In addition to regulatory requirements that restrict our ability to raise capital, the Facilities, the Unsecured Notes and the Convertible Notes contain various covenants that, if not complied with, could accelerate repayment under the Facilities, the Unsecured Notes and the Convertible Notes, thereby materially and adversely affecting our liquidity, financial condition and results of operations.

        The agreements governing the Facilities, the Unsecured Notes and the Convertible Notes require us to comply with certain financial and operational covenants. These covenants include:

•

restrictions on the level of indebtedness that we are permitted to incur in relation to the value of our assets;



•

restrictions on our ability to incur liens; and



•

maintenance of a minimum level of stockholders' equity.

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        As of the date of this prospectus, we are in compliance in all material respects with the covenants of the Facilities, the Unsecured Notes and the Convertible Notes. However, our continued compliance with these covenants depends on many factors, some of which are beyond our control. For example, depending on the condition of the public debt and equity markets and pricing levels, net unrealized depreciation in our portfolio may increase in the future. Any such increase could result in our inability to comply with our obligation to restrict the level of indebtedness that we are able to incur in relation to the value of our assets or to maintain a minimum level of stockholders' equity.

        Accordingly, although we believe we will continue to be in compliance, there are no assurances that we will continue to comply with the covenants in the Facilities, the Unsecured Notes and the Convertible Notes. Failure to comply with these covenants could result in a default under the Facilities, the Unsecured Notes or the Convertible Notes that, if we were unable to obtain a waiver from the lenders or holders of such indebtedness, as applicable, such lenders or holders could accelerate repayment under such indebtedness and thereby have a material adverse impact on our business, financial condition and results of operations.

Our credit ratings may change and as a result the cost and flexibility under our debt instruments may change.

        As of March 31, 2012, we had a long-term counterparty credit rating from Standard & Poor's Ratings Services of "BBB," a long-term issuer default rating from Fitch Ratings of "BBB" and a long-term issuer rating from Moody's Investors Service of "Ba1." Interest expense on our Revolving Credit Facility is based on a pricing grid that fluctuates depending on our credit ratings. There can be no assurance that our ratings will be maintained. If our ratings are downgraded, our cost of borrowing will increase.

        In addition, ratings agencies are required to make substantial changes to their ratings policies and practices as a result of the Dodd-Frank Wall Street Reform and Consumer Protection Act (the "Dodd-Frank Act"), which President Obama signed into law on July 21, 2010. There can be no assurance that such changes will not affect our ratings.

We operate in a highly competitive market for investment opportunities.

        A number of entities compete with us to make the types of investments that we make in middle-market companies. We compete with other BDCs, public and private funds, commercial and investment banks, commercial financing companies, insurance companies, hedge funds, and, to the extent they provide an alternative form of financing, private equity funds. Many of our competitors are substantially larger and have considerably greater financial, technical and marketing resources than we do. Some competitors may have a lower cost of funds and access to funding sources that are not available to us. In addition, some of our competitors may have higher risk tolerances or different risk assessments, which could allow them to consider a wider variety of investments and establish more relationships than us. Furthermore, many of our competitors are not subject to the regulatory restrictions that the Investment Company Act imposes on us as a BDC and that the Code imposes on us as a RIC. We cannot assure you that the competitive pressures we face will not have a material adverse effect on our business, financial condition and results of operations. Also, as a result of this competition, we may not be able to pursue attractive investment opportunities from time to time.

        We do not seek to compete primarily based on the interest rates we offer and we believe that some of our competitors may make loans with interest rates that are comparable to or lower than the rates we offer. Rather, we compete with our competitors based on our existing investment platform, seasoned investment professionals, experience and focus on middle-market companies, disciplined investment philosophy, extensive industry focus and flexible transaction structuring. For a more detailed discussion of these competitive advantages, see "Business—Competitive Advantages."

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        We may lose investment opportunities if we do not match our competitors' pricing, terms and structure. If we match our competitors' pricing, terms and structure, we may experience decreased net interest income and increased risk of credit loss. As a result of operating in such a competitive environment, we may make investments that are on less favorable terms than what we may have originally anticipated, which may impact our return on these investments.

We may be subject to certain corporate-level taxes regardless of whether we continue to qualify as a RIC.

        We have elected to be treated as a RIC under Subchapter M of the Code and operate in a manner so as to qualify for the U.S. federal income tax treatment applicable to RICs. As a RIC, we generally will not pay corporate-level U.S. federal income taxes on our income and gain that we distribute to our stockholders as dividends on a timely basis. We will be subject to corporate-level U.S. federal income tax on any undistributed income and/or gain. To qualify as a RIC, we must meet certain source of income, asset diversification and annual distribution requirements. We may also be subject to certain U.S. federal excise taxes, as well as state, local and foreign taxes.

        To satisfy the Annual Distribution Requirement (as defined below) for a RIC we must distribute to our stockholders on a timely basis generally an amount equal to at least 90% of our investment company taxable income for each year. We have the ability to pay a large portion of our dividends in shares of our stock, and as long as a portion of such dividend is paid in cash and other requirements are met, such stock dividends will be taxable as a dividend for U.S. federal income tax purposes. This may result in our U.S. stockholders having to pay tax on such dividends, even if no cash is received, and may result in our non-U.S. stockholders being subject to withholding tax in respect of amounts distributed in our stock. Because we use debt financing, we are subject to certain asset coverage ratio requirements under the Investment Company Act and financial covenants under our indebtedness that could, under certain circumstances, restrict us from making distributions necessary to qualify as a RIC. If we are unable to obtain cash from other sources, we may fail to qualify as a RIC and, thus, may be subject to corporate- level income tax on all of our income and/or gain.

        To qualify as a RIC, we must also meet certain annual source of income requirements at the end of each taxable year and asset diversification requirements at the end of each calendar quarter. Failure to meet these tests may result in our having to (a) dispose of certain investments quickly or (b) raise additional capital to prevent the loss of RIC status. Because most of our investments are in private companies and are generally illiquid, any such dispositions may be at disadvantageous prices and may result in losses. Also, the rules applicable to our qualification as a RIC are complex with many areas of uncertainty. Accordingly, no assurance can be given that we have qualified or will continue to qualify as a RIC. If we fail to qualify as a RIC for any reason and become subject to regular "C" corporation 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. Such a failure would have a material adverse effect on us and our stockholders. The recently enacted "Regulated Investment Company Modernization Act of 2010," which is effective for 2011 and later tax years, provides some relief from RIC disqualification due to failures of the source of income and asset diversification requirements, although there may be additional taxes due in such cases. We cannot assure you that we would qualify for any such relief should we fail the source of income or asset diversification requirements.

We may have difficulty paying our required distributions under applicable tax rules if we recognize income before or without receiving cash representing such income.

        For U.S. federal income tax purposes, we are required to include in income certain amounts that we have not yet received in cash, such as original issue discount, which may arise, for example, if we receive warrants in connection with the making of a loan, or payment-in-kind ("PIK") interest

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representing contractual interest added to the loan principal balance and due at the end of the loan term. Such original issue discount or PIK interest are included in income before we receive any corresponding cash payments. We also may be required to include in income certain other amounts that we will not receive in cash, including, for example, amounts attributable to hedging and foreign currency transactions or cancellation of indebtedness income resulting from a restructuring of an investment in debt securities.

        Since, in certain cases, we may recognize income before or without receiving cash in respect of such income, we may have difficulty meeting the U.S. federal income tax requirement to distribute generally an amount equal to at least 90% of our investment company taxable income to maintain our status as a RIC. Accordingly, we may have to sell some of our investments at times we would not consider advantageous, raise additional debt or equity capital or reduce new investment originations to meet these distribution requirements. If we are not able to obtain cash from other sources, we may fail to qualify as a RIC and thus be subject to additional corporate-level taxes. Such a failure would have a material adverse effect on us and on our stockholders. See "Certain Material U.S. Federal Income Tax Considerations—Taxation as a RIC."

We are exposed to risks associated with changes in interest rates.

        General interest rate fluctuations may have a substantial negative impact on our investments and investment opportunities and, accordingly, may have a material adverse effect on our investment objective and rate of return on invested capital. Because we borrow money and may issue debt securities or preferred stock to make investments, our net investment income is dependent upon the difference between the rate at which we borrow funds or pay interest or dividends on such debt securities or preferred stock and the rate at which we invest these funds. As a result, there can be no assurance that a significant change in market interest rates will not have a material adverse effect on our net investment income.

        Trading prices for debt that pays a fixed rate of return tend to fall as interest rates rise. Trading prices tend to fluctuate more for fixed-rate securities that have longer maturities. In the past, we have entered into certain hedging transactions, such as interest rate swap agreements, to mitigate our exposure to adverse fluctuations in interest rates, and we may do so again in the future. In addition, we may increase our floating rate investments to position the portfolio for rate increases. However, we cannot assure you that such transactions will be successful in mitigating our exposure to interest rate risk. Hedging transactions may also limit our ability to participate in the benefits of lower interest rates with respect to our portfolio investments.

        Although we have no policy governing the maturities of our investments, under current market conditions we expect that we will invest in a portfolio of debt generally having maturities of up to 10 years. This means that we are subject to greater risk (other things being equal) than a fund invested solely in shorter-term securities. A decline in the prices of the debt we own could adversely affect the trading price of our shares. Also, an increase in interest rates available to investors could make an investment in our common stock less attractive if we are not able to increase our dividend rate, which could reduce the value of our common stock.

Most of our portfolio investments are not publicly traded and, as a result, the fair value of these investments may not be readily determinable.

        A large percentage of our portfolio investments are not publicly traded. The fair value of investments that are not publicly traded may not be readily determinable. We value these investments quarterly at fair value as determined in good faith by our board of directors based on, among other things, the input of our management and audit committee and independent valuation firms that have been engaged at the direction of our board of directors to assist in the valuation of each portfolio

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investment without a readily available market quotation at least once during a trailing 12-month period (with certain de minimis exceptions). The valuation process is conducted at the end of each fiscal quarter, with a minimum of 50% (based on value) of our valuations of portfolio companies without readily available market quotations subject to review by an independent valuation firm each quarter. However, we may use additional independent valuation firms to review the value of our investments more frequently, including in connection with the occurrence of significant events or changes in value affecting a particular investment. In addition, our independent accountants review our valuation process as part of their overall integrated audit. The types of factors that may be considered in valuing our investments include the enterprise value of the portfolio company (the entire value of the portfolio company to a market participant, including the sum of the values of debt and equity securities used to capitalize the enterprise at a point in time), the nature and realizable value of any collateral, the portfolio company's ability to make payments and its earnings and discounted cash flows, the markets in which the portfolio company does business, a comparison of the portfolio company's securities to similar publicly traded companies, changes in the interest rate environment and the credit markets generally that may affect the price at which similar investments would trade in their principal markets and other relevant factors. When an external event such as a purchase transaction, public offering or subsequent equity sale occurs, we consider the pricing indicated by the external event to corroborate our valuation. Because such valuations, and particularly valuations of private investments and private companies are inherently uncertain, may fluctuate over short periods of time and may be based on estimates, our determinations of fair value may differ materially from the values that would have been used if a ready market for these investments existed and may differ materially from the values that we may ultimately realize. Our net asset value per share could be adversely affected if our determinations regarding the fair value of these investments are materially higher than the values that we realize upon disposition of such investments.

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

        As we generally make investments in private companies, substantially all of these investments are subject to legal and other restrictions on resale or are otherwise less liquid than publicly traded securities. The illiquidity of our investments may make it difficult for us to sell such investments if the need arises. In addition, if we are required to liquidate all or a portion of our portfolio quickly, we could realize significantly less than the value at which we have recorded our investments. In addition, we may face other restrictions on our ability to liquidate an investment in a portfolio company to the extent that we or an affiliated manager of Ares has material non-public information regarding such portfolio company.

We may experience fluctuations in our quarterly results.

        We could experience fluctuations in our quarterly operating results due to a number of factors, including the interest rates payable on the debt investments we make, the default rates on such investments, the level of our expenses, variations in and the timing of the recognition of realized and unrealized gains or losses, the degree to which we encounter competition in our markets and general economic conditions. As a result of these factors, results for any period should not be relied upon as being indicative of performance in future periods.

There are significant potential conflicts of interest that could impact our investment returns.

        Certain of our executive officers and directors, and members of the investment committee of our investment adviser, serve or may serve as officers, directors or principals of other entities and affiliates of our investment adviser and investment funds managed by our affiliates. Accordingly, they may have obligations to investors in those entities, the fulfillment of which might not be in our or our stockholders' best interests or that may require them to devote time to services for other entities, which

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could interfere with the time available to provide services to us. Certain members of our investment adviser's investment committee have significant responsibilities for other Ares funds. For example, Messrs. Ressler and Rosenthal are required to devote a substantial majority of their business time to the affairs of ACOF. Similarly, although the professional staff of our investment adviser will devote as much time to the management of the Company as appropriate to enable our investment adviser to perform its duties in accordance with the investment advisory and management agreement, the investment professionals of our investment adviser may have conflicts in allocating their time and services among the Company, on the one hand, and investment vehicles managed by Ares or one or more of its affiliates, on the other hand. These activities could be viewed as creating a conflict of interest insofar as the time and effort of the professional staff of our investment adviser and its officers and employees will not be devoted exclusively to the business of the Company but will instead be allocated between the business of the Company and the management of these other investment vehicles. However, Ares believes that the efforts of such individuals are synergistic with and beneficial to the affairs of Ares Capital, ACOF and these other investment vehicles managed by Ares or its affiliates.

        In addition, certain Ares funds may have investment objectives that compete or overlap with, and may from time to time invest in asset classes similar to those targeted by, Ares Capital. Consequently, we, on the one hand, and these other entities, may from time to time pursue the same or similar capital and investment opportunities. Ares and our investment adviser endeavor to allocate investment opportunities in a fair and equitable manner, and in any event consistent with any fiduciary duties owed to Ares Capital. Nevertheless, it is possible that we may not be given the opportunity to participate in certain investments made by investment funds managed by investment managers affiliated with Ares. In addition, there may be conflicts in the allocation of investment opportunities among us and the funds managed by us or one or more of our controlled affiliates or among the funds they manage. We may or may not participate in investments made by funds managed by us or one or more of our controlled affiliates.

        We have from time to time sold assets to certain of the vehicles managed by IHAM and, as part of our investment strategy, we may offer to sell additional assets to vehicles managed by us and/or one or more of our controlled affiliates (including IHAM) or we may purchase assets from vehicles managed by us and/or one or more of our controlled affiliates. In addition, vehicles managed by us or one or more of our controlled affiliates (including IHAM) may offer assets to or may purchase assets from one another. While assets may be sold or purchased at prices that are consistent with those that could be obtained from third parties in the marketplace, and although these types of transactions generally require approval of one or more independent parties, there may be an inherent conflict of interest in such transactions between us and funds managed by us or one of our controlled affiliates.

        We pay management and incentive fees to our investment adviser, and reimburse our investment adviser for certain expenses it incurs. In addition, investors in our common stock will invest on a gross basis and receive distributions on a net basis after expenses, resulting in, among other things, a lower rate of return than one might achieve if distributions were made on a gross basis.

        Our investment adviser's base management fee is based on a percentage of our total assets (other than cash or cash equivalents but including assets purchased with borrowed funds) and, consequently, our investment adviser may have conflicts of interest in connection with decisions that could affect our total assets, such as decisions as to whether to incur indebtedness or to make future investments.

        The part of the incentive fee payable by us to our investment advisor that relates to our pre-incentive fee net investment income is computed and paid on income that may include interest that is accrued but not yet received in cash. If a portfolio company defaults on a loan that is structured to provide accrued interest, it is possible that accrued interest previously used in the calculation of the incentive fee will become uncollectible.

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        Our investment advisory and management agreement renews for successive annual periods if approved by our board of directors or by the affirmative vote of the holders of a majority of our outstanding voting securities, including, in either case, approval by a majority of our directors who are not "interested persons" of the Company as defined in Section 2(a)(19) of the Investment Company Act. However, both we and our investment adviser have the right to terminate the agreement without penalty upon 60 days' written notice to the other party. Moreover, conflicts of interest may arise if our investment adviser seeks to change the terms of our investment advisory and management agreement, including, for example, the terms for compensation. See "Management—Investment Advisory and Management Agreement." While any material change to the investment advisory and management agreement must be submitted to stockholders for approval under the Investment Company Act, we may from time to time decide it is appropriate to seek stockholder approval to change the terms of the agreement.

        We are party to an administration agreement (as defined below), with our administrator, Ares Operations, a wholly owned subsidiary of Ares, pursuant to which our administrator furnishes us with administrative services and we pay our administrator at cost our allocable portion of overhead and other expenses (including travel expenses) incurred by our administrator in performing its obligations under our administration agreement, including our allocable portion of the cost of certain of our officers (including our chief compliance officer, chief financial officer, general counsel, secretary and treasurer) and their respective staffs, but not investment professionals.

        Our portfolio company, IHAM, is party to an administration agreement, referred to herein as the "IHAM administration agreement," with Ares Operations. Pursuant to the IHAM administration agreement, Ares Operations provides IHAM with administrative services and IHAM reimburses Ares Operations for all of the actual costs associated with such services, including Ares Operations' allocable portion of overhead and the cost of its officers and respective staff in performing its obligations under the IHAM administration agreement. Prior to entering into the IHAM administration agreement, IHAM was party to a services agreement with our investment adviser, pursuant to which our investment adviser provided similar services.

        We are party to an office lease that will expire in February 2026 pursuant to which we are leasing office facilities from a third party. We are also party to an office sublease with Ares Commercial Real Estate Management LLC ("ACREM"), the manager of Ares Commercial Real Estate Corporation, pursuant to which we are subleasing approximately 12% of ACREM's office space for a fixed rent equal to 12% of the basic annual rent payable by ACREM under its office lease, plus certain additional costs and expenses. We also entered into separate subleases with Ares Management and IHAM, pursuant to which Ares Management and IHAM sublease approximately 15% and 20%, respectively, of our New York office space, for a fixed rent equal to 15% and 20%, respectively, of the basic annual rent payable by us under our office lease, plus certain additional costs and expenses.

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        As a result of the arrangements described above, there may be times when the management team of Ares (including those members of management focused primarily on managing Ares Capital) has interests that differ from those of our stockholders, giving rise to a conflict.

        Our stockholders may have conflicting investment, tax and other objectives with respect to their investments in us. The conflicting interests of individual stockholders may relate to or arise from, among other things, the nature of our investments, the structure or the acquisition of our investments, and the timing of dispositions of our investments. As a consequence, conflicts of interest may arise in connection with decisions made by our investment adviser, including with respect to the nature or structuring of our investments, that may be more beneficial for one stockholder than for another stockholder, especially with respect to stockholders' individual tax situations. In selecting and structuring investments appropriate for us, our investment adviser will consider the investment and tax objectives of the Company and our stockholders, as a whole, not the investment, tax or other objectives of any stockholder individually.

Changes in laws or regulations governing our operations or the operations of our portfolio companies, changes in the interpretation thereof or newly enacted laws or regulations, such as the Dodd-Frank Act, and any failure by us or our portfolio companies to comply with these laws or regulations, could require changes to certain business practices of us or our portfolio companies, negatively impact the operations, cash flows or financial condition of us or our portfolio companies, impose additional costs on us or our portfolio companies or otherwise adversely affect our business or the business of our portfolio companies.

        We and our portfolio companies are subject to regulation by laws and regulations at the local, state, federal and, in some cases, foreign levels. These laws and regulations, as well as their interpretation, may be changed from time to time, and new laws and regulations may be enacted. Accordingly, any change in these laws or regulations, changes in their interpretation, or newly enacted laws or regulations and any failure by us or our portfolio companies to comply with these laws or regulations, could require changes to certain business practices of us or our portfolio companies, negatively impact the operations, cash flows or financial condition of us or our portfolio companies, impose additional costs on us or our portfolio companies or otherwise adversely affect our business or the business of our portfolio companies.

        On July 21, 2010, President Obama signed into law the Dodd-Frank Act. Many of the provisions of the Dodd-Frank Act have extended implementation periods and delayed effective dates and will require extensive rulemaking by regulatory authorities. While the impact of the Dodd-Frank Act on us and our portfolio companies may not be known for an extended period of time, the Dodd-Frank Act, including future rules implementing its provisions and the interpretation of those rules, along with other legislative and regulatory proposals directed at the financial services industry or affecting taxation that are proposed or pending in the U.S. Congress, may negatively impact the operations, cash flows or financial condition of us or our portfolio companies, impose additional costs on us or our portfolio companies, intensify the regulatory supervision of us or our portfolio companies or otherwise adversely affect our business or the business of our portfolio companies.

Our investment adviser's liability is limited under the investment advisory and management agreement, and we are required to indemnify our investment adviser against certain liabilities, which may lead our investment adviser to act in a riskier manner on our behalf than it would when acting for its own account.

        Our investment adviser has not assumed any responsibility to us other than to render the services described in the investment advisory and management agreement, and it will not be responsible for any action of our board of directors in declining to follow our investment adviser's advice or recommendations. Pursuant to the investment advisory and management agreement, our investment

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adviser and its members and their respective officers, managers, partners, agents, employees, controlling persons and members and any other person or entity affiliated with it will not be liable to us for their acts under the investment advisory and management agreement, absent willful misfeasance, bad faith, gross negligence or reckless disregard in the performance of their duties. We have agreed to indemnify, defend and protect our investment adviser and its members and their respective officers, managers, partners, agents, employees, controlling persons and members and any other person or entity affiliated with it with respect to all damages, liabilities, costs and expenses resulting from acts of our investment adviser not arising out of willful misfeasance, bad faith, gross negligence or reckless disregard in the performance of their duties under the investment advisory and management agreement. These protections may lead our investment adviser to act in a riskier manner when acting on our behalf than it would when acting for its own account. See "Risk Factors—Risks Relating to Our Investments—Our investment adviser's incentive fee may induce it to make certain investments, including speculative investments."

We may be obligated to pay our investment adviser incentive compensation even if we incur a loss.

        Our investment adviser is entitled to incentive compensation for each fiscal quarter in an amount equal to a percentage of the excess of our pre-incentive fee net investment income for that quarter (before deducting incentive compensation and certain other items) above a threshold return for that quarter. Our pre-incentive fee net investment income for incentive compensation purposes excludes realized and unrealized capital losses or depreciation and income taxes related to realized gains that we may incur in the fiscal quarter, even if such capital losses or depreciation and income taxes related to realized gains result in a net loss on our statement of operations for that quarter. Thus, we may be required to pay our investment adviser incentive compensation for a fiscal quarter even if there is a decline in the value of our portfolio or we incur a net loss for that quarter.

        Under the investment advisory and management agreement, we will defer cash payment of any incentive fee otherwise earned by our investment adviser if, during the most recent four full calendar quarter periods ending on or prior to the date such payment is to be made, the sum of (a) our aggregate distributions to our stockholders and (b) our change in net assets (defined as total assets less indebtedness and before taking into account any incentive fees payable during the period) is less than 7.0% of our net assets (defined as total assets less indebtedness) at the beginning of such period. These calculations will be adjusted for any share issuances or repurchases. Any deferred incentive fees will be carried over for payment in subsequent calculation periods to the extent such payment can then be made under the investment advisory and management agreement.

        If a portfolio company defaults on a loan that is structured to provide accrued interest, it is possible that accrued interest previously used in the calculation of the incentive fee will become uncollectible. Our investment adviser is not under any obligation to reimburse us for any part of the incentive fee it received that was based on accrued income that we never receive as a result of a default on the obligation that resulted in the accrual of such income.

We may not replicate Ares' historical success and our ability to enter into transactions with Ares and our other affiliates is restricted.

        We cannot assure you that Ares Capital will replicate Ares' historical success, and we caution you that our investment returns could be substantially lower than the returns achieved by other Ares managed funds.

        Further, we and certain of our controlled affiliates are prohibited under the Investment Company Act from knowingly participating in certain transactions with our upstream affiliates, or our investment adviser and its affiliates, without the prior approval of our independent directors and, in some cases, the SEC. Any person that owns, directly or indirectly, 5% or more of our outstanding voting securities

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is our upstream affiliate for purposes of the Investment Company Act and we are generally prohibited from buying or selling any security (other than our securities) from or to such affiliate, absent the prior approval of our independent directors. The Investment Company Act also prohibits "joint" transactions with an upstream affiliate, or our investment adviser or its affiliates, which could include investments in the same portfolio company (whether at the same or different times), without prior approval of our independent directors. In addition, we and certain of our controlled affiliates are prohibited from buying or selling any security from or to, or entering into joint transactions with, our investment adviser and its affiliates, or any person who owns more than 25% of our voting securities or is otherwise deemed to control, be controlled by, or be under common control with us, absent the prior approval of the SEC through an exemptive order (other than in certain limited situations pursuant to current regulatory guidance). The analysis of whether a particular transaction constitutes a joint transaction requires a review of the relevant facts and circumstances.

        We have applied for an exemptive order from the SEC that would permit us and certain of our controlled affiliates to co-invest with funds managed by Ares. Any such order, if issued, will be subject to certain terms and conditions and there can be no assurance that such order will be granted by the SEC. Accordingly, we cannot assure you that we or our controlled affiliates will be permitted to co-invest with funds managed by Ares, other than in the limited circumstances currently permitted by regulatory guidance or in the absence of a joint transaction.

As a result of the death of Kenneth R. Heitz, who was an independent director, we are not in compliance with certain NASDAQ Global Select Market listing requirements.

        Kenneth R. Heitz, who was an independent member of our board of directors, passed away on July 9, 2012. As a result of Mr. Heitz's death, we are no longer in compliance with NASDAQ Marketplace Rule 5605(b)(1), because a majority of our board of directors is no longer comprised of independent directors. We notified the NASDAQ Global Select Market that we intend to rely on the cure provisions of Rule 5605(b)(1)(A), which provides that we have until the earlier of our next annual shareholders meeting or July 9, 2013 to comply with the above-referenced listing requirements.

RISKS RELATING TO OUR INVESTMENTS

Declines in market prices and liquidity in the corporate debt markets can result in significant net unrealized depreciation of our portfolio, which in turn would reduce our net asset value.

        As a BDC, we are required to carry our investments at market value or, if no market value is ascertainable, at fair value as determined in good faith by or under the direction of our board of directors. We may take into account the following types of factors, if relevant, in determining the fair value of our investments: the enterprise value of a portfolio company (the entire value of the portfolio company to a market participant, including the sum of the values of debt and equity securities used to capitalize the enterprise at a point in time), the nature and realizable value of any collateral, the portfolio company's ability to make payments and its earnings and discounted cash flow, the markets in which the portfolio company does business, a comparison of the portfolio company's securities to similar publicly traded securities, changes in the interest rate environment and the credit markets generally that may affect the price at which similar investments would trade in their principal markets and other relevant factors. When an external event such as a purchase transaction, public offering or subsequent equity sale occurs, we use the pricing indicated by the external event to corroborate our valuation. While most of our investments are not publicly traded, applicable accounting standards require us to assume as part of our valuation process that our investments are sold in a principal market to market participants (even if we plan on holding an investment through its maturity). As a result, volatility in the capital markets can also adversely affect our investment valuations. Decreases in the market values or fair values of our investments are recorded as unrealized depreciation. The effect of all of these factors on our portfolio can reduce our net asset value by increasing net unrealized

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depreciation in our portfolio. Depending on market conditions, we could incur substantial realized losses and may suffer unrealized losses, which could have a material adverse impact on our business, financial condition and results of operations.

Economic recessions or downturns could impair our portfolio companies and harm our operating results.

        Many of our portfolio companies may be susceptible to economic downturns or recessions (including the economic downturn that began in 2007) and may be unable to repay our loans during these periods. Therefore, during these periods our non-performing assets may increase and the value of our portfolio may decrease if we are required to write down the values of our investments. Adverse economic conditions may also decrease the value of collateral securing some of our loans and the value of our equity investments. Economic slowdowns or recessions could lead to financial losses in our portfolio and a decrease in revenues, net income and assets. Unfavorable economic conditions also could increase our funding costs, limit our access to the capital markets or result in a decision by lenders not to extend credit to us. These events could prevent us from increasing investments and harm our operating results. We experienced to some extent such effects during the economic downturn that began in 2007 and may experience such effects again in any future downturn or recession.

        A portfolio company's failure to satisfy financial or operating covenants imposed by us or other lenders could lead to defaults and, potentially, acceleration of the time when the loans are due and foreclosure on its assets representing collateral for its obligations, which could trigger cross defaults under other agreements and jeopardize our portfolio company's ability to meet its obligations under the debt that we hold and the value of any equity securities we own. We may incur expenses to the extent necessary to seek recovery upon default or to negotiate new terms with a defaulting portfolio company.

Investments in privately held middle-market companies involve significant risks.

        We primarily invest in privately held U.S. middle-market companies. Investments in privately held middle-market companies involve a number of significant risks, including the following:

•

these companies may have limited financial resources and may be unable to meet their obligations, which may be accompanied by a deterioration in the value of any collateral and a reduction in the likelihood of us realizing any guarantees we may have obtained in connection with our investment;



•

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



•

they typically depend on the management talents and efforts of a small group of persons; therefore, the death, disability, resignation or termination of one or more of these persons could have a material adverse impact on our portfolio company and, in turn, on us;



•

there is generally little public information about these companies. These companies and their financial information are not subject to the Securities Exchange Act of 1934 (the "Exchange Act") and other regulations that govern public companies, and we may be unable to uncover all material information about these companies, which may prevent us from making a fully informed investment decision and cause us to lose money on our investments;



•

they generally have less predictable operating results and may require substantial additional capital to support their operations, finance expansion or maintain their competitive position;

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•

our executive officers, directors and our investment adviser may, in the ordinary course of business, be named as defendants in litigation arising from our investments in the portfolio companies; and



•

they may have difficulty accessing the capital markets to meet future capital needs.

Our debt investments may be risky and we could lose all or part of our investment.

        The debt that we invest in is typically not initially rated by any rating agency, but we believe that if such investments were rated, they would be below investment grade (rated lower than "Baa3" by Moody's Investors Service, lower than "BBB-" by Fitch Ratings or lower than "BBB-" by Standard & Poor's Ratings Services), which is an indication of having predominantly speculative characteristics with respect to the issuer's capacity to pay interest and repay principal. Indebtedness of below investment grade quality is regarded as having predominantly speculative characteristics with respect to the issuer's capacity to pay interest and repay principal. Therefore, our investments may result in an above average amount of risk and volatility or loss of principal. We also invest in assets other than first and second lien and mezzanine debt investments, including high-yield securities, U.S. government securities, credit derivatives and other structured securities and certain direct equity investments. These investments entail additional risks that could adversely affect our investment returns.

Investments in equity securities, many of which are illiquid with no readily available market, involve a substantial degree of risk.

        We may purchase common and other equity securities. Although common stock has historically generated higher average total returns than fixed income securities over the long-term, common stock also has experienced significantly more volatility in those returns and in recent years has significantly under performed relative to fixed income securities. The equity securities we acquire may fail to appreciate and may decline in value or become worthless and our ability to recover our investment will depend on our portfolio company's success. Investments in equity securities involve a number of significant risks, including:

•

any equity investment we make in a portfolio company could be subject to further dilution as a result of the issuance of additional equity interests and to serious risks as a junior security that will be subordinate to all indebtedness (including trade creditors) or senior securities in the event that the issuer is unable to meet its obligations or becomes subject to a bankruptcy process;



•

to the extent that the portfolio company requires additional capital and is unable to obtain it, we may not recover our investment; and



•

in some cases, equity securities in which we invest will not pay current dividends, and our ability to realize a return on our investment, as well as to recover our investment, will be dependent on the success of the portfolio company. Even if the portfolio company is successful, our ability to realize the value of our investment may be dependent on the occurrence of a liquidity event, such as a public offering or the sale of the portfolio company. It is likely to take a significant amount of time before a liquidity event occurs or we can otherwise sell our investment. In addition, the equity securities we receive or invest in may be subject to restrictions on resale during periods in which it could be advantageous to sell them.

        There are special risks associated with investing in preferred securities, including:

•

preferred securities may include provisions that permit the issuer, at its discretion, to defer distributions for a stated period without any adverse consequences to the issuer. If we own a

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preferred security that is deferring its distributions, we may be required to report income for tax purposes before we receive such distributions;

•

preferred securities are subordinated to debt in terms of priority to income and liquidation payments, and therefore will be subject to greater credit risk than debt;



•

preferred securities may be substantially less liquid than many other securities, such as common stock or U.S. government securities; and



•

generally, preferred security holders have no voting rights with respect to the issuing company, subject to limited exceptions.

        Additionally, when we invest in first and second lien senior loans or mezzanine debt, we may acquire warrants or other equity securities as well. Our goal is ultimately to dispose of such equity interests and realize gains upon our disposition of such 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 may invest, to the extent permitted by law, in the equity securities of investment funds that are operating pursuant to certain exceptions to the Investment Company Act and in advisers to similar investment funds and, to the extent we so invest, will bear our ratable share of any such company's expenses, including management and performance fees. We will also remain obligated to pay management and incentive fees to Ares Capital Management with respect to the assets invested in the securities and instruments of such companies. With respect to each of these investments, each of our common stockholders will bear his or her share of the management and incentive fee of Ares Capital Management as well as indirectly bearing the management and performance fees and other expenses of any such investment funds or advisers.

        As a result of the Allied Acquisition, Allied Capital's equity investments, including equity investments larger than those we have traditionally made and controlled portfolio company equity investments, became part of our portfolio. We continue to actively seek opportunities over time to dispose of certain of these investments and generally rotate them into higher-yielding first and second lien senior loans and mezzanine debt or other investments. However, there can be no assurance that this strategy will be successful.

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.

        If one of our portfolio companies were to go bankrupt, even though we may have structured our interest as senior debt, depending on the facts and circumstances, a bankruptcy court might recharacterize our debt holding as an equity investment and subordinate all or a portion of our claim to that of other creditors. In addition, lenders can be subject to lender liability claims for actions taken by them where they become too involved in the borrower's business or exercise control over the borrower. For example, we could become subject to a lender's liability claim, if, among other things, we actually render significant managerial assistance.

Our portfolio companies may incur debt or issue equity securities that rank equally with, or senior to, our investments in such companies.

        Our portfolio companies may have, or may be permitted to incur, other debt, or issue other equity securities, that rank equally with, or senior to, our investments. By their terms, such instruments may provide that the holders are entitled to receive payment of dividends, interest or principal on or before the dates on which we are entitled to receive payments in respect of our investments. These debt instruments would usually prohibit the portfolio companies from paying interest on or repaying our

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investments in the event and during the continuance of a default under such debt. Also, in the event of insolvency, liquidation, dissolution, reorganization or bankruptcy of a portfolio company, holders of securities ranking senior to our investment in that portfolio company typically are entitled to receive payment in full before we receive any distribution in respect of our investment. After repaying such holders, the portfolio company may not have any remaining assets to use for repaying its obligation to us. In the case of securities ranking equally with our investments, we would have to share on an equal basis any distributions with other security holders in the event of an insolvency, liquidation, dissolution, reorganization or bankruptcy of the relevant portfolio company.

        The rights we may have with respect to the collateral securing any junior priority loans we make to our portfolio companies may also be limited pursuant to the terms of one or more intercreditor agreements that we enter into with the holders of senior debt. Under such an intercreditor agreement, at any time that senior obligations are outstanding, we may forfeit certain rights with respect to the collateral to the holders of the senior obligations. These rights may include the right to commence enforcement proceedings against the collateral, the right to control the conduct of such enforcement proceedings, the right to approve amendments to collateral documents, the right to release liens on the collateral and the right to waive past defaults under collateral documents. We may not have the ability to control or direct such actions, even if as a result our rights as junior lenders are adversely affected.

When we are a debt or minority equity investor in a portfolio company, we are often not in a position to exert influence on the entity, and other equity holders and management of the company may make decisions that could decrease the value of our portfolio holdings.

        When we make debt or minority equity investments, we are subject to the risk that a portfolio company may make business decisions with which we disagree and the other equity holders and management of such company may take risks or otherwise act in ways that do not serve our interests. As a result, a portfolio company may make decisions that could decrease the value of our investment.

Our portfolio companies may be highly leveraged.

        Some of our portfolio companies may be highly leveraged, which may have adverse consequences to these companies and to us as an investor. These companies may be subject to restrictive financial and operating covenants and the leverage may impair these companies' ability to finance their future operations and capital needs. As a result, these companies' flexibility to respond to changing business and economic conditions and to take advantage of business opportunities may be limited. Further, a leveraged company's income and net assets will tend to increase or decrease at a greater rate than if borrowed money were not used.

Our investment adviser's incentive fee may induce it to make certain investments, including speculative investments.

        The incentive fee payable by us to Ares Capital Management may create an incentive for Ares Capital Management to make investments on our behalf that are risky or more speculative than would be the case in the absence of such compensation arrangement. The way in which the incentive fee payable to our investment adviser is determined, which is calculated as a percentage of the return on invested capital, may encourage our investment adviser to use leverage to increase the return on our investments. Under certain circumstances, the use of leverage may increase the likelihood of default, which would disfavor the holders of our common stock and the holders of securities convertible into our common stock. In addition, our investment adviser will receive the incentive fee based, in part, upon net capital gains realized on our investments. Unlike the portion of the incentive fee based on income, there is no hurdle rate applicable to the portion of the incentive fee based on net capital gains. As a result, our investment adviser may have a tendency to invest more in investments that are likely to result in capital gains as compared to income producing securities. Such a practice could result in our

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investing in more speculative securities than would otherwise be the case, which could result in higher investment losses, particularly during economic downturns.

        The part of the incentive fee payable by us that relates to our pre-incentive fee net investment income will be computed and paid on income that may include interest that is accrued but not yet received in cash. If a portfolio company defaults on a loan that is structured to provide accrued interest, it is possible that accrued interest previously used in the calculation of the incentive fee will become uncollectible. Our investment adviser is not under any obligation to reimburse us for any part of the incentive fee it received that was based on such accrued interest that we never actually receive.

        Because of the structure of the incentive fee, it is possible that we may have to pay an incentive fee in a quarter where we incur a loss. For example, if we receive pre-incentive fee net investment income in excess of the hurdle rate for a quarter, we will pay the applicable incentive fee even if we have incurred a loss in that quarter due to realized and/or unrealized capital losses. In addition, if market interest rates rise, we may be able to invest our funds in debt instruments that provide for a higher return, which would increase our pre-incentive fee net investment income and make it easier for our investment adviser to surpass the fixed hurdle rate and receive an incentive fee based on such net investment income.

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

        Our investment strategy contemplates potential investments in foreign companies. Investing in foreign companies may expose us to additional risks not typically associated with investing in U.S. companies. These risks include changes in exchange control regulations, political and social instability, expropriation, imposition of foreign taxes (potentially at confiscatory levels), less liquid markets, less available information than is generally the case in the United States, higher transaction costs, less government supervision of exchanges, brokers and 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, our investments that are 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. We may employ hedging techniques to minimize these risks, but we cannot assure you that such strategies will be effective or without risk to us.

We may expose ourselves to risks if we engage in hedging transactions.

        We have and may in the future enter into hedging transactions, which may expose us to risks associated with such transactions. We may utilize instruments such as forward contracts, currency options and interest rate swaps, caps, collars and floors to seek to hedge against fluctuations in the relative values of our portfolio positions from changes in currency exchange rates and market interest rates. Use of these hedging instruments may include counter-party credit risk.

        Hedging against a decline in the values of our portfolio positions does not eliminate the possibility of fluctuations in the values of such positions or prevent losses if the values of such positions decline. However, such hedging can establish other positions designed to gain from those same developments, thereby offsetting the decline in the value of such portfolio positions. Such hedging transactions may also limit the opportunity for gain if the values of the underlying portfolio positions should increase. Moreover, it may not be possible to hedge against an exchange rate or interest rate fluctuation that is so generally anticipated that we are not able to enter into a hedging transaction at an acceptable price.

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        The success of our hedging transactions will depend on our ability to correctly predict movements in currencies and interest rates. Therefore, while we may enter into such transactions to seek to reduce currency exchange rate and interest rate risks, unanticipated changes in currency exchange rates or interest rates may result in poorer overall investment performance than if we had not engaged in any such hedging transactions. In addition, the degree of correlation between price movements of the instruments used in a hedging strategy and price movements in the portfolio positions being hedged may vary. Moreover, for a variety of reasons, we may not seek to (or be able to) establish a perfect correlation between such hedging instruments and the portfolio holdings being hedged. Any such imperfect correlation may prevent us from achieving the intended hedge and expose us to risk of loss. In addition, it may not be possible to hedge fully or perfectly against currency fluctuations affecting the value of securities denominated in non-U.S. currencies because the value of those securities is likely to fluctuate as a result of factors not related to currency fluctuations. See also "Risk Factors—Risk Relating to Our Business—We are exposed to risks associated with changes in interest rates."

We may initially invest a portion of the net proceeds of offerings pursuant to this prospectus primarily in high-quality short-term investments, which will generate lower rates of return than those expected from the interest generated on first and second lien loans and mezzanine debt.

        We may initially invest a portion of the net proceeds of offerings primarily in cash, cash equivalents, U.S. government securities and other high-quality short-term investments. These securities may earn yields substantially lower than the income that we anticipate receiving once we are fully invested in accordance with our investment objective. As a result, we may not be able to achieve our investment objective and/or pay any dividends during this period or, if we are able to do so, such dividends may be substantially lower than the dividends that we expect to pay when our portfolio is fully invested. If we do not realize yields in excess of our expenses, we may incur operating losses and the market price of our shares may decline.

RISKS RELATING TO OFFERINGS PURSUANT TO THIS PROSPECTUS

Our shares of common stock have traded at a discount from net asset value and may do so again in the future, which could limit our ability to raise additional equity capital.

        Shares of closed-end investment companies frequently trade at a market price that is less than the net asset value that is attributable to those shares. This characteristic of closed-end investment companies is separate and distinct from the risk that our net asset value per share may decline. It is not possible to predict whether any shares of our common stock will trade at, above, or below net asset value. In the recent past, including during much of 2009, the stocks of BDCs as an industry, including at times shares of our common stock, traded below net asset value and at near historic lows as a result of concerns over liquidity, leverage restrictions and distribution requirements. When our common stock is trading below its net asset value per share, we will generally not be able to issue additional shares of our common stock at its market price without first obtaining approval for such issuance from our stockholders and our independent directors. At our 2012 annual stockholders meeting, subject to certain determinations required to be made by our board of directors, our stockholders approved our ability to sell or otherwise issue shares of our common stock, not exceeding 25% of our then outstanding common stock, at a price below the then current net asset value per share during a period beginning on June 4, 2012 and expiring on the earlier of June 4, 2013 and the date of our 2013 annual stockholders meeting.

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There is a risk that investors in our common stock may not receive dividends or that our dividends may not grow over time and that investors in our debt securities may not receive all of the interest income to which they are entitled.

        We intend to make distributions on a quarterly basis 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 make a specified level of cash distributions or year-to-year increases in cash distributions. If we declare a dividend and if more stockholders opt to receive cash distributions rather than participate in our dividend reinvestment plan, we may be forced to sell some of our investments in order to make cash dividend payments.

        In addition, due to the asset coverage test applicable to us as a BDC, we may be limited in our ability to make distributions. Further, if we invest a greater amount of assets in equity securities that do not pay current dividends, it could reduce the amount available for distribution. See "Price Range of Common Stock and Distributions."

        The above-referenced restrictions on distributions may also inhibit our ability to make required interest payments to holders of our debt, which may cause a default under the terms of our debt agreements. Such a default could materially increase our cost of raising capital, as well as cause us to incur penalties under the terms of our debt agreements.

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

        The Maryland General Corporation Law, our charter and our bylaws contain provisions that may discourage, delay or make more difficult a change in control of Ares Capital or the removal of our directors. We are subject to the Maryland Business Combination Act (the "Business Combination Act"), subject to any applicable requirements of the Investment Company Act. Our board of directors has adopted a resolution exempting from the Business Combination Act any business combination between us and any other person, subject to prior approval of such business combination by our board, including approval by a majority of our disinterested directors. If the resolution exempting business combinations is repealed or our board or disinterested directors do not approve a business combination, the Business Combination Act may discourage third parties from trying to acquire control of us and increase the difficulty of consummating such an offer. Our bylaws exempt from the Maryland Control Share Acquisition Act (the "Control Share Acquisition Act") acquisitions of our stock by any person. If we amend our bylaws to repeal the exemption from the Control Share Acquisition Act, the Control Share Acquisition Act also may make it more difficult for a third party to obtain control of us and increase the difficulty of consummating such an offer.

        We have also adopted measures that may make it difficult for a third party to obtain control of us, including provisions of our charter classifying our board of directors into three classes serving staggered three-year terms, and provisions of our charter authorizing our board of directors to classify or reclassify shares of our stock into one or more classes or series, to cause the issuance of additional shares of our stock, and to amend our charter from time to time, without stockholder approval, to increase or decrease the aggregate number of shares of stock or the number of shares of stock of any class or series that we have authority to issue. These provisions, as well as other provisions of our charter and bylaws, may discourage, delay, defer, make more difficult or prevent a transaction or a change in control that might otherwise be in the best interests of our stockholders.

Investing in our common stock may involve an above average 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 volatility or loss of principal. Our investments in

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portfolio companies may be highly speculative and aggressive and, therefore, an investment in our securities may not be suitable for someone with lower risk tolerance.

The market price of our common stock may fluctuate significantly.

        The capital and credit markets have experienced periods of extreme volatility and disruption over the past several years. The market price and liquidity of the market for shares of our common stock 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:

•

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



•

price and volume fluctuations in the overall stock market from time to time;



•

changes in law, regulatory policies or tax guidelines, or interpretations thereof, particularly with respect to RICs or BDCs;



•

loss of our RIC status;



•

changes in our earnings or variations in our operating results;



•

changes in the value of our portfolio of investments;



•

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



•

departure of key personnel of Ares;



•

operating performance of companies comparable to us;



•

short-selling pressure with respect to shares of our common stock or BDCs generally;



•

future sales of our securities convertible into or exchangeable or exercisable for our common stock or the conversion of such securities, including the Convertible Notes;



•

uncertainty surrounding the strength of the U.S. economic recovery;



•

concerns regarding European sovereign debt;



•

general economic trends and other external factors; and



•

loss of a major funding source.

        In the past, following periods of volatility in the market price of a company's securities, securities class action litigation has often been brought against that company. If our stock price fluctuates significantly, we may be the target of securities litigation in the future. Securities litigation could result in substantial costs and divert management's attention and resources from our business.

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

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appreciation in excess of their stated preference (other than convertible preferred stock that converts into common stock). In addition, under the Investment Company Act, preferred stock constitutes a "senior security" for purposes of the 200% asset coverage test.

The net asset value per share of our common stock may be diluted 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 securities to subscribe for or convertible into shares of our common stock.

        At our 2012 annual stockholders meeting, subject to certain determinations required to be made by our board of directors, our stockholders approved our ability to sell or otherwise issue shares of our common stock, not exceeding 25% of our then outstanding common stock, at a price below the then current net asset value per share during a period beginning on June 4, 2012 and expiring on the earlier of June 4, 2013 and the date of our 2013 annual stockholders meeting.

        In addition, at our 2009 annual stockholders meeting, our stockholders approved a proposal authorizing us to sell or otherwise issue warrants or securities to subscribe for or convertible into shares of our common stock subject to certain limitations (including, without limitation, that the number of shares issuable does not exceed 25% of our then outstanding common stock and that the exercise or conversion price thereof is not, at the date of issuance, less than the greater of the market value per share and the net asset value per share of our common stock). The authorization granted to sell or issue warrants or securities to subscribe for or convertible into shares of our common stock has no expiration.

        Any decision to sell shares of our common stock below its then current net asset value per share or securities to subscribe for or convertible into 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.

        If we were to sell shares of our common stock below its then current net asset value per share, such sales would result in an immediate dilution to the net asset value per share of our common stock. 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 the stockholders' interest in our earnings and assets and their voting interest in us than the increase in our assets resulting from such issuance. 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.

        In addition, if we issue warrants or securities to subscribe for or convertible into shares of our common stock, subject to certain limitations, the exercise or conversion price per share could be less than net asset value per share at the time of exercise or conversion (including through the operation of anti-dilution protections). Because we would incur expenses in connection with any issuance of such securities, such issuance could result in a dilution of the net asset value per share at the time of exercise or conversion. This dilution would include reduction in net asset value per share as a result of the proportionately greater decrease in the stockholders' interest in our earnings and assets and their voting interest than the increase in our assets resulting from such issuance.

        Further, if current stockholders of the Company do not purchase any shares to maintain their percentage interest, regardless of whether such offering is above or below the then current net asset value per share, their voting power will be diluted. For additional information and hypothetical examples of these risks, see "Sales of Common Stock Below Net Asset Value" and the prospectus supplement pursuant to which such sale is made.

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Your interest in us may be diluted if you do not fully exercise your subscription rights in any rights offering. In addition, if the subscription price is less than our net asset value per share, then you will experience an immediate dilution of the aggregate net asset value of your shares.

        In the event we issue subscription rights, stockholders who do not fully exercise their subscription rights should expect that they will, at the completion of a rights offering pursuant to this prospectus, own a smaller proportional interest in us than would otherwise be the case if they fully exercised their rights. We cannot state precisely the amount of any such dilution in share ownership because we do not know at this time what proportion of the shares will be purchased as a result of such rights offering.

        In addition, if the subscription price is less than the net asset value per share of our common stock, then our stockholders would experience an immediate dilution of the aggregate net asset value of their shares as a result of the offering. The amount of any decrease in net asset value is not predictable because it is not known at this time what the subscription price and net asset value per share will be on the expiration date of a rights offering or what proportion of the shares will be purchased as a result of such rights offering. Such dilution could be substantial. See "Risk Factors—Risks Relating to Offerings Pursuant to this Prospectus—The net asset value per share of our common stock may be diluted 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 securities to subscribe for or convertible into shares of our common stock" and "Sales of Common Stock Below Net Asset Value."

Investors in offerings of our common stock will likely incur immediate dilution upon the closing of such offering.

        We generally expect the public offering price of any offering of shares of our common stock to be higher than the book value per share of our outstanding common stock (unless we offer shares pursuant to a rights offering or after obtaining prior approval for such issuance from our stockholders and our independent directors). Accordingly, investors purchasing shares of common stock in offerings pursuant to this prospectus may pay a price per share that exceeds the tangible book value per share after such offering.

Our stockholders will experience dilution in their ownership percentage if they opt out of our dividend reinvestment plan.

        All dividends declared in cash payable to stockholders that are participants in our dividend reinvestment plan are automatically reinvested in shares of our common stock. As a result, our stockholders that opt out of our dividend reinvestment plan will experience dilution in their ownership percentage of our common stock over time.

Our stockholders may experience dilution upon the conversion of the Convertible Notes.

        The February 2016 Convertible Notes are convertible into shares of our common stock beginning August 15, 2015 or, under certain circumstances, earlier. The June 2016 Convertible Notes are convertible into shares of our common stock beginning on December 15, 2015 or, under certain circumstances, earlier. The 2017 Convertible Notes are convertible into shares of our common stock beginning on September 15, 2016 or, under certain circumstances, earlier. Upon conversion of the Convertible Notes, we have the choice to pay or deliver, as the case may be, at our election, cash, shares of our common stock or a combination of cash and shares of our common stock. The current conversion price of the February 2016 Convertible Notes is approximately $19.13 per share of common stock, the current conversion price of the June 2016 Convertible Notes is approximately $19.04 per share and the current conversion price of the 2017 Convertible Notes is approximately $19.34 per share, in each case subject to adjustment in certain circumstances. If we elect to deliver shares of common stock upon a conversion at the time our tangible book value per share exceeds the conversion

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price in effect at such time, our stockholders may incur dilution. In addition, our stockholders will experience dilution in their ownership percentage of common stock upon our issuance of common stock in connection with the conversion of the Convertible Notes and any dividends paid on our common stock will also be paid on shares issued in connection with such conversion after such issuance.

Our stockholders may receive shares of our common stock as dividends, which could result in adverse tax consequences to them.

        In order to satisfy the Annual Distribution Requirement applicable to RICs, we have the ability to declare a large portion of a dividend in shares of our common stock instead of in cash. As long as a portion of such dividend is paid in cash (which portion can be as low as 10% for dividends declared with respect to our taxable years ending on or before December 31, 2011) and certain requirements are met, the entire distribution would be treated as a dividend for U.S. federal income tax purposes. As a result, a stockholder would be taxed on 100% of the fair market value of the dividend on the date a stockholder received it in the same manner as a cash dividend, even though most of the dividend was paid in shares of our common stock.

Sales of substantial amounts of our common stock in the public market may have an adverse effect on the market price of our common stock.

        Sales of substantial amounts of our common stock, or the availability of such common stock for sale (including as a result of the conversion of our Convertible Notes into common stock), could adversely affect the prevailing market prices for our common stock. If this occurs and continues, it could impair our ability to raise additional capital through the sale of securities should we desire to do so.

The trading market or market value of our publicly issued debt securities may fluctuate.

        Our publicly issued debt securities may or may not have an established trading market. We cannot assure you that a trading market for our publicly issued debt securities will ever develop or be maintained if developed. In addition to our creditworthiness, many factors may materially adversely affect the trading market for, and market value of, our publicly issued debt securities. These factors include, but are not limited to, the following:

•

the time remaining to the maturity of these debt securities;



•

the outstanding principal amount of debt securities with terms identical to these debt securities;



•

the ratings assigned by national statistical ratings agencies;



•

the general economic environment;



•

the supply of debt securities trading in the secondary market, if any;



•

the redemption or repayment features, if any, of these debt securities;



•

the level, direction and volatility of market interest rates generally; and



•

market rates of interest higher or lower than rates borne by the debt securities.

        You should also be aware that there may be a limited number of buyers when you decide to sell your debt securities. This too may materially adversely affect the market value of the debt securities or the trading market for the debt securities.

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Terms relating to redemption may materially adversely affect your return on any debt securities that we may issue.

        If your debt securities are redeemable at our option, we may choose to redeem your debt securities at times when prevailing interest rates are lower than the interest rate paid on your debt securities. In addition, if your debt securities are subject to mandatory redemption, we may be required to redeem your debt securities also at times when prevailing interest rates are lower than the interest rate paid on your debt securities. 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 your debt securities being redeemed.

Our credit ratings may not reflect all risks of an investment in our debt securities.

        Our credit ratings are an assessment by third parties of our ability to pay our obligations. Consequently, real or anticipated changes in our credit ratings will generally affect the market value of our debt securities. Our credit ratings, however, may not reflect the potential impact of risks related to market conditions generally or other factors discussed above on the market value of or trading market for the publicly issued debt securities.

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FORWARD-LOOKING STATEMENTS

        Some of the statements in this prospectus constitute forward-looking statements, which relate to future events or our future performance or financial condition. The forward-looking statements contained in this prospectus involve a number of risks and uncertainties, including statements concerning:

•

our, or our portfolio companies', future business, operations, operating results or prospects;



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the return or impact of current and future investments;



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the impact of a protracted decline in the liquidity of credit markets on our business;



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the impact of fluctuations in interest rates on our business;



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the impact of changes in laws or regulations (including the interpretation thereof) governing our operations or the operations of our portfolio companies;



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the valuation of our investments in portfolio companies, particularly those having no liquid trading market;



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our ability to recover unrealized losses;



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market conditions and our ability to access alternative debt markets and additional debt and equity capital;



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our contractual arrangements and relationships with third parties;



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Middle East turmoil and the potential for rising energy prices and its impact on the industries in which we invest;



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the general economy and its impact on the industries in which we invest;



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the uncertainty surrounding the strength of the U.S. economic recovery;



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European sovereign debt issues;



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the financial condition of and ability of our current and prospective portfolio companies to achieve their objectives;



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our expected financings and investments;



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our ability to successfully complete and integrate any acquisitions;



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the adequacy of our cash resources and working capital;



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the timing, form and amount of any dividend distributions;



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the timing of cash flows, if any, from the operations of our portfolio companies; and



•

the ability of our investment adviser to locate suitable investments for us and to monitor and administer our investments.

        We use words such as "anticipates," "believes," "expects," "intends," "will," "should," "may" and similar expressions to identify forward-looking statements, although not all forward-looking statements include these words. Our actual results and condition could differ materially from those projected in the forward-looking statements for any reason, including the factors set forth in "Risk Factors" and elsewhere in this prospectus.

        The forward-looking statements included in this prospectus have been based on information available to us on the date of this prospectus, and we assume no obligation to update any such forward-looking statements. Although we undertake no obligation to revise or update any

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forward-looking statements, whether as a result of new information, future events or otherwise, you are advised to consult any additional disclosures that we may make directly to you or through reports that we have filed or in the future may file with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

        The forward-looking statements in this prospectus are excluded from the safe harbor protection provided by Section 27A of the Securities Act of 1933 (the "Securities Act") and Section 21E of the Exchange Act.

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USE OF PROCEEDS

        Unless otherwise specified in a prospectus supplement, we intend to use the net proceeds from the sale of our securities for general corporate purposes, which includes investing in portfolio companies in accordance with our investment objective. We also expect to use the net proceeds of an offering to repay or repurchase outstanding indebtedness, which may include indebtedness ($2.3 billion aggregate principal amount outstanding as of June 30, 2012) under (a) the Revolving Credit Facility ($295.0 million aggregate principal amount outstanding), (b) the Revolving Funding Facility ($348.0 million aggregate principal amount outstanding), (c) the SMBC Funding Facility ($107.0 million aggregate principal amount outstanding), (d) the 2022 Notes ($143.8 million aggregate principal amount outstanding), (e) the 2040 Notes ($200.0 million aggregate principal amount outstanding), (f) the 2047 Notes ($230.0 million aggregate principal amount outstanding), (g) the February 2016 Convertible Notes ($575.0 million aggregate principal amount outstanding), (h) the June 2016 Convertible Notes ($230.0 million aggregate principal amount outstanding) and (i) the 2017 Convertible Notes ($162.5 million aggregate principal amount outstanding).

        Subject to certain exceptions, the interest charged on the indebtedness incurred under the Revolving Credit Facility is based on LIBOR (one, two, three or six month) plus an applicable spread of 2.25% or a "base rate" (as defined in the agreements governing the Revolving Credit Facility) plus an applicable spread of 1.25%. As of June 30, 2012, the one, two, three and six month LIBOR were 0.25%, 0.34%, 0.46% and 0.73%, respectively. The Revolving Credit Facility matures on May 4, 2016. Subject to certain exceptions, the interest charged on the Revolving Funding Facility is based on LIBOR plus an applicable spread of 2.50% or on a "base rate" (as defined in the agreements governing the Revolving Funding Facility) plus an applicable spread of 1.50%. The Revolving Funding Facility is scheduled to expire on April 18, 2017 (subject to extension exercisable upon mutual consent). Subject to certain exceptions, the interest charged on the indebtedness incurred under the SMBC Funding Facility is based on one month LIBOR plus an applicable spread of 2.125% or a "base rate" (as defined in the agreements governing the SMBC Funding Facility) plus an applicable spread of 1.125%. The SMBC Funding Facility is scheduled to expire on January 20, 2020 (subject to two one-year extension options exercisable upon mutual consent). The interest charged on the Unsecured Notes and Convertible Notes is as follows: (a) 7.00% in the case of the 2022 Notes, (b) 7.75% in the case of the 2040 Notes, (c) 6.875% in the case of the 2047 Notes, (d) 5.75% in the case of the February 2016 Convertible Notes, (e) 5.125% in the case of the June 2016 Convertible Notes and (f) 4.875% in the case of the 2017 Convertible Notes. The 2022 Notes, 2040 Notes, 2047 Notes, February 2016 Convertible Notes, June 2016 Convertible Notes and 2017 Convertible Notes mature on February 15, 2022, October 15, 2040, April 15, 2047, February 1, 2016, June 1, 2016 and March 15, 2017, respectively. The supplement to this prospectus relating to an offering may more fully identify the use of the proceeds from such offering.

        We anticipate that substantially all of the net proceeds of an offering of securities pursuant to this prospectus and its related prospectus supplement will be used for the above purposes within three months of any such offering, depending on the availability of appropriate investment opportunities consistent with our investment objective, but no longer than within six months of any such offerings.

        Our primary focus is to generate current income and capital appreciation through investments in first and second lien senior loans and mezzanine debt and, to a lesser extent, equity securities of eligible portfolio companies. In addition to such investments, we may invest up to 30% of our portfolio in non-qualifying assets, as permitted by the Investment Company Act. See "Regulation." Specifically, as part of this 30% basket, we may invest in entities that are not considered "eligible portfolio companies" (as defined in the Investment Company Act), including companies located outside of the United States, entities that are operating pursuant to certain exceptions under the Investment Company Act, and publicly traded entities whose public equity market capitalization exceeds the levels provided for under the Investment Company Act. Pending such investments, we will invest a portion of the net

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proceeds primarily in cash, cash equivalents, U.S. government securities and other high-quality short-term investments. These securities generally earn yields substantially lower than the income that we anticipate receiving once we are fully invested in accordance with our investment objective. As a result, we may not be able to achieve our investment objective and/or pay any dividends during this period or, if we are able to do so, such dividends may be substantially lower than the dividends that we expect to pay when our portfolio is fully invested. If we do not realize yields in excess of our expenses, we may incur operating losses and the market price of our common stock and debt securities may decline. See "Regulation—Temporary Investments" for additional information about temporary investments we may make while waiting to make longer-term investments in pursuit of our investment objective.

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PRICE RANGE OF COMMON STOCK AND DISTRIBUTIONS

        Our common stock is traded on The NASDAQ Global Select Market under the symbol "ARCC." Our common stock has historically traded at prices both above and below our net asset value per share. It is not possible to predict whether our common stock will trade at, above or below net asset value. See "Risk Factors—Risks Relating to Offerings Pursuant to this Prospectus—Our shares of common stock have traded at a discount from net asset value and may do so again in the future, which could limit our ability to raise additional equity capital."

        The following table sets forth, for each fiscal quarter for the fiscal years ended December 31, 2010, 2011 and 2012, the net asset value per share of our common stock, the range of high and low closing sales prices of our common stock, the closing sales price as a percentage of net asset value and the dividends or distributions declared by us. On July 17, 2012, the last reported closing sales price of our common stock on The NASDAQ Global Select Market was $16.60 per share, which represented a premium of approximately 7.30% to the net asset value per share reported by us as of March 31, 2012.