.S. securities.       Our investment strategy contemplates potential investments in debt securities of foreign companies. Investing in foreign companies may expose us to additional risks not typically associated with investing in securities of U.S. companies. These risks include changes in exchange control regulations, political and social instability, expropriation, imposition of foreign taxes, less liquid markets and less available information than is generally the case in the U.S., higher transaction costs, less government supervision of exchanges, brokers and

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issuers, less developed bankruptcy laws, difficulty in enforcing contractual obligations, lack of uniform accounting and auditing standards and greater price volatility.

       Although most of our investments will be U.S. dollar denominated, any investments denominated in a foreign currency will be subject to the risk that the value of a particular currency will change in relation to one or more other currencies. Among the factors that may affect currency values are trade balances, the level of short-term interest rates, differences in relative values of similar assets in different currencies, long-term opportunities for investment and capital appreciation, and political developments.

RISKS RELATING TO OUR SECURITIES

Shares of closed-end investment companies, including BDCs, may trade at a discount to their net asset value.

       Shares of closed-end investment companies, including BDCs, may trade at a discount to net asset value. This characteristic of closed-end investment companies and BDCs is separate and distinct from the risk that our net asset value per share may decline. We cannot predict whether our common stock will trade at, above or below net asset value. In addition, if our common stock trades below our net asset value per share, we will generally not be able to issue additional common stock at the market price unless our stockholders approve such a sale and our Board of Directors makes certain determinations. See "—"Risk Factors — Risks Relating to Our Business and Structure — Stockholders may incur dilution if we sell shares of our common stock in one or more offerings at prices below the then current net asset value per share of our common stock or issue securities to subscribe to, convert to or purchase shares of our common stock" for a discussion related to us issuing shares of our common stock below net asset value.

We may be unable to invest a significant portion of the net proceeds from an offering or from exiting an investment or other capital on acceptable terms, which could harm our financial condition and operating results.

       Delays in investing the net proceeds raised in an offering or other capital raised or proceeds resulting from exiting an investment may cause our performance to be worse than that of other fully invested BDCs or other lenders or investors pursuing comparable investment strategies. We cannot assure you that we will be able to identify any investments that meet our investment objective or that any investment that we make will produce a positive return. We may be unable to invest the net proceeds of any offering or other capital raised or proceeds resulting from exiting an investment on acceptable terms within the time period that we anticipate or at all, which could harm our financial condition and operating results.

       We anticipate that, depending on market conditions and the amount of the capital, it may take us a substantial period of time to invest substantially all the capital in securities meeting our investment objective. During this period, we may invest the capital primarily in Marketablemarketable securities and idle funds investments, which generally consist of debt investments, independently rated debt investments, certificates of deposit with financial institutions, diversified bond funds and publicly traded debt and equity investments and may produce returns that are significantly lower than the returns which we expect to achieve when our portfolio is fully invested in securities meeting our investment objective. Most of the debt investments that meet our investment criteria are, or would be if rated, below investment grade quality. Indebtedness of below investment grade quality, which is often referred to as "junk," is regarded as having predominantly speculative characteristics with respect to the issuer's capacity to pay interest and repay principal. As a result, any distributions that we pay during such period may be substantially lower than the distributions that we may be able to pay when our portfolio is fully invested in securities meeting our investment objective. In addition, until such time as the net proceeds

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of any offering or from exiting an investment or other capital are invested in new securities meeting our investment objective, the market price for our securities may decline. Thus, the initial return on your investment may be lower than when, if ever, our portfolio is fully invested in securities meeting our investment objective.

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Investing in our securities may involve an above averagea high degree of risk.

       The investments we make in accordance with our investment objective may result in a higher amount of risk than alternative investment options and a higher risk of volatility or loss of principal. Our investments in portfolio companies involve higher levels of risk, and therefore, an investment in our securities may not be suitable for someone with lower risk tolerance.

The market price of our securities may be volatile and fluctuate significantly.

       Fluctuations in the trading prices of our securities may adversely affect the liquidity of the trading market for our securities and, if we seek to raise capital through future securities offerings, our ability to raise such capital. The market price and liquidity of the market for our securities may be significantly affected by numerous factors, some of which are beyond our control and may not be directly related to our operating performance. These factors include:

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significant volatility in the market price and trading volume of securities of BDCs or other companies in our sector, which are not necessarily related to the operating performance of these companies;



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changes in regulatory policies, accounting pronouncements or tax guidelines, particularly with respect to RICs, BDCs or SBICs;



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the exclusion of BDC common stock from certain market indices, such as what happened with respect to the Russell indices and the Standard and Poor's indices, could reduce the ability of certain investment funds to own our common stock and limit the number of owners of our common stock and otherwise negatively impact the market price of our common stock;



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inability to obtain any exemptive relief that may be required by us in the future from the SEC;



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loss of our BDC or RIC status or any of the Funds' status as an SBIC;



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changes in our earnings or variations in our operating results;



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changes in the value of our portfolio of investments;



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any shortfall in our investment income or net investment income or any increase in losses from levels expected by investors or securities analysts;



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loss of a major funding source;



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fluctuations in interest rates;



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the operating performance of companies comparable to us;



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departure of our key personnel;



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proposed, or completed, offerings of our securities, including classes other than our common stock;



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global or national credit market changes; and



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general economic trends and other external factors.

Provisions of the Maryland General Corporation Law and our articles of incorporation and bylaws could deter takeover attempts and have an adverse impact on the price of our common stock.

       The Maryland General Corporation Law and our articles of incorporation and bylaws contain provisions that may have the effect of discouraging, delaying or making difficult a change in control of our company or the removal of our incumbent directors. The existence of these provisions, among others, may have a negative

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impact on the price of our common stock and may discourage third-party bids for ownership of our company. These provisions may prevent any premiums being offered to you for our common stock.

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The Notes are unsecured and therefore effectively subordinated to any current or future secured indebtedness, including indebtedness under the Credit Facility.

       The Notes are not secured by any of our assets or any of the assets of our subsidiaries and rank equally in right of payment with all of our existing and future unsubordinated, unsecured indebtedness. As a result, the Notes are effectively subordinated to any secured indebtedness we or our subsidiaries have currently incurred and may incur in the future (or any indebtedness that is initially unsecured to which we subsequently grant security) to the extent of the value of the assets securing such indebtedness. In any liquidation, dissolution, bankruptcy or other similar proceeding, the holders of any of our existing or future secured indebtedness and the secured indebtedness of our subsidiaries may assert rights against the assets pledged to secure that indebtedness in order to receive full payment of their indebtedness before the assets may be used to pay other creditors, including the holders of the Notes. As of December 31, 2017,2018, we had $64.0$301.0 million outstanding under the Credit Facility out of $585.0$705.0 million in commitments. The indebtedness under the Credit Facility is senior to the Notes to the extent of the value of the assets securing such indebtedness.

The Notes are structurally subordinated to the indebtedness and other liabilities of our subsidiaries.

       The Notes are obligations exclusively of Main Street Capital Corporation and not of any of our subsidiaries. None of our subsidiaries is a guarantor of the Notes, and the Notes are not required to be guaranteed by any subsidiaries we may acquire or create in the future. In addition, several of our subsidiaries, specifically the Funds, maintain significant indebtedness and as a result the Notes are structurally subordinated to the indebtedness of these subsidiaries. For example, as of December 31, 2017,2018, the Funds had collectively issued $295.8$345.8 million of the current statutoryregulatory maximum of $350.0 million of SBA-guaranteed debentures, which are included in our consolidated financial statements. The assets of such subsidiaries are not directly available to satisfy the claims of our creditors, including holders of the Notes. See "Management's Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources" for more detail on the SBA-guaranteed debentures.

       Except to the extent we are a creditor with recognized claims against our subsidiaries, all claims of other creditors of our subsidiaries have priority over our equity interests in such subsidiaries (and therefore the claims of our creditors, including holders of the Notes) with respect to the assets of such subsidiaries. Even if we are recognized as a creditor of one or more of our subsidiaries, our claims would still be effectively subordinated to any security interests in the assets of any such subsidiary and to any indebtedness or other liabilities of any such subsidiary senior to our claims. Consequently, the Notes are structurally subordinated to all indebtedness, including the SBA-guaranteed debentures, and other liabilities of any of our subsidiaries and any subsidiaries that we may in the future acquire or establish. In addition, our subsidiaries may incur substantial additional indebtedness in the future, all of which would be structurally senior to the Notes.

The Notes may or may not have an established trading market. If a trading market in the Notes is developed, it may not be maintained.

       The Notes may or may not have an established trading market. If a trading market in the Notes is developed, it may not be maintained. If the Notes are traded, they may trade at a discount to their initial offering price depending on prevailing interest rates, the market for similar securities, our credit ratings, our financial condition or other relevant factors. Accordingly, we cannot assure you that a liquid trading market has been or will develop for the Notes, that you will be able to sell your Notes at a particular time or that the price you receive when you sell will be favorable. To the extent an active trading market does not develop or is not maintained, the liquidity and trading price for the Notes may be harmed. Accordingly, you may be required to bear the financial risk of an investment in the Notes for an indefinite period of time.

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A downgrade, suspension or withdrawal of the credit rating assigned by a rating agency to us or the Notes, if any, or change in the debt markets could cause the liquidity or market value of the Notes to decline significantly.

       Our credit ratings are an assessment by rating agencies of our ability to pay our debts when due. Consequently, real or anticipated changes in our credit ratings will generally affect the market value of the Notes. These credit ratings may not reflect the potential impact of risks relating to the structure or marketing of the Notes. Credit ratings are not a recommendation to buy, sell or hold any security, and may be revised or withdrawn at any time by the issuing organization in its sole discretion. We undertake no obligation to maintain our credit ratings or to advise holders of Notes of any changes in our credit ratings. The Notes are currently rated by Standard & Poor's Ratings Services. There can be no assurance that our credit ratings will remain for any given period of time or that such credit ratings will not be lowered or withdrawn entirely by the rating agency if in their judgment future circumstances relating to the basis of the credit ratings, such as adverse changes in our company, so warrant. The conditions of the financial markets and prevailing interest rates have fluctuated in the past and are likely to fluctuate in the future, which could have an adverse effect on the market prices of the Notes.

The indentures under which the Notes were issued contain limited protection for holders of the Notes.

       The indentures under which the Notes were issued offer limited protection to holders of the Notes. The terms of the indentures and the Notes do not restrict our or any of our subsidiaries' ability to engage in, or otherwise be a party to, a variety of corporate transactions, circumstances or events that could have an adverse impact on investments in the Notes. In particular, the terms of the indentures and the Notes do not place any restrictions on our or our subsidiaries' ability to:

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issue securities or otherwise incur additional indebtedness or other obligations, including (1) any indebtedness or other obligations that would be equal in right of payment to the Notes, (2) any indebtedness or other obligations that would be secured and therefore rank effectively senior in right of payment to the Notes to the extent of the values of the assets securing such debt, (3) indebtedness of ours that is guaranteed by one or more of our subsidiaries and which therefore is structurally senior to the Notes and (4) securities, indebtedness or obligations issued or incurred by our subsidiaries that would be senior to our equity interests in our subsidiaries and therefore rank structurally senior to the Notes with respect to the assets of our subsidiaries, in each case other than an incurrence of indebtedness or other obligation that would cause a violation of Section 18(a)(1)(A) as modified by Section 61(a)(1) of the 1940 Act or any successor provisions, but giving effect, in each case, to any exemptive relief granted to us by the SEC (currently, this provision generally prohibits us from making additional borrowings, including through the issuance of additional debt or the sale of additional debt securities, unless our asset coverage, as defined in the 1940 Act, equals at least 200% (or 150% if certain requirements are met) after such borrowings);



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pay dividends on, or purchase or redeem or make any payments in respect of, capital stock or other securities ranking junior in right of payment to the Notes, including subordinated indebtedness;



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sell assets (other than certain limited restrictions on our ability to consolidate, merge or sell all or substantially all of our assets);



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enter into transactions with affiliates;



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create liens (including liens on the shares of our subsidiaries) or enter into sale and leaseback transactions;



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make investments; or



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create restrictions on the payment of dividends or other amounts to us from our subsidiaries.

       Furthermore, the terms of the indentures and the Notes do not protect holders of the Notes in the event that we experience changes (including significant adverse changes) in our financial condition, results of

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operations or credit ratings, if any, as they do not require that we or our subsidiaries adhere to any financial tests or ratios or specified levels of net worth, revenues, income, cash flow or liquidity.

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       Our ability to recapitalize, incur additional debt and take a number of other actions that are not limited by the terms of the Notes may have important consequences for you as a holder of the Notes, including making it more difficult for us to satisfy our obligations with respect to the Notes or negatively affecting the trading value of the Notes.

       Other debt we issue or incur in the future could contain more protections for its holders than the indentures and the Notes, including additional covenants and events of default. For example, the indentures under which the Notes are issued do not contain cross-default provisions that are contained in the Credit Facility. The issuance or incurrence of any such debt with incremental protections could affect the market for and trading levels and prices of the Notes.

The optional redemption provision may materially adversely affect your return on the Notes.

       The 4.50% Notes are redeemable in whole or in part upon certain conditions at any time or from time to time at our option. The 6.125% Notes are redeemable in whole or in part upon certain conditions at any time or from time to time at our option, on or after April 1, 2018. We may choose to redeem the Notes at times when prevailing interest rates are lower than the interest rate paid on the Notes. In this circumstance, you may not be able to reinvest the redemption proceeds in a comparable security at an effective interest rate as high as the Notes being redeemed.

We may not be able to repurchase the 4.50% Notes upon a Change of Control Repurchase Event.

       We may not be able to repurchase the 4.50% Notes upon certain change in control events described in the indentures under which the 4.50% Notes were issued (each, a "Change of Control Repurchase Event") because we may not have sufficient funds. Upon a Change of Control Repurchase Event, holders of the 4.50% Notes may require us to repurchase for cash some or all of the 4.50% Notes at a repurchase price equal to 100% of the aggregate principal amount of the 4.50% Notes being repurchased, plus accrued and unpaid interest to, but not including, the repurchase date. The terms of our Credit Facility provide that certain change of control events will constitute an event of default thereunder entitling the lenders to accelerate any indebtedness outstanding under our Credit Facility at that time and to terminate the Credit Facility. In addition, the occurrence of a Change of Control Repurchase Event enabling the holders of the 4.50% Notes to require the mandatory purchase of the 4.50% Notes would constitute an event of default under our Credit Facility entitling the lenders to accelerate any indebtedness outstanding under our Credit Facility at that time and to terminate the Credit Facility. Our and our subsidiaries' future financing facilities may contain similar restrictions and provisions. Our failure to purchase such tendered 4.50% Notes upon the occurrence of such Change of Control Repurchase Event would cause an event of default under the indentures governing the 4.50% Notes and a cross-default under the agreements governing certain of our other indebtedness, which may result in the acceleration of such indebtedness requiring us to repay that indebtedness immediately. If a Change of Control Repurchase Event were to occur, we may not have sufficient funds to repay any such accelerated indebtedness.

If we default on our obligations to pay our other indebtedness, we may not be able to make payments on the Notes.

       As of December 31, 2017,2018, we had approximately $810.5$1,006.8 million of principal indebtedness, including $64.0$301.0 million outstanding under the Credit Facility, $295.8$345.8 million outstanding from SBA-guaranteed debentures, approximately $90.7 million of the 6.125% Notes, $175.0 million of the 4.50% Notes due 2019 and $185.0 million of the 4.50% Notes due 2022 outstanding. Any default under the agreements governing our indebtedness, including a default under the Credit Facility, under the Notes or under other indebtedness to which we may be a party that is not waived by the required lenders or debt holders, and the remedies sought by the holders of such indebtedness could make us unable to pay principal, premium, if any, and interest on

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the Notes and substantially decrease the market value of the Notes. If we are unable to generate sufficient cash flow and are otherwise unable to obtain funds necessary to meet required payments of principal, premium, if any, and interest on our indebtedness, or if we otherwise fail to comply with the various covenants, including financial and operating covenants, in the instruments governing our indebtedness, we could be in default under the terms of the agreements governing such indebtedness. In the event of such default, the holders of such indebtedness could elect to declare all the funds borrowed thereunder to be due and payable, together with accrued and unpaid interest, the lenders

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under the Credit Facility or other debt we may incur in the future could elect to terminate their commitments, cease making further loans and institute foreclosure proceedings against our assets, and we could be forced into bankruptcy or liquidation. Our ability to generate sufficient cash flow in the future is, to some extent, subject to general economic, financial, competitive, legislative and regulatory factors as well as other factors that are beyond our control. We cannot assure you that our business will generate cash flow from operations, or that future borrowings will be available to us under the Credit Facility or otherwise, in an amount sufficient to enable us to meet our payment obligations under the Notes and our other debt and to fund other liquidity needs.

       If our operating performance declines and we are not able to generate sufficient cash flow to service our debt obligations, we may in the future need to refinance or restructure our debt, including the Notes, sell assets, reduce or delay capital investments, seek to raise additional capital or seek to obtain waivers from the required lenders under the Credit Facility or the required holders of the Notes or other debt that we may incur in the future to avoid being in default. If we are unable to implement one or more of these alternatives, we may not be able to meet our payment obligations under the Notes and our other debt. If we breach our covenants under the Credit Facility, the Notes or other debt and seek a waiver, we may not be able to obtain a waiver from the required lenders or debt holders. If this occurs, we would be in default under the Credit Facility, the Notes or other debt, the lenders or debt holders could exercise their rights as described above, and we could be forced into bankruptcy or liquidation. If we are unable to repay debt, lenders having secured obligations could proceed against the collateral securing the debt. Because the Credit Facility has, and any future credit facilities will likely have, customary cross-default provisions, if the indebtedness under the Notes, the Credit Facility or under any future credit facility is accelerated, we may be unable to repay or finance the amounts due.

We may in the future determine to issue preferred stock, which could adversely affect the market value of our common stock.

       The issuance of shares of preferred stock with dividend or conversion rights, liquidation preferences or other economic terms favorable to the holders of preferred stock could adversely affect the market price for our common stock by making an investment in the common stock less attractive. In addition, the dividends on any preferred stock we issue must be cumulative. Payment of dividends and repayment of the liquidation preference of preferred stock must take preference over any dividends or other payments to our common stockholders, and holders of preferred stock are not subject to any of our expenses or losses and are not entitled to participate in any income or appreciation in excess of their stated preference (other than convertible preferred stock that converts into common stock). In addition, under the 1940 Act, preferred stock constitutes a "senior security" for purposes of the asset coverage test.

Item 1B.    Unresolved Staff Comments

       None.

Item 2.    Properties

       We do not own any real estate or other physical properties materially important to our operations. Currently, we lease office space in Houston, Texas for our corporate headquarters.

Item 3.    Legal Proceedings

       We may, from time to time, be involved in litigation arising out of our operations in the normal course of business or otherwise. Furthermore, third parties may seek to impose liability on us in connection with the activities of our portfolio companies. While the outcome of any current legal proceedings cannot at this time be predicted with certainty, we do not expect any current matters will materially affect our financial condition or results of operations; however, there can be no assurance whether any pending legal proceedings will have a material adverse effect on our financial condition or results of operations in any future reporting period.

Item 4.    Mine Safety Disclosures

       Not applicable.

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PART II

Item 5.    Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

PRICE RANGE OF COMMON STOCK, HOLDERS AND DISTRIBUTIONS

       Our common stock is traded on the New York Stock Exchange ("NYSE") under the symbol "MAIN." Prior to October 14, 2010, our common stock was traded on the NASDAQ Global Select Market under the same symbol "MAIN." Our common stock began trading on the NASDAQ Global Select Market on October 5, 2007. Prior to that date, there was no established public trading market for our common stock.

       The following table sets forth, for each fiscal quarter during 2017 and 2016, the range of high and low closing prices of our common stock as reported on the NYSE.

On February 22, 2018, the last sale price of our common stock on the NYSE was $35.70 per share, and27, 2019, there were approximately 312346 holders of record of the common stock which did not include stockholders for whom shares are held in "nominee" or "street name."

       Shares of BDCs may trade at a market price that is less than the value of the net assets attributable to those shares. The possibility that our shares of common stock will trade at a discount from net asset value per share or at premiums that are unsustainable over the long term are separate and distinct from the risk that our net asset value per share will decrease. It is not possible to predict whether our common stock will trade at, above, or below net asset value per share. Since our IPO in October 2007, our shares of common stock have traded at prices both less than and exceeding our net asset value per share.

       We currently pay regular monthly dividends and semiannual supplemental dividends to our stockholders. Our monthly dividends, if any, will be determined by our Board of Directors on a quarterly basis. Our semiannual supplemental dividends, if any, will also be determined by our Board of Directors based upon our undistributed taxable income.on a periodic basis. During 2018, we paid supplemental dividends of $0.275 per share in each of June and December 2018, regular monthly dividends of $0.190 per share for each month of January through September 2018, regular monthly dividends of $0.195 per share for each month of October through December 2018, with such dividends totaling $2.845 per share. The following table summarizes our2018 regular monthly dividends declared to date:

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       In accordance with the IRC sections 871(k) and 881(e), the following percentages represent the portion of our dividends that constitute interest-relatedinterest related dividends and short-term capital gains dividends for non-U.S. residents and foreign corporations.

Including the long-term capital gains discussed above, the following percentages represent the total dividends which are exempt from U.S. withholding tax.

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       To the extent non-U.S. resident taxes were withheld on ordinary dividends distributed, this information may be considered in connection with any claims for refund of such taxes to be filed by the non-U.S. resident stockholder with the Internal Revenue Service.

       To obtain and maintain RIC tax treatment, we must, among other things, distribute at least 90% of our net ordinary taxable income and realized net short-term capital gains in excess of realized net long-term capital losses, if any. We will be subject to a 4% non-deductible U.S. federal excise tax on certain undistributed taxable income unless we distribute in a timely manner an amount at least equal to the sum of (1) 98% of our net ordinary taxable income for each calendar year, (2) 98.2% of our capital gain net income for the one-year period ending December 31 in that calendar year and (3) any taxable income recognized, but not distributed, in preceding years on which we paid no U.S. federal income tax. Dividends declared and paid by us in a year will generally differ from taxable income for that year, as such dividends may include the distribution of current year taxable income, less amounts carried over into the following year, and the distribution of prior year taxable income carried over into and distributed in the current year. For amounts we carry over into the following year, we will be required to pay athe 4% U.S. federal excise tax on the amount by whichexcess of 98% of our annual ordinaryinvestment company taxable income and 98.2% of our capital gains exceedsgain net income over our distributions for

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the year. We may retain for investment some or all of our net capital gains (i.e., realized net long-term capital gains in excess of realized net short-term capital losses) and treat such amounts as deemed distributions to our stockholders. If we do this, our stockholders will be treated as if they had received actual distributions of the capital gains we retained and then reinvested the net after-tax proceeds in our common stock. In general, our stockholders also would be eligible to claim a tax credit (or, in certain circumstances, a tax refund) equal to their allocable shares of the tax we paid on the capital gains deemed distributed to them. We can offer no assurance that we will achieve results that will permit the payment of any cash distributions and, if we issue senior securities, we may be prohibited from making distributions if doing so causes us to fail to maintain the asset coverage ratios stipulated by the 1940 Act or if distributions are limited by the terms of any of our borrowings.

       We may distribute taxable dividends that are payable in part in our stock. Under certain applicable provisions of the Code and the Treasury regulations, distributions payable by us in cash or in shares of stock (at the stockholders election) would satisfy the Annual Distribution Requirement. The Internal Revenue Service has issued private letter rulingsguidance providing that a dividend payable in stock or in cash at the election of the stockholders will be treated as a taxable dividend eligible for the dividends paid deduction provided that at least 20% of the total dividend is payable in cash and certain other requirements are satisfied. Taxable stockholders receiving such dividends will be required to include the full amount of the dividend as ordinary income (or as long-term capital gain to the extent such dividend is properly reported as a capital gain dividend), to the extent of our current and accumulated earnings and profits for U.S. federal income tax purposes. As a result, a U.S. stockholder may be required to pay tax with respect to such dividends in excess of any cash received. If a U.S. stockholder sells the stock it receives as a dividend in order to pay this tax, the sales proceeds may be less than the amount included in income with respect to the dividend, depending on the market price of our stock at the time of the sale. Furthermore, with respect to non-U.S. stockholders, we may be required to withhold U.S. tax with respect to such dividends, including in respect of all or a portion of such dividend that is payable in stock. In addition, if a significant number of our stockholders determine to sell shares of our stock in order to pay taxes owed on dividends, it may put downward pressure on the trading price of our stock.

       We have adopted a dividend reinvestment plan ("DRIP") that provides for the reinvestment of dividends on behalf of our stockholders, unless a stockholder has elected to receive dividends in cash. As a result, if we declare a cash dividend, our stockholders who have not "opted out" of the DRIP by the dividend record date will have their cash dividend automatically reinvested into additional shares of MSCC common stock. The share requirements of the DRIP may be satisfied through the issuance of new shares of common stock or through open market purchases of common stock by the DRIP plan administrator. Newly issued shares will be valued based upon the final closing price of MSCC's common stock on a valuation date determined for each dividend by our Board of Directors. Shares purchased in the open market to satisfy the DRIP

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requirements will be valued based upon the average price of the applicable shares purchased by the DRIP plan administrator, before any associated brokerage or other costs. Our DRIP is administered by its transfer agent on behalf of our record holders and participating brokerage firms. Brokerage firms and other financial intermediaries may decide not to participate in our DRIP but may provide a similar dividend reinvestment plan for their clients.

SALES OF UNREGISTERED SECURITIES

       During the year ended December 31, 2017,2018, we issued a total of 234,513394,403 shares of our common stock under the DRIP. These issuances were not subject to the registration requirements of the Securities Act of 1933, as amended. The aggregate value of the shares of our common stock issued under the DRIP during 20172018 was approximately $9.2$14.9 million.

PURCHASES OF EQUITY SECURITIES

       None.

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STOCK PERFORMANCE GRAPH

       The following graph compares the stockholder return on our common stock from October 5, 2007 to December 31, 20172018 with the S&P 500 Index, the Russell 2000 Index, the KBW Regional Bank Index and the Main Street Peer Group (as defined below). This comparison assumes $100.00 was invested on October 5, 2007 (the date our common stock began to trade in connection with our initial public offering) in our common stock and in the comparison groups and assumes the reinvestment of all cash dividends prior to any tax effect. The comparisons in the graph below are based on historical data and are not intended to forecast the possible future performance of our common stock.

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COMPARISON OF STOCKHOLDER RETURN(1)
Among Main Street Capital Corporation, the S&P 500 Index, the Russell 2000 Index, the KBW
Regional Bank Index, and the Main Street Peer Group(2)
(For the Period October 5, 2007 to December 31, 2017)2018)

TOTAL RETURN PERFORMANCE SINCE IPO

(1)

Total return includes reinvestment of dividends through December 31, 2017.2018.

(2)

The Main Street Peer Group is composed of Apollo Investment Corporation, Ares Capital Corporation, BlackRock Capital Investment Corporation, Blackrock TCP Capital Corp., Capitala Finance Corp., Fidus Investment Corporation, FS KKR Capital Corp., Gladstone Investment Corporation, Goldman Sachs BDC, Inc., Golub Capital BDC, Inc., Hercules Capital, Inc., Medallion Financial Corp., Medley Capital Corporation, Monroe Capital Corporation, New Mountain Finance Corporation, Newtek Business Services Corp., Oaktree Specialty Lending Corporation, Oaktree Strategic Income Corporation, PennantPark Floating Rate Capital Ltd., PennantPark Investment Corporation, Prospect Capital Corporation, Solar Capital Ltd., Solar Senior Capital Ltd., TCP Capital Corp., THL Credit, Inc., TICC Capital Corp., TPG Specialty Lending, Inc. and Triangle Capital Corporation.TriplePoint Venture Growth BDC Corp.

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Item 6.    Selected Financial Data

       The selected financial and other data as of and for the years ended December 31, 2018, 2017, 2016, 2015 2014 and 20132014 have been derived from consolidated financial statements that have been audited by Grant Thornton LLP, an independent registered public accounting firm. You should read this selected financial and other data in conjunction with our "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the consolidated financial statements and related notes included in this Annual Report on Form 10-K.

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