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TABLE OF CONTENTS
TABLE OF CONTENTS

Table of Contents

Filed Pursuant to Rule 497
Registration Statement No. 333-231146

PROSPECTUS SUPPLEMENT
(to Prospectus dated April 30, 2019)

LOGO

Up to 1,000,000 Shares

Common Stock



          This prospectus supplement describes our Dividend Reinvestment and Direct Stock Purchase Plan, or the Plan, and 1,000,000 shares of our common stock, par value $0.01 per share, to be offered for purchase under the direct stock purchase feature of the Plan. The direct stock purchase feature of the Plan is designed to provide new investors and existing holders of our common stock with a convenient and economical method to purchase shares of our common stock. American Stock Transfer & Trust Company acts as the administrator for the Plan (the "Plan Administrator").

          Key aspects of the direct stock purchase feature of the Plan include:

          We are a principal investment firm primarily focused on providing customized debt and equity financing to lower middle market ("LMM") companies and debt capital to middle market ("Middle Market") companies. Our LMM companies generally have annual revenues between $10 million and $150 million, and our LMM portfolio investments generally range in size from $5 million to $50 million. Our Middle Market investments are made in businesses that are generally larger in size than our LMM portfolio companies, with annual revenues typically between $150 million and $1.5 billion, and our Middle Market investments generally range in size from $3 million to $20 million.

          The LMM and Middle Market securities in which we invest generally would be rated below investment grade if they were rated by rating agencies. Below investment grade securities, which are often referred to as "junk," have predominantly speculative characteristics with respect to the issuer's capacity to pay interest and repay principal. They may also be difficult to value and are illiquid.

          Our principal investment objective is to maximize our portfolio's total return by generating current income from our debt investments and capital appreciation from our equity and equity related investments, including warrants, convertible securities and other rights to acquire equity securities in a portfolio company.

          We are an internally managed, closed-end, non-diversified management investment company that has elected to be treated as a business development company under the Investment Company Act of 1940, as amended.

          Our common stock is listed on the NYSE under the symbol "MAIN." On May 9, 2019, the last reported sale price of our common stock on the NYSE was $39.63 per share, and the net asset value per share of our common stock on March 31, 2019 (the last date prior to the date of this prospectus supplement on which we determined our net asset value per share) was $24.41.

          Investing in our common stock involves a high degree of risk, and should be considered highly speculative. You should review carefully the risks and uncertainties, including the risk of leverage and dilution, described in the section titled "Supplementary Risk Factors" beginning on page S-7 of this prospectus supplement, the section titled "Risk Factors" in our most recently filed Annual Report on Form 10-K, and under similar headings in the other documents that are filed on or after the date hereof and incorporated by reference into this prospectus supplement and the accompanying prospectus before investing in our common stock.

          This prospectus supplement and the accompanying prospectus contain important information about us that a prospective investor should know before investing in our common stock. We may also authorize one or more free writing prospectuses to be provided to you in connection with this offering. You should carefully read this prospectus supplement, the accompanying prospectus, and any related free writing prospectus, and the documents incorporated by reference, before investing in our common stock. We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission, or SEC. This information is available free of charge by contacting us at 1300 Post Oak Boulevard, 8th Floor, Houston, Texas 77056 or by telephone at (713) 350-6000 or on our website at www.mainstcapital.com. Information contained on our website is not incorporated by reference into this prospectus supplement or the accompanying prospectus, and you should not consider that information to be part of this prospectus supplement or the accompanying prospectus. The SEC also maintains a website at www.sec.gov that contains such information.

          Neither the Securities and Exchange Commission nor any state securities commission, nor any other regulatory body, has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

   

The date of this prospectus supplement is May 10, 2019


Table of Contents


TABLE OF CONTENTS

Prospectus Supplement

 
  Page  

About this Document

    S-1  

Summary of the Direct Stock Purchase Feature of the Plan

    S-3  

Fees and Expenses

    S-5  

Supplementary Risk Factors

    S-7  

Use of Proceeds

    S-8  

Terms and Conditions of the Direct Stock Purchase Feature of the Plan

    S-9  

Legal Matters

    S-22  

Independent Registered Public Accounting Firm

    S-22  

Available Information

    S-22  

Incorporation by Reference

    S-22  


Prospectus

 
  Page  

Prospectus Summary

    1  

Fees and Expenses

    9  

Risk Factors

    11  

Cautionary Statement Concerning Forward-Looking Statements

    12  

Use of Proceeds

    13  

Price Range of Common Stock

    14  

Senior Securities

    15  

Portfolio Companies

    16  

Sales of Common Stock Below Net Asset Value

    48  

Dividend Reinvestment and Direct Stock Purchase Plan

    53  

Description of Common Stock

    54  

Description of Our Preferred Stock

    61  

Description of Our Subscription Rights

    62  

Description of Our Debt Securities

    63  

Material U.S. Federal Income Tax Considerations

    77  

Plan of Distribution

    85  

Custodian, Transfer and Distribution Paying Agent and Registrar

    87  

Brokerage Allocation and Other Practices

    87  

Legal Matters

    87  

Independent Registered Public Accounting Firm

    87  

Available Information

    88  

Incorporation by Reference

    88  

Privacy Notice

    89  

Table of Contents


ABOUT THIS DOCUMENT

        This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering of common stock and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into the accompanying prospectus and this prospectus supplement. The second part is the accompanying prospectus, which provides more information about us and related matters. To the extent the information contained in this prospectus supplement differs from the information contained in the accompanying prospectus or any document filed prior to the date of this prospectus supplement and incorporated by reference, the information in this prospectus supplement shall control. Generally, when we refer to this "prospectus," we are referring to both documents combined, together with any free writing prospectus that we have authorized for use in connection with this offering.

        You should rely only on the information included or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us that relates to this offering of common stock. We have not authorized any other person to provide you with different information or to make representations as to matters not stated in this prospectus supplement, the accompanying prospectus or in any free writing prospectus prepared by or on behalf of us that relates to this offering of common stock. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus supplement, the accompanying prospectus and any free writing prospectus prepared by or on behalf of us that relates to this offering of common stock do not constitute an offer to sell, or a solicitation of an offer to buy, any shares of our common stock by any person in any jurisdiction where it is unlawful for that person to make such an offer or solicitation or to any person in any jurisdiction to whom it is unlawful to make such an offer or solicitation. You should not assume that the information included in this prospectus supplement, the accompanying prospectus or in any such free writing prospectus is accurate as of any date other than their respective dates, or that any information incorporated by reference is accurate as of any date other than the date of the document incorporated by reference, regardless of the time of delivery of this prospectus supplement or of any of our securities.

Forward-Looking Statements

        Information included or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus relating to this offering of common stock may contain forward-looking statements, which can be identified by the use of forward-looking terminology such as "may," "will," "expect," "intend," "anticipate," "estimate," or "continue" or the negative thereof or other variations thereon or comparable terminology. The matters described in the sections titled "Supplementary Risk Factors" in this prospectus supplement, "Risk Factors" in the accompanying prospectus and "Risk Factors" in our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC, or in any free writing prospectus relating to this offering and certain other factors noted throughout or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectus relating to this offering constitute cautionary statements identifying important factors with respect to any such forward-looking statements, including certain risks and uncertainties that could cause actual results to differ materially from those in such forward-looking statements. We undertake no obligation to revise or update any forward-looking statements but advise you to consult any additional disclosures that we may make directly to you or through reports that we may file in the future with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

        You should not place undue reliance on our forward-looking statements because the matters they describe are subject to known and unknown risks, uncertainties and other unpredictable factors, many of which are beyond our control. In addition to the information included or incorporated by reference

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in this prospectus supplement, please read carefully the sections titled "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" in our most recent Annual Report on Form 10-K and in other documents we may file with the SEC, as well as the section titled "Cautionary Statement Concerning Forward-Looking Statements" in the accompanying prospectus, before making an investment in our common stock.

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SUMMARY OF THE DIRECT STOCK PURCHASE FEATURE OF THE PLAN

        The following summary highlights selected information about the direct stock purchase feature of the Plan, but may not contain all of the information that may be important to you. You should carefully read the detailed description of the direct stock purchase feature of the Plan contained in this prospectus supplement before you decide to participate in the direct stock purchase feature of the Plan.

Participation

        Current Stockholders.    If you currently own shares in the Company, you can participate in the direct stock purchase feature of the Plan by completing an authorization form and submitting it to American Stock Transfer & Trust Company LLC, the Plan Administrator. The initial investment for existing record holders is $100. Please see Question 6 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan" for more detailed information.

        New Investors.    If you do not own any shares in the Company, you can participate in the direct stock purchase feature of the Plan by enrolling in the Plan and making an initial purchase of the Company's shares through the direct stock purchase feature of the Plan with a minimum initial investment of at least $250 (or $100 if you sign up for automatic monthly investments), but not more than $25,000. Once you are a stockholder, the minimum purchase amount is reduced to $100. Please see Question 6 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan" for more detailed information.

Advantages and Disadvantages

        The primary advantages of the direct stock purchase feature of the Plan are as follows:

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        The risks associated with participating in the direct stock purchase feature of the Plan are described under the heading "Supplementary Risk Factors" beginning on page S-7 of this prospectus supplement.

Source of Shares

        The Plan Administrator will purchase shares directly from us as newly issued common stock, in the open market or in privately negotiated transactions with third parties. Please see Questions 10 and 12 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan" for more detailed information.

Purchase Price

        The purchase price for shares under the direct stock purchase feature of the Plan depends on whether the Plan Administrator obtains your shares by purchasing them directly from us, in the open market or in privately negotiated transactions with third parties:

Tracking Your Investments

        As a participant in the direct stock purchase feature of the Plan, you will receive periodic statements showing the details of each transaction and the share balance in your Plan account. Please see Question 22 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan" for more detailed information.

Plan Administrator

        We have appointed American Stock Transfer & Trust Company LLC as the administrator of the Plan. Please see Question 2 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan" for more detailed information.

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FEES AND EXPENSES

        The following table is intended to assist you in understanding the costs and expenses that an investor in this offering will bear directly or indirectly. We caution you that some of the percentages indicated in the table below are estimates and may vary. Except where the context suggests otherwise, whenever this prospectus supplement contains a reference to fees or expenses paid by "you," "us" or "Main Street," or that "we" will pay fees or expenses, stockholders will indirectly bear such fees or expenses as investors in us.

Stockholder Transaction Expenses:

       

Sales load (as a percentage of offering price)

    %(1)

Offering expenses (as a percentage of offering price)

    0.19 %(2)

Dividend reinvestment and direct stock purchase plan expenses

    %(3)

Total stockholder transaction expenses (as a percentage of offering price)

    0.19 %

Annual Expenses of the Company (as a percentage of net assets attributable to common stock):

       

Operating expenses

    2.68 %(4)

Interest payments on borrowed funds

    3.37 %(5)

Income tax expense

    0.40 %(6)

Acquired fund fees and expenses

    0.30 %(7)

Total annual expenses

    6.75 %

(1)
Purchasers of shares of common stock through the direct stock purchase feature of the Plan will not pay any sales load.

(2)
The percentage reflects estimated offering expenses payable by us of approximately $75,000 for the estimated duration of this offering.

(3)
The expenses of administering our dividend reinvestment and direct stock purchase plan are included in operating expenses. Additional costs may be charged to participants in the Plan for certain types of transactions described in Question 21 under the section entitled "Terms and Conditions of the Direct Stock Purchase Feature of the Plan."

(4)
Operating expenses in this table represent the estimated expenses of Main Street and its consolidated subsidiaries.

(5)
Interest payments on borrowed funds represent our estimated annual interest payments on borrowed funds based on current debt levels as adjusted for projected increases (but not decreases) in debt levels over the next twelve months.

(6)
Income tax expense relates to the accrual of (a) deferred tax provision (benefit) primarily related to loss carryforwards, timing differences in net unrealized appreciation or depreciation and other temporary book tax differences from our portfolio investments held in Taxable Subsidiaries and (b) excise, state and other taxes. Deferred taxes are non-cash in nature and may vary significantly from period to period. We are required to include deferred taxes in calculating our annual expenses even though deferred taxes are not currently payable or receivable. Due to the variable nature of deferred tax expense, which can be a large portion of the income tax expense, and the difficulty in providing an estimate for future periods, this income tax expense estimate is based upon the actual amount of income tax expense for the year ended December 31, 2018.

(7)
Acquired fund fees and expenses represent the estimated indirect expense incurred due to investments in other investment companies and private funds.

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Example

        The following example demonstrates the projected dollar amount of total cumulative expenses that would be incurred over various periods with respect to a hypothetical investment in our common stock. In calculating the following expense amounts, we have assumed we would have no additional leverage and that our annual operating expenses would remain at the levels set forth in the table above.

 
  1 Year   3 Years   5 Years   10 Years  

You would pay the following expenses on a $1,000 investment, assuming a 5.0% annual return

  $ 69   $ 199   $ 325   $ 621  

        The example and the expenses in the table above should not be considered a representation of our future expenses, and actual expenses may be greater or less than those shown. While the example assumes, as required by the SEC, a 5.0% annual return, our performance will vary and may result in a return greater or less than 5.0%. In addition, while the example assumes reinvestment of all dividends at net asset value, participants in the dividend reinvestment feature of our dividend reinvestment and direct stock purchase plan will receive a number of shares of our common stock, determined by dividing the total dollar amount of the dividend payable to a participant by (i) the market price per share of our common stock at the close of trading on a valuation date determined by our Board of Directors for each dividend in the event that we use newly issued shares to satisfy the share requirements of the dividend reinvestment plan or (ii) the average purchase price of all shares of common stock purchased by the Plan Administrator in the event that shares are purchased in the open market to satisfy the share requirements of the dividend reinvestment feature of the dividend reinvestment and direct stock purchase plan, which may be at, above or below net asset value. See "Dividend Reinvestment and Direct Stock Purchase Plan" in the accompanying prospectus for additional information regarding the dividend reinvestment feature of the Plan.

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SUPPLEMENTARY RISK FACTORS

        Investing in our common stock, including through the direct stock purchase feature of the Plan, involves a high degree of risk. In addition to the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, you should carefully consider the following supplementary risk factors together with the risk factors and other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus before making an investment. These risks are not the only risks we face. Additional risks and uncertainties not presently known to us or not presently deemed material by us might also impair our operations and performance. If any of these risks occur, our business, financial condition and results of operations could be materially and adversely affected. In such case, the market price of our common stock could decline, and you may lose part or all of your investment.

         No interest will be paid on funds pending investment.

        If you wish to make regular periodic purchases without writing checks, you can authorize automatic monthly withdrawals from your U.S. bank account. Participants' bank accounts are debited on the 10th day of each month (or, if that day is not a business day, then on the prior business day) and funds will be invested beginning on the next applicable Cash Purchase Investment Date. Pending such investment, no interest is paid on optional cash investments held by the Plan Administrator. In addition, optional cash payments of less than the amounts required by the Plan and that portion of any optional cash payment which exceeds the maximum monthly purchase limit of $25,000, are subject to return to you without interest.

         Participants will have no control over the purchase or sale price for shares acquired or disposed of through the Plan.

        Participants have no control over the share price or the timing of the purchase or sale of Plan shares. Participants cannot designate a specific price or a specific date at which to purchase or sell shares of our common stock or the selection of a broker/dealer through or from whom purchases or sales are made. Participants will not know the exact number of shares purchased until after any particular Cash Purchase Investment Date. In addition, because the Plan Administrator must receive funds for a cash purchase prior to the actual Cash Purchase Investment Date of the common stock, your investments may be exposed to changes in market conditions.

         No assurance of a profit or protection from losses on Shares purchased under the direct stock purchase feature of the Plan.

        Other than as described above, the risks related to your investment in the direct stock purchase feature of the Plan is no different from any investment in shares of our common stock held by you. If you choose to participate in the direct stock purchase feature of the Plan, then you should recognize that none of us, our subsidiaries and affiliates, nor the Plan Administrator can assure you of a profit or protect you against loss on the shares that you purchase under the direct stock purchase feature of the Plan. You bear the risk of loss in value and enjoy the benefits of gains with respect to all of your shares.

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USE OF PROCEEDS

        We intend to initially use the net proceeds from this offering to repay outstanding debt borrowed under our revolving credit facility (the "Credit Facility"). However, through re-borrowing of the initial repayments under our Credit Facility, we intend to use the net proceeds from this offering to make investments in accordance with our investment objective and strategies described in this prospectus supplement, the accompanying prospectus and any free writing prospectus relating to this offering, to make investments in marketable securities and idle funds investments, which may include investments in secured intermediate term bank debt, rated debt securities and other income producing investments, to pay our operating expenses and other cash obligations, and for general corporate purposes. Our ability to achieve our investment objective may be limited to the extent that the net proceeds from an offering, pending full investment, are held in interest bearing deposits or other short term instruments. See "Risk Factors—Risks Relating to Our Securities—We may be unable to invest a significant portion of the net proceeds from an offering or from exiting an investment or other capital on acceptable terms, which could harm our financial condition and operating results" in our most recently filed Annual Report on Form 10-K, as well as in subsequent filings with the SEC.

        On May 9, 2019, we had approximately $58.0 million outstanding under our Credit Facility. Our Credit Facility matures in September 2023, unless extended, and bears interest, at our election, on a per annum basis at a rate equal to the applicable LIBOR rate plus (i) 1.875% (or the applicable base rate plus 0.875%), as long as we meet certain agreed upon excess collateral and maximum leverage requirements or (ii) 2.0% (or the applicable base rate plus 1.0%) otherwise. Amounts repaid under our Credit Facility will remain available for future borrowings.

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TERMS AND CONDITIONS OF THE DIRECT
STOCK PURCHASE FEATURE OF THE PLAN

        The following are material terms and conditions of the direct stock purchase feature of the Plan.

PURPOSE

1.
What is the purpose of the direct stock purchase feature of the Plan?

        The primary purpose of the direct stock purchase feature of the Plan is to give holders of shares of our common stock and new investors a convenient and economical way to acquire additional shares of our common stock by making optional cash payments to purchase shares of our common stock. In this way, the direct stock purchase feature of the Plan is intended to benefit our long-term investors by allowing them to increase their investment in our common stock. The direct stock purchase feature of the Plan also provides us with a cost-efficient way to raise additional capital through the direct sale of our common stock to participants in the direct stock purchase feature of the Plan.

ADMINISTRATION

2.
Who administers the Plan?

        American Stock Transfer & Trust Company LLC has been appointed as administrator of the Plan. You should send all correspondence with the Plan Administrator to:

        All transaction processing should be directed to:

        Please mention Main Street Capital Corporation and this Plan in all correspondence with the Plan Administrator. In addition, you may call the Plan Administrator at 1-866-706-8371 or contact the Plan Administrator via the internet at www.astfinancial.com.

        The Company may replace the Plan Administrator at any time upon written notice to the Plan Administrator and may designate another qualified administrator as successor Plan Administrator for all or a part of the Plan Administrator's functions under the Plan. All participants would be notified of any such change. If the Company changes the Plan Administrator, references in this prospectus to Plan Administrator shall be deemed to be references to the successor Plan Administrator, unless the context requires otherwise.

3.
What are the responsibilities of the Plan Administrator?

        The Plan Administrator's responsibilities principally include:

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        Holding Shares.    If you purchase shares through optional cash payments and do not choose to have the dividends or distributions that are paid with respect to these shares reinvested, you must indicate that the shares are not to be enrolled in the dividend reinvestment feature of the Plan program. The Plan Administrator will hold any shares you choose to enroll in the dividend reinvestment feature of the Plan and will register them in the Plan Administrator's name (or that of its nominee) as your agent.

        Receipt of Dividends or Distributions.    As record holder for the Plan shares, the Plan Administrator will receive dividends or distributions on all Plan shares held on the record date, will credit these dividends or distributions to your Plan account on the basis of whole or fractional Plan shares held in such account, and will automatically reinvest such dividends or distributions in additional common stock unless you select the cash payment only option on the authorization form or direct the Plan Administrator that you wish to receive cash payments only (which instructions can always be changed by providing notice to the Plan Administrator). Any remaining portion of cash dividends or distributions not designated for reinvestment will be sent to you. The record date associated with a particular dividend or distribution is referred to in this Plan as a "dividend record date."

        Other Responsibilities.    The Plan Administrator also acts as dividend disbursing agent, transfer agent and registrar for our common stock.

        Replacement Administrator.    If the Plan Administrator resigns or otherwise ceases to act as Plan Administrator, we will appoint a new Plan Administrator to administer the Plan.

ELIGIBILITY AND ENROLLMENT

4.
Who is eligible to participate in the direct stock purchase feature of the Plan?

        Record Owners.    You are a record owner if you own shares of our common stock that are registered in your name with our transfer agent. If you are a record owner, you may participate directly in any or all of the features of the direct stock purchase feature of the Plan.

        Beneficial Owners.    You are a beneficial owner if you own shares of our common stock that are registered in the name of a broker, bank or other nominee. If you are a beneficial owner, you must either (i) become a record owner by having one or more shares transferred into your own name, or (ii) coordinate your participation in the direct stock purchase feature of the Plan through the broker, bank or other nominee in whose name your common stock is held.

        New Investors.    If you do not currently own shares of our common stock, you can participate in the Plan by making an initial purchase of shares of our common stock through the direct stock purchase feature of the Plan with a minimum investment of $250 (or $100 if you sign up for automatic monthly investments).

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5.
Are there limitations on participation in the direct stock purchase feature of the Plan other than those described under Question 4?

Regulations in certain countries may limit or prohibit participation in this type of plan. Persons residing outside the United States who wish to participate in the direct stock purchase feature of the Plan should first determine whether they are subject to any governmental regulation prohibiting their participation.

        You may not participate in the direct stock purchase feature of the Plan if it would be unlawful for you to do so in the jurisdiction where you are a citizen or, if you are a corporation or other entity, where you are organized or domiciled. If you are a citizen of, or organized or domiciled in, a country other than the U.S., you should independently confirm that by participating in the direct stock purchase feature of the Plan you will not violate local laws governing, among other matters, taxes, currency and exchange controls, stock registration and foreign investments. We reserve the right to terminate participation of any participant if we deem it advisable under any foreign laws or regulations.

        The direct stock purchase feature of the Plan is designed for long-term investors who would like to invest and build ownership of shares of our common stock over time. The direct stock purchase feature of the Plan is not intended to provide stockholders with a mechanism for generating short-term profits through rapid turnover of shares acquired at a discount. Further, the direct stock purchase feature of the Plan's intended purpose precludes any individual or entity from establishing a series of related accounts for the purpose of conducting arbitrage operations or exceeding the optional monthly cash investment limit. You should not use the direct stock purchase feature of the Plan to engage in short-term trading activities that could change the normal trading volume of shares of our common stock. If you engage in short-term trading activities, we may prevent you from participating in the direct stock purchase feature of the Plan. We reserve the right, in our sole discretion, to modify, deny, suspend or terminate participation by a Plan participant who, in our determination, is using the direct stock purchase feature of the Plan for purposes inconsistent with the intended purpose of the direct stock purchase feature of the Plan or which adversely affect the price of our common stock. In such an event, the Plan Administrator will notify the participant in writing of its action and will continue to hold the participant's shares in book-entry form, but will no longer reinvest the participant's dividends or distributions, or accept optional cash investments from the participant.

6.
How do I become a participant in the direct stock purchase feature of the Plan?

        Record Holders.    Record holders may join the plan by completing and signing an authorization form and returning it to the Plan Administrator or by following the enrollment procedures specified on the Plan Administrator's website at www.astfinancial.com. Authorization forms may be obtained at any time by written request, by telephoning the Plan Administrator at the address and telephone number provided in Question 2, or via the internet at the Plan Administrator's website. The initial minimum investment for existing record holders is $100.

        Beneficial Holders.    A beneficial holder may request that the number of shares the beneficial holder wishes to be enrolled in the direct stock purchase feature of the Plan be re-registered by the broker, bank or other nominee in the beneficial holder's own name as record owner in order to participate directly in the direct stock purchase feature of the Plan. Alternatively, beneficial holders who wish to join the direct stock purchase feature of the Plan may instruct their broker, bank or other nominee to arrange participation in the direct stock purchase feature of the Plan on the beneficial holder's behalf. The broker, bank or other nominee should then make arrangements with its securities depository, and the securities depository will provide the Plan Administrator with the information necessary to allow the beneficial holder to participate in the direct stock purchase feature of the Plan.

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        New Investors.    If you do not currently own any shares of our common stock, you may enroll in the direct stock purchase feature of the Plan by making an initial purchase of shares of our common stock through the direct stock purchase feature of the Plan with a minimum investment of $250 (or $100 if you sign up for automatic monthly investments), but your initial investment cannot exceed $25,000. The new investor should complete the portions of the authorization form for a new investor wishing to become a participant and should designate the amount of the initial investment in our common stock. At the same time, the new participant may designate all, some portion or none of the purchased shares to be enrolled in the dividend reinvestment program. The authorization form should be returned to the Plan Administrator, with payment, on or before the applicable dates described in Question 7. The new investors may also follow the enrollment procedures specified on the Plan Administrator's website at www.astfinancial.com to join the direct stock purchase feature of the Plan. Online enrollment should be completed on or before the applicable dates described in Question 7. Once you are a stockholder, the minimum purchase amount is reduced to $100.

7.
When will my participation in the direct stock purchase feature of the Plan begin?

        If you have submitted your authorization form to make automatic monthly investments under the direct stock purchase feature of the Plan, the Plan Administrator must receive authorization two business days before the Cash Purchase Investment Date.

        In the case of new investors making an initial investment, both the authorization form and full payment of their designated initial investment must be received two business days before the Cash Purchase Investment Date.

        Once you enroll in the direct stock purchase feature of the Plan, you will remain enrolled in the direct stock purchase feature of the Plan until you withdraw, we terminate your participation or we terminate the Plan.

8.
What does the Plan Administrator's website provide?

        Instead of submitting an authorization form, you can participate in the direct stock purchase feature of the Plan by accessing the Plan Administrator's website at www.astfinancial.com. The following services are available to you online:

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OPTIONAL CASH INVESTMENTS

9.
How do I make optional cash investments?

        Once you have enrolled in the direct stock purchase feature of the Plan by submitting an authorization form, you may make optional cash investments at any time in three ways:

        Insufficient Funds.    A $25 fee will be assessed if any check or deposit is returned unpaid or if an automatic withdrawal from your bank account fails due to insufficient funds. In addition, the Plan Administrator will consider null and void the request for any optional cash investment associated with insufficient funds and will immediately remove any shares already credited to your account in anticipation of receiving those funds. The foregoing fee and any other incidental costs associated with the insufficient funds will be collected by the Plan Administrator through the sale of an appropriate number of shares from your Plan account. If the net proceeds from the sale of those shares are insufficient to satisfy the balance of the uncollected amounts, the Plan Administrator may sell additional shares from your account as necessary to satisfy the uncollected balance.

        No interest is paid on your payment pending its investment in shares of our common stock. During the period that an optional cash investment is pending, the collected funds in the possession of the Plan Administrator may be invested in money market mutual funds registered under the Investment Company Act of 1940 (including those of an affiliate of the Plan Administrator or for which the Plan Administrator or any of its affiliates provides management advisory or other services) consisting entirely of (i) direct obligations of the United States, or (ii) obligations fully guaranteed by the United States. The Plan Administrator will retain any investment income from such investments and will bear the risk of loss from such investments.

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10.
When will shares be purchased?

        If the Plan Administrator acquires shares directly from us, then the date on which the Plan Administrator will make such cash investments, which we refer to as the "Cash Purchase Investment Date," will be the 15th of each month (or the previous NYSE trading day if the 15th day is not an NYSE trading day). If the Plan Administrator acquires shares from parties other than us, it will attempt to buy shares of our common stock in the open market through a registered broker-dealer or privately negotiated transaction. Such purchases may begin before or after the Cash Purchase Investment Date, and will be completed no later than thirty (30) days following such date, except where completion at a later date is necessary or advisable under any applicable U.S. federal or state securities laws or regulations.

11.
What are the minimum and maximum amounts for optional cash investments under the direct stock purchase feature of the Plan?

        Optional cash investments are subject to a monthly minimum purchase requirement of $100 and a maximum purchase limit of $25,000. For purposes of the Plan, we may aggregate all dividend reinvestments and optional cash investments for participants with more than one account. We reserve the right to not honor requests for investments if we deem that an individual is using the Plan as a trading account. The Plan has been designed to offer individuals with the opportunity to build equity and not as trading account. In addition, all Plan accounts that we believe to be under common control or management or to have common ultimate beneficial ownership may be aggregated. Unless we have determined, in our sole discretion, that reinvestment of dividends and optional cash investments for each such account would be consistent with the purposes of the Plan, we have the right to aggregate all such accounts and to return, without interest, within 30 days of receipt, any amounts in excess of the investment limitations applicable to a single account received in respect of all such accounts.

COMMON STOCK USED TO SATISFY SHARE OBLIGATIONS

12.
What is the source of shares to be purchased under the direct stock purchase feature of the Plan?

        Either newly issued shares or shares purchased on the open market or in privately negotiated transactions with third parties, at our or the Plan Administrator's discretion, will be used to satisfy any share obligations under the Plan (subject to the regulatory matter described in Question 14 below). Shares issued directly by us will consist of authorized but unissued shares of common stock. We may change the source of the common stock for the Plan, in our sole discretion, without providing you notice that we are doing so.

13.
At what price will shares be issued or purchased?

If the shares of our common stock are issued directly by us, the issue price will be the closing price per share reported on the NYSE on the NYSE trading day immediately preceding the Cash Purchase Investment Date, subject to any discount rate (ranging from 0% to 5%, exclusive of any applicable fees we may pay on your behalf) as we shall determine in our sole discretion. You will not be charged any fees or commissions with respect to such purchases. Any discount rate will apply uniformly to all optional cash investments by participants on any given Cash Purchase Investment Date.

If the shares of our common stock are purchased in the open market or in privately negotiated transactions, the purchase price will be the weighted average price paid per share for all the shares purchased in connection with such purchases, subject to any discount rate (ranging from 0% to 5%, exclusive of any applicable brokerage or other fees we may pay on your behalf) as we shall determine in our sole discretion. Any discount rate will apply uniformly to all optional cash investments by participants on any given Cash Purchase Investment Date. We will pay on your behalf any and all brokerage commissions incurred with respect to such purchases.

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        We may, at our sole discretion, offer a discount of up to 5% of the market price, as calculated as set forth herein (exclusive of any applicable fees we may pay on your behalf), on issuances or purchases of common stock under the direct stock purchase feature of the Plan. We are not required to issue or sell shares at a discount under the direct stock purchase feature of the Plan or to pay a discount with respect to shares purchased by the Plan Administrator in the open market. If we implement discounts on any feature of the direct stock purchase feature of the Plan, any such discounts will be made at our sole discretion; and the discount rate we may offer will be subject to change or discontinuance at our discretion and without prior notice to participants in the direct stock purchase feature of the Plan. The discount rate, if any, will be determined by us from time to time based on a review of current market conditions, the level of participation in the direct stock purchase feature of the Plan, our current and projected capital needs and other factors that we deem to be relevant. Any discounts that we are offering under the Plan will be disclosed on the Plan Administrator's website at www.astfinancial.com.

14.
Are there any other limits on the purchase of shares of common stock under the Plan?

        We are prohibited from selling shares of our common stock at a price that is, after deducting any selling commissions, less than the net asset value per share of our common stock at the time of the sale, except (i) with the requisite approval of our common stockholders or (ii) under such other circumstances as the SEC may permit. In addition, we cannot issue shares of our common stock below net asset value unless our Board of Directors determines that it would be in our and our stockholders' best interests to do so. We did not seek stockholder authorization to issue common stock at a price below net asset value per share at our 2019 annual meeting of stockholders because our common stock price per share has been trading significantly above the current net asset value per share of our common stock, but we may seek such authorization at future annual meetings or special meetings of stockholders.

        Sales by us of our common stock at a discount from our net asset value pose potential risks for our existing stockholders whether or not they participate in the offering, as well as for new investors who participate in the offering. See "Sales of Common Stock Below Net Asset Value" in the accompanying prospectus.

STOCK CERTIFICATES AND SAFEKEEPING

15.
Will I receive certificates for shares purchased through the direct stock purchase feature of the Plan?

        Normally, common stock purchased for you under the direct stock purchase feature of the Plan will be held in the name of the Plan Administrator or its nominee. The Plan Administrator will credit the shares to your account for the direct stock purchase feature of the Plan in "book-entry" form. This service protects against loss, theft or destruction of certificates evidencing common stock.

16.
Can I get certificates if I want them?

        No certificates will be issued to you for shares in the Plan unless you submit a written request to the Plan Administrator or, in certain cases, until your participation in the direct stock purchase feature of the Plan is terminated. At any time, you may request the Plan Administrator to send a certificate for some or all of the whole shares credited to your account. This request should be mailed to the Plan Administrator at the address set forth in the answer to Question 2 or made via the internet on the Plan Administrator's website at www.astfinancial.com. There is no fee for this service. Any remaining whole shares and any fractions of shares will remain credited to your Plan account. Certificates for fractional shares will not be issued under any circumstances.

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17.
May I deposit stock certificates I currently hold into my Plan account for safekeeping?

        You may also elect to deposit with the Plan Administrator certificates for common stock that you own and that are registered in your name for safekeeping under the plan for a fee of $7.50 payable each time you deposit certificates with the Plan Administrator. The Plan Administrator will credit the common stock represented by the certificates to your account in "book-entry" form and will combine the shares with any whole and fractional shares then held in your Plan account. In addition to protecting against the loss, theft or destruction of your certificates, this service is convenient if and when you sell shares of common stock through the Plan. Because you bear the risk of loss in sending certificates to the Plan Administrator, you should send certificates by registered mail, return receipt requested, and properly insured to the address specified in Question 2 above.

18.
In whose name will certificates be registered when issued?

        Your Plan account will be maintained in the name in which your certificates were registered at the time of your enrollment in the direct stock purchase feature of the Plan. Stock certificates for those shares purchased under the direct stock purchase feature of the Plan will be similarly registered when issued upon your request. If your shares are held through a broker, bank or other nominee, such request must be placed through your broker, bank or other nominee.

SALE AND TRANSFER OF SHARES

19.
How can I sell shares?

        You may instruct the Plan Administrator to sell all or any part of the shares held in your Plan account by doing any of the following:

        If there is more than one individual owner on the Plan account, all participants must authorize the transaction and sign the instruction. As with issuances and purchases, the Plan Administrator aggregates all requests to sell shares and then sells the total share amount on the open market through a broker. Sales will be made daily, unless the Plan Administrator, at its discretion, determines to sell shares less frequently (but not later than five trading days after receipt) if the total number of the shares to be sold is not sufficient.

        If you sell or transfer only a portion of the shares in your Plan account, you will remain a participant in the direct stock purchase feature of the Plan and may continue to make optional cash investments and reinvest dividends or distributions. The Plan Administrator will continue to reinvest the dividends or distributions on the shares credited to your account unless you notify the Plan Administrator that you wish to withdraw from the dividend reinvestment feature of the Plan.

        The Plan requires you to pay all costs associated with the sale of your shares under the Plan. You will receive the proceeds of the sale, less a $15 service fee per transaction and a $0.10 per share commission paid to the Plan Administrator and less any other applicable fees by check. A Form 1099-B will be mailed to you in February of each year related to your sales of shares in the prior year for income tax purposes.

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        Termination of Account Upon Sale of All Shares.    If the Plan Administrator sells all shares held in your Plan account, the Plan Administrator will automatically terminate your account. In this case, you will have to complete and file a new authorization form to rejoin the direct stock purchase feature of the Plan.

        Timing and Control.    Because the Plan Administrator will sell the shares on behalf of the Plan, neither we nor any participant in the Plan have the authority or power to control the timing or pricing of shares sold or the selection of the broker making the sales. Therefore, you will not be able to precisely time your sales through the Plan, and will bear the market risk associated with fluctuation in the price of our shares. That is, if you send in a request to sell shares, it is possible that the market price of our shares could go down or up before the broker sells your shares and the per share sales price you receive will be the average price of all shares sold for the Plan participants with respect to that sale date. In addition, you will not earn interest on a sales transaction.

        Alternatively, you can transfer some or all of the shares held in your Plan account to your account with a broker or bank, who can then sell the shares for you. If you need additional assistance regarding the transfer of your shares, please telephone the Plan Administrator, and consult your broker or bank about the fees and expenses related to their sale of your shares.

The price of our common stock fluctuates on a daily basis. The price may rise or fall after you submit your request to sell and prior to the ultimate sale of your shares of our common stock. The price risk will be borne solely by you. You cannot revoke your request to sell once it is made. The Plan Administrator will report to both the IRS and the participant Cost Basis for shares purchased or sold.

TERMINATION OF PARTICIPATION

20.
How do I terminate my participation in the direct stock purchase feature of the Plan?

        You may discontinue your participation in the direct stock purchase feature of the Plan at any time by notifying the Plan Administrator in writing at its mailing address or via its internet address specified in the answer to Question 2. Upon termination of your Plan account, you will receive a certificate for the whole shares held for you under the Plan free of charge. A cash payment will be made for any fractional shares held in your account at the time of termination based on the current market value less any applicable sales fees. Alternatively, if you so direct, the Plan Administrator will sell all or part of the shares credited to your Plan account by using the transaction stub on the bottom of your statement and mailing it to the address listed in Question 2. You may also make this request via the Plan Administrator's internet site at www.astfinancial.com.

FEES AND COMMISSIONS

21.
What are the costs of participating in the direct stock purchase feature of the Plan?

        You will not pay any trading fees, brokerage commissions or service fees on common stock purchased through the direct stock purchase feature of the Plan. We will pay all costs of administration of the Plan. You will, however, be responsible for any trading fees, brokerage commissions or service fees paid in connection with your sale of shares from the Plan. Please refer to the following tabular

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summary of Plan fees and commissions for more information regarding the current costs of participating in the direct stock purchase feature of the Plan:


Summary of Fees and Commissions

Enrollment fee for new investors:

  None

Issuance or purchase of shares by or from us:

  Paid by the Company

Purchase of shares in the open market or in privately negotiated transactions:

  Paid by the Company

Sale of shares (partial or full):

  $15.00 per transaction

Trading fees (applicable when shares are sold in the open market):

  $0.10 per share

Termination fee:

  $15.00 per transaction

Gift or transfer of shares:

  None

Deposit of stock certificates for safekeeping:

  $7.50 per deposit

Issuance of share certificates:

  None

Returned checks for insufficient funds or rejected automatic withdrawals:

  $25.00

Duplicate statements:

  $25.00 (current year free)

        The Plan Administrator will deduct the applicable fees or commissions from the proceeds of the sale.

        We and the Plan Administrator reserve the right to amend or modify this Plan Service Fee schedule at any time and from time to time.

REPORTS AND NOTICES TO PARTICIPANTS

22.
How will I keep track of my investments?

        The Plan Administrator will mail Plan statements after each investment. In addition, a notice will be mailed to you after each issue or purchase, which will include the number of shares issued or purchased and the issue or purchase price. You may also view your transaction history online by logging into your account. Details available online include stock price and transaction type and date.

You should retain these statements to determine the tax cost basis of the shares purchased for your account under the Plan. In addition, you will receive copies of other communications sent to our stockholders, including our annual report to stockholders, the notice of annual meeting and proxy statement in connection with our annual meeting of stockholders and Internal Revenue Service information for reporting dividends paid.

        You can also view your account history and balance online by accessing the Plan Administrator's website at www.astfinancial.com.

23.   Where will notices be sent?

        The Plan Administrator will address all of its notices to you at your last known address. You should notify the Plan Administrator promptly, in writing, of any change of address.

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FEDERAL TAX CONSEQUENCES

24.
What are some of the U.S. federal income tax consequences of a stockholder's participation in the direct stock purchase feature of the Plan?

        A summary of the U.S. federal income tax consequences of holding shares of our common stock is set forth in the section titled "Material U.S. Federal Income Tax Considerations" in the accompanying prospectus. We advise you to consult your own tax advisors to determine the tax consequences particular to your situation, including any applicable state, local or foreign income and other tax consequences that may result from your participation in the direct stock purchase feature of the Plan and your subsequent sale of shares of common stock acquired pursuant to the direct stock purchase feature of the Plan.

25.
What are the effects of the U.S. federal income tax withholding provisions applicable to U.S. stockholders?

        A summary of the effects of the U.S. federal income tax withholding provisions applicable to U.S. stockholders is set forth in the section titled "Material U.S. Federal Income Tax Considerations" in the accompanying prospectus.

OTHER INFORMATION

26.
How can I vote my shares?

        You will receive proxy material for all shares in your Plan account. You may vote your shares of common stock either by designating the vote of the shares by proxy or by voting the shares in person at the meeting of stockholders. The proxy will be voted in accordance with your direction. If you do not provide voting instructions but timely and properly submit your proxy, all of your shares will be voted in accordance with the recommendations of the board of directors. If you do not return the proxy card or if you return it unsigned, none of your shares will be voted unless you vote in person at the meeting of stockholders.

27.
If we have a rights offering related to the common stock, how will a stockholder's entitlement be computed?

        Your entitlement in a rights offering related to the common stock will be based upon the number of whole shares credited to your Plan account. In the event of a rights offering, transaction processing may be curtailed or suspended by the Plan Administrator for a short period of time following the dividend record date for such action to permit the Plan Administrator to calculate the rights allocable to each account.

        Transaction processing may be curtailed or suspended until the completion of any rights offering.

28.
What happens if we declare a dividend payable in stock or declare a stock split?

        Stock Dividends and Stock Splits.    If dividends or distributions are paid in the form of shares of our common stock, or if shares of our common stock are distributed in connection with any stock split or similar transaction, each account balance will be adjusted to reflect the receipt of shares of our common stock paid or distributed. You will receive a statement indicating the number of shares or amount of cash dividends or distributions paid as a result of the transaction. Transaction processing may either be curtailed or suspended until the completion of any stock dividend, stock split or corporate action.

        Other Capitalization Changes.    If there occurs any other transaction that results in the number of outstanding shares of our common stock being increased or decreased, such as a recapitalization,

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reclassification, reverse stock split or other combination of shares of our common stock, or other increase or decrease in shares of our common stock effectuated without receipt of consideration by us, each account balance will be adjusted to reflect the results of such transaction. You will receive a statement indicating the effects of such transaction on your account balance.

29.
Can the Plan be amended, modified, suspended or terminated?

        We reserve the right to amend, modify, suspend or terminate the Plan at any time in our sole discretion. You will receive written notice of any material amendment, modification, suspension or termination. We and the Plan Administrator also reserve the right to change any administrative procedures of the Plan in our discretion.

        If we terminate the Plan, you will receive a certificate for all whole shares of common stock held in your Plan account and a check representing the value of any fractional shares based on the then-current market price. We also will return to you any uninvested dividends or distributions or optional cash payments held in your Plan account.

        We reserve the right to terminate American Stock Transfer & Trust Company LLC as Plan Administrator and appoint another institution to serve as Plan Administrator, or to administer the Plan ourselves. All participants will receive notice of any such change, which may be by e-mail to participants electing to receive communications electronically of any such change.

30.
Are there any risks associated with the Plan?

        See "Supplementary Risk Factors" elsewhere in this prospectus supplement. Otherwise, your investment through the direct stock purchase feature of the Plan is no different from any investment in shares of our common stock held by you. If you choose to participate in the direct stock purchase feature of the Plan, then you should recognize that none of us, our subsidiaries and affiliates, nor the Plan Administrator can assure you of a profit or protect you against loss on the shares that you purchase under the direct stock purchase feature of the Plan. You bear the risk of loss in value and enjoy the benefits of gains with respect to all of your shares. You need to make your own independent investment and participation decisions consistent with your situation and needs. None of us, our subsidiaries and affiliates, nor the Plan Administrator can guarantee liquidity in the markets, and the value and marketability of your shares may be adversely affected by market conditions. For more information regarding risks relating to an investment in shares of our common stock, see "Supplementary Risk Factors" beginning on page S-7 of this prospectus supplement, "Risk Factors" in the accompanying prospectus and "Risk Factors" in our most recent Annual Report on Form 10-K and under similar headings in the other documents filed by us with the SEC on or after the date hereof and incorporated by reference into this prospectus supplement and the accompanying prospectus.

        Plan accounts are not insured or protected by the Securities Investor Protection Corporation or any other entity and are not guaranteed by the FDIC or any government agency.

        Neither we, our subsidiaries, our affiliates, nor the Plan Administrator will be liable for any act, or for any failure to act, as long as we or they have made good faith efforts to carry out the terms of the Plan, as described in this prospectus supplement and the accompanying prospectus and on the forms that are designed to accompany each investment or activity.

        In addition, the purchase price for shares acquired through the direct stock purchase feature of the Plan will vary and cannot be predicted. The purchase price may be different from (more or less than) the price of acquiring shares on the open market on the relevant date. Your investment in direct stock purchase feature of the Plan shares will be exposed to changes in market conditions and changes in the market value of the shares. Your ability to sell—both as to timing and pricing terms and related expenses—or otherwise liquidate shares under the Plan is subject to the terms of the Plan and the

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withdrawal procedures. Also, no interest will be paid on dividends, distributions, cash or other funds held by the Plan Administrator pending investment or sale.

31.
What are the responsibilities of Main Street and the Plan Administrator?

        Neither we, our subsidiaries, our affiliates, nor the Plan Administrator will be liable for any act, or for any failure to act, as long as we or they have made good faith efforts to carry out the terms of the direct stock purchase feature of the Plan, as described in this prospectus and on the forms that are designed to accompany each investment or activity. This limitation of liability includes, but is not limited to, any claims of liability for:

        We, any of our agents and the Plan Administrator, will not have any duties, responsibilities or liabilities other than those expressly set forth in the Plan or as imposed by applicable laws, including U.S. federal and state securities laws. Since the Plan Administrator has assumed all responsibility for administering the Plan, we specifically disclaim any responsibility for any of the Plan Administrator's actions or inactions in connection with the administration of the Plan. None of our directors, officers, employees or stockholders will have any personal liability under the Plan.

        We, any of our agents and the Plan Administrator, will be entitled to rely on completed forms and the proof of due authority to participate in the direct stock purchase feature of the Plan, without further responsibility of investigation or inquiry.

32.
How will you interpret and regulate the Plan?

        Our officers are authorized to take any actions that are consistent with the Plan's terms and conditions. We reserve the right to interpret and regulate the Plan as we deem necessary and desirable in connection with the Plan's operations. Any such determination by us will be conclusive and binding on Plan participants.

33.
What law governs the Plan?

        The laws of the State of New York govern the Plan.

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LEGAL MATTERS

        Certain legal matters regarding the shares of common stock offered hereby will be passed upon for us by Dechert LLP, Washington D.C.

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        The consolidated financial statements, financial highlights and Schedule 12-14 of Main Street Capital Corporation appearing in our Annual Report on Form 10-K for the year ended December 31, 2018 have been audited by Grant Thornton LLP, an independent registered public accounting firm, and incorporated in this prospectus supplement by reference. Such consolidated financial statements are incorporated by reference in reliance on the report of Grant Thornton LLP given on their authority as experts in accounting and auditing. The senior securities table of Main Street Capital Corporation, included in the accompanying prospectus and elsewhere in the registration statement, has been so included in reliance upon the report of Grant Thornton LLP, an independent registered public accounting firm, as stated in their report related thereto.

        Grant Thornton LLP's principal business address is Grant Thornton Tower, 171 North Clark, Suite 200, Chicago, Illinois, 60601.

AVAILABLE INFORMATION

        This prospectus supplement and the accompanying prospectus constitute part of a universal shelf registration statement on Form N-2 that we have filed with the SEC, together with any and all amendments and related exhibits, under the Securities Act. The registration statement contains additional information about us and our shares of common stock being offered by this prospectus supplement. Statements contained herein concerning any document filed as an exhibit are not necessarily complete, and, in each instance, reference is made to the copy of such document filed as an exhibit to the registration statement. Each such statement is qualified in its entirety by such reference.

        We file with or submit to the SEC annual, quarterly and current reports, proxy statements and other information meeting the informational requirements of the Exchange Act. The SEC maintains an Internet site that contains reports, proxy and information statements and other information filed electronically by us with the SEC, which are available free of charge on the SEC's website at www.sec.gov. This information is also available free of charge by contacting us at 1300 Post Oak Boulevard, 8th Floor, Houston, Texas 77056 or by telephone at (713) 350-6000 or on our website at www.mainstcapital.com. Information contained on our website is not incorporated by reference into this prospectus supplement or the accompanying prospectus, and you should not consider that information to be part of this prospectus supplement or the accompanying prospectus.

INCORPORATION BY REFERENCE

        We incorporate by reference in this prospectus supplement the documents listed below and any reports and other documents we file with the SEC pursuant to Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act after the date of this prospectus supplement and prior to the termination of this offering (such reports and other documents deemed to be incorporated by reference in this prospectus supplement and to be part hereof from the date of filing of such reports and other documents); provided, however, that any document, report, exhibit (or portion of any of the foregoing) or other information "furnished" to the SEC pursuant to the Exchange Act shall not be incorporated by reference into this prospectus supplement:

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        To obtain copies of these filings, see "Available Information" in this prospectus supplement.

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PROSPECTUS

$1,500,000,000

LOGO

Common Stock
Preferred Stock
Subscription Rights
Debt Securities



           We may offer, from time to time in one or more offerings, up to $1,500,000,000 of our common stock, preferred stock, subscription rights or debt securities, which we refer to, collectively, as the "securities." Our securities may be offered at prices and on terms to be disclosed in one or more supplements to this prospectus. The offering price per share of our common stock, less any underwriting commissions or discounts, will not be less than the net asset value per share of our common stock at the time of the offering, except (i) with the requisite approval of our common stockholders or (ii) under such other circumstances as the Securities and Exchange Commission may permit. We did not seek stockholder authorization to issue common stock at a price below net asset value per share at our 2018 annual meeting of stockholders, and we are not seeking such approval at our 2019 annual meeting of stockholders, because our common stock price per share has been trading significantly above the current net asset value per share of our common stock, but we may seek such authorization at future annual meetings or special meetings of stockholders. Sales of common stock at prices below net asset value per share dilute the interests of existing stockholders, have the effect of reducing our net asset value per share and may reduce our market price per share. In addition, we have received stockholder approval to issue warrants, options or rights to subscribe for, convert to, or purchase shares of our common stock at a price per share below the net asset value per share subject to the applicable requirements of the Investment Company Act of 1940, as amended. There is no expiration date on our ability to issue such warrants, options, rights or convertible securities based on this stockholder approval. Moreover, continuous sales of common stock below net asset value may have a negative impact on total returns and could have a negative impact on the market price of our shares of common stock. See "Sales of Common Stock Below Net Asset Value."

           Shares of closed-end investment companies such as us frequently trade at a discount to their net asset value. This risk is separate and distinct from the risk that our net asset value per share may decline. We cannot predict whether our common stock will trade above, at or below net asset value. You should read carefully the information contained or incorporated by reference in this prospectus, the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering before you invest in our common stock.

           Our securities may be offered to one or more purchasers directly by us, through agents designated from time to time by us, or to or through underwriters or dealers. The prospectus supplement relating to the offering will identify any agents or underwriters involved in the sale of our securities, and will disclose any applicable purchase price, fee, commission or discount arrangement between us and our agents or underwriters or among our underwriters or the basis upon which such amount may be calculated. See "Plan of Distribution."

           We are a principal investment firm primarily focused on providing customized debt and equity financing to lower middle market ("LMM") companies and debt capital to middle market ("Middle Market") companies. Our LMM companies generally have annual revenues between $10 million and $150 million, and our LMM portfolio investments generally range in size from $5 million to $50 million. Our Middle Market investments are made in businesses that are generally larger in size than our LMM portfolio companies, with annual revenues typically between $150 million and $1.5 billion, and our Middle Market investments generally range in size from $3 million to $20 million.

           The LMM and Middle Market securities in which we invest generally would be rated below investment grade if they were rated by rating agencies. Below investment grade securities, which are often referred to as "junk," have predominantly speculative characteristics with respect to the issuer's capacity to pay interest and repay principal. They may also be difficult to value and are illiquid.

           Our principal investment objective is to maximize our portfolio's total return by generating current income from our debt investments and capital appreciation from our equity and equity related investments, including warrants, convertible securities and other rights to acquire equity securities in a portfolio company.

           We are an internally managed, closed-end, non-diversified management investment company that has elected to be treated as a business development company under the Investment Company Act of 1940, as amended.

           Our common stock is listed on the New York Stock Exchange ("NYSE") under the symbol "MAIN." On April 29, 2019, the last reported sale price of our common stock on the NYSE was $39.27 per share, and the net asset value per share of our common stock on December 31, 2018 (the last date prior to the date of this prospectus on which we determined our net asset value per share) was $24.09.



           Investing in our securities involves a high degree of risk, and should be considered highly speculative. You should review carefully the risks and uncertainties, including the risk of leverage and dilution, described in the section titled "Risk Factors" included in, or incorporated by reference into, the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings in the other documents that are incorporated by reference into this prospectus before investing in our securities.

           This prospectus describes some of the general terms that may apply to an offering of our securities. We will provide the specific terms of these offerings and securities in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update, or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement, and any related free writing prospectus, and the documents incorporated by reference, before buying any of the securities being offered. We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission, or SEC. This information is available free of charge by contacting us at 1300 Post Oak Boulevard, 8th Floor, Houston, Texas 77056 or by telephone at (713) 350-6000 or on our website at www.mainstcapital.com. Information contained on our website is not incorporated by reference into this prospectus, and you should not consider that information to be part of this prospectus. The SEC also maintains a website at www.sec.gov that contains such information.

           Neither the Securities and Exchange Commission nor any state securities commission, nor any other regulatory body, has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.



   

The date of this prospectus is April 30, 2019


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TABLE OF CONTENTS

 
  Page  

Prospectus Summary

    1  

Fees and Expenses

    9  

Risk Factors

    11  

Cautionary Statement Concerning Forward-Looking Statements

    12  

Use of Proceeds

    13  

Price Range of Common Stock

    14  

Senior Securities

    15  

Portfolio Companies

    16  

Sales of Common Stock Below Net Asset Value

    48  

Dividend Reinvestment and Direct Stock Purchase Plan

    53  

Description of Common Stock

    54  

Description of Our Preferred Stock

    61  

Description of Our Subscription Rights

    62  

Description of Our Debt Securities

    63  

Material U.S. Federal Income Tax Considerations

    77  

Plan of Distribution

    85  

Custodian, Transfer and Distribution Paying Agent and Registrar

    87  

Brokerage Allocation and Other Practices

    87  

Legal Matters

    87  

Independent Registered Public Accounting Firm

    87  

Available Information

    88  

Incorporation by Reference

    88  

Privacy Notice

    89  

        This prospectus is part of an automatic registration statement that we have filed with the Securities and Exchange Commission, or SEC, using the "shelf" registration process as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended (the "Securities Act"). Under this shelf registration statement, we may offer, from time to time in one or more offerings, up to $1,500,000,000 of our securities, either individually or in combination with other securities described in this prospectus, on terms to be determined at the time of the offering. This prospectus provides you with a general description of the securities that we may offer. Each time we use this prospectus to offer securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. In a prospectus supplement or free writing prospectus, we may also add, update, or change any of the information contained in this prospectus or in the documents we have incorporated by reference into this prospectus. This prospectus, together with the applicable prospectus supplement, any related free writing prospectus, and the documents incorporated by reference into this prospectus and the applicable prospectus supplement, will include all material information relating to the applicable offering. Before buying any of the securities being offered, you should carefully read both this prospectus and the applicable prospectus supplement and any related free writing prospectus, together with the additional information described in the section titled "Available Information."

        This prospectus may contain estimates and information concerning our industry that are based on industry publications and reports. This information involves many assumptions and limitations, and you are cautioned not to give undue weight to these estimates. We have not independently verified the accuracy or completeness of the data contained in these industry publications and reports. The industry in which we operate is subject to a high degree of uncertainty and risk due to a variety of factors, including those described in the section titled "Risk Factors," that could cause results to differ materially from those expressed in these publications and reports.

        This prospectus includes summaries of certain provisions contained in some of the documents described in this prospectus, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the


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documents referred to herein have been filed, will be filed, or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described in the section titled "Available Information."

        You should rely only on the information included or incorporated by reference in this prospectus, any prospectus supplement or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We have not authorized any dealer, salesperson or other person to provide you with different information or to make representations as to matters not stated in this prospectus, any prospectus supplement or in any free writing prospectus prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus, any applicable prospectus supplement and any free writing prospectus prepared by or on behalf of us or to which we have referred you do not constitute an offer to sell, or a solicitation of an offer to buy, any securities by any person in any jurisdiction where it is unlawful for that person to make such an offer or solicitation or to any person in any jurisdiction to whom it is unlawful to make such an offer or solicitation. You should not assume that the information included or incorporated by reference in this prospectus or any prospectus supplement or in any such free writing prospectus is accurate as of any date other than their respective dates.


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PROSPECTUS SUMMARY

        This summary highlights information included elsewhere in this prospectus or incorporated by reference. It is not complete and may not contain all of the information that you should consider before making your investment decision. You should carefully read the entire prospectus, the applicable prospectus supplement, and any related free writing prospectus, including the risks of investing in our securities discussed in the section titled "Risk Factors" in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. Before making your investment decision, you should also carefully read the information incorporated by reference into this prospectus, including our financial statements and related notes, and the exhibits to the registration statement of which this prospectus is a part. Any yield information contained or incorporated by reference in this prospectus related to debt investments in our investment portfolio is not intended to approximate a return on your investment in us and does not take into account other aspects of our business, including our operating and other expenses, or other costs incurred by you in connection with your investment in us.

Organization

        Main Street Capital Corporation ("MSCC") is a principal investment firm primarily focused on providing customized debt and equity financing to lower middle market ("LMM") companies and debt capital to middle market ("Middle Market") companies. The portfolio investments of MSCC and its consolidated subsidiaries are typically made to support management buyouts, recapitalizations, growth financings, refinancings and acquisitions of companies that operate in a variety of industry sectors. MSCC seeks to partner with entrepreneurs, business owners and management teams and generally provides "one stop" financing alternatives within its LMM portfolio. MSCC and its consolidated subsidiaries invest primarily in secured debt investments, equity investments, warrants and other securities of LMM companies based in the United States and in secured debt investments of Middle Market companies generally headquartered in the United States.

        MSCC was formed in March 2007 to operate as an internally managed business development company ("BDC") under the Investment Company Act of 1940, as amended (the "1940 Act"). MSCC wholly owns several investment funds, including Main Street Mezzanine Fund, LP ("MSMF"), Main Street Capital II, LP ("MSC II") and Main Street Capital III, LP ("MSC III" and, collectively with MSMF and MSC II, the "Funds"), and each of their general partners. The Funds are each licensed as a Small Business Investment Company ("SBIC") by the United States Small Business Administration ("SBA"). Because MSCC is internally managed, all of the executive officers and other employees are employed by MSCC. Therefore, MSCC does not pay any external investment advisory fees, but instead directly incurs the operating costs associated with employing investment and portfolio management professionals.

        MSC Adviser I, LLC (the "External Investment Manager") was formed in November 2013 as a wholly owned subsidiary of MSCC to provide investment management and other services to parties other than MSCC and its subsidiaries or their portfolio companies ("External Parties") and receives fee income for such services. MSCC has been granted no-action relief by the Securities and Exchange Commission ("SEC") to allow the External Investment Manager to register as a registered investment adviser under the Investment Advisers Act of 1940, as amended. Since the External Investment Manager conducts all of its investment management activities for External Parties, it is accounted for as a portfolio investment of MSCC and is not included as a consolidated subsidiary of MSCC in MSCC's consolidated financial statements.

        MSCC has elected to be treated for U.S. federal income tax purposes as a regulated investment company ("RIC") under Subchapter M of the Internal Revenue Code of 1986, as amended (the

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"Code"). As a result, MSCC generally will not pay corporate-level U.S. federal income taxes on any net ordinary taxable income or capital gains that it distributes to its stockholders.

        MSCC has certain direct and indirect wholly owned subsidiaries that have elected to be taxable entities (the "Taxable Subsidiaries"). The primary purpose of the Taxable Subsidiaries is to permit MSCC to hold equity investments in portfolio companies which are "pass-through" entities for tax purposes.

        Unless otherwise noted or the context otherwise indicates, the terms "we," "us," "our," the "Company" and "Main Street" refer to MSCC and its consolidated subsidiaries, which include the Funds and the Taxable Subsidiaries.

        The following diagram depicts our organizational structure:

GRAPHIC


*
Other Holding Companies includes the Taxable Subsidiaries and other entities formed for operational purposes. Each of these companies is directly or indirectly wholly owned by MSCC.

**
The External Investment Manager is accounted for as a portfolio investment at fair value, as opposed to a consolidated subsidiary, and is indirectly wholly owned by MSCC.

Overview

        Our principal investment objective is to maximize our portfolio's total return by generating current income from our debt investments and capital appreciation from our equity and equity-related investments, including warrants, convertible securities and other rights to acquire equity securities in a portfolio company. Our LMM companies generally have annual revenues between $10 million and $150 million, and our LMM portfolio investments generally range in size from $5 million to $50 million. Our Middle Market investments are made in businesses that are generally larger in size than our LMM portfolio companies, with annual revenues typically between $150 million and $1.5 billion, and our Middle Market investments generally range in size from $3 million to $20 million. Our private loan ("Private Loan") portfolio investments are primarily debt securities in privately held companies which have been originated through strategic relationships with other investment funds on a collaborative basis. Private Loan investments are typically similar in size, structure, terms and conditions to investments we hold in our LMM portfolio and Middle Market portfolio.

        We seek to fill the financing gap for LMM businesses, which, historically, have had limited access to financing from commercial banks and other traditional sources. The underserved nature of the LMM creates the opportunity for us to meet the financing needs of LMM companies while also negotiating favorable transaction terms and equity participations. Our ability to invest across a company's capital structure, from secured loans to equity securities, allows us to offer portfolio companies a comprehensive suite of financing options, or a "one stop" financing solution. Providing customized,

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"one stop" financing solutions is important to LMM portfolio companies. We generally seek to partner directly with entrepreneurs, management teams and business owners in making our investments. Our LMM portfolio debt investments are generally secured by a first lien on the assets of the portfolio company and typically have a term of between five and seven years from the original investment date.

        Our Middle Market portfolio investments primarily consist of direct investments in or secondary purchases of interest-bearing debt securities in privately held companies that are generally larger in size than the companies included in our LMM portfolio. Our Middle Market portfolio debt investments are generally secured by either a first or second priority lien on the assets of the portfolio company and typically have an expected duration of between three and seven years from the original investment date.

        Our Private Loan portfolio investments are primarily debt securities in privately held companies which have been originated through strategic relationships with other investment funds on a collaborative basis, and are often referred to in the debt markets as "club deals." Private Loan investments are typically similar in size, structure, terms and conditions to investments we hold in our LMM portfolio and Middle Market portfolio. Our Private Loan portfolio debt investments are generally secured by either a first or second priority lien on the assets of the portfolio company and typically have a term of between three and seven years from the original investment date.

        Our other portfolio ("Other Portfolio") investments primarily consist of investments which are not consistent with the typical profiles for our LMM, Middle Market or Private Loan portfolio investments, including investments which may be managed by third parties. In our Other Portfolio, we may incur indirect fees and expenses in connection with investments managed by third parties, such as investments in other investment companies or private funds.

        Our external asset management business is conducted through the External Investment Manager. The External Investment Manager earns management fees based on the assets of the funds under management and may earn incentive fees, or a carried interest, based on the performance of the funds managed. We have entered into an agreement with the External Investment Manager to share employees in connection with its asset management business generally, and specifically for its relationship with HMS Income Fund, Inc. ("HMS Income"). Through this agreement, we share employees with the External Investment Manager, including their related infrastructure, business relationships, management expertise and capital raising capabilities.

        Our portfolio investments are generally made through MSCC and the Funds. MSCC and the Funds share the same investment strategies and criteria, although they are subject to different regulatory regimes (see "Business—Regulation" in our most recently filed Annual Report on Form 10-K, as well as in subsequent filings with the SEC). An investor's return in MSCC will depend, in part, on the Funds' investment returns as they are wholly owned subsidiaries of MSCC.

        The level of new portfolio investment activity will fluctuate from period to period based upon our view of the current economic fundamentals, our ability to identify new investment opportunities that meet our investment criteria, and our ability to consummate the identified opportunities. The level of new investment activity, and associated interest and fee income, will directly impact future investment income. In addition, the level of dividends paid by portfolio companies and the portion of our portfolio debt investments on non-accrual status will directly impact future investment income. While we intend to grow our portfolio and our investment income over the long term, our growth and our operating results may be more limited during depressed economic periods. However, we intend to appropriately manage our cost structure and liquidity position based on applicable economic conditions and our investment outlook. The level of realized gains or losses and unrealized appreciation or depreciation on our investments will also fluctuate depending upon portfolio activity, economic conditions and the performance of our individual portfolio companies. The changes in realized gains and losses and unrealized appreciation or depreciation could have a material impact on our operating results.

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        Because we are internally managed, we do not pay any external investment advisory fees, but instead directly incur the operating costs associated with employing investment and portfolio management professionals. We believe that our internally managed structure provides us with a beneficial operating expense structure when compared to other publicly traded and privately held investment firms which are externally managed, and our internally managed structure allows us the opportunity to leverage our non-interest operating expenses as we grow our Investment Portfolio.

        During May 2012, we entered into an investment sub-advisory agreement with HMS Adviser, LP ("HMS Adviser"), which is the investment advisor to HMS Income, a non-listed BDC, to provide certain investment advisory services to HMS Adviser. In December 2013, after obtaining required no-action relief from the SEC to allow us to own a registered investment adviser, we assigned the sub-advisory agreement to the External Investment Manager since the fees received from such arrangement could otherwise have negative consequences on our ability to meet the source-of-income requirement necessary for us to maintain our RIC tax treatment. Under the investment sub-advisory agreement, the External Investment Manager is entitled to 50% of the base management fee and the incentive fees earned by HMS Adviser under its advisory agreement with HMS Income.

        During April 2014, we received an exemptive order from the SEC permitting co-investments by us and HMS Income in certain negotiated transactions where co-investing would otherwise be prohibited under the 1940 Act. We have made, and in the future intend to continue to make, such co-investments with HMS Income in accordance with the conditions of the order. The order requires, among other things, that we and the External Investment Manager consider whether each such investment opportunity is appropriate for HMS Income and, if it is appropriate, to propose an allocation of the investment opportunity between us and HMS Income. Because the External Investment Manager may receive performance-based fee compensation from HMS Income, this may provide it an incentive to allocate opportunities to HMS Income instead of us. However, both we and the External Investment Manager have policies and procedures in place to manage this conflict.

        You should be aware that investments in our portfolio companies carry a number of risks including, but not limited to, investing in companies which may have limited operating histories and financial resources and other risks common to investing in below investment grade debt and equity investments in private, smaller companies. Please see "Risk Factors—Risks Related to Our Investments" in our most recently filed Annual Report on Form 10-K, as well as in subsequent filings with the SEC, for a more complete discussion of the risks involved with investing in our portfolio companies.

        Our principal executive offices are located at 1300 Post Oak Boulevard, 8th Floor, Houston, Texas 77056, and our telephone number is (713) 350-6000. We maintain a website at http://www.mainstcapital.com. Information contained on our website is not incorporated by reference into this prospectus, and you should not consider that information to be part of this prospectus.

Risks Associated with Our Business

        Our business is subject to numerous risks, as described in the section titled "Risk Factors" in the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings in the documents that are incorporated by reference into this prospectus, including the section titled "Risk Factors" included in our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC.

Dividend Reinvestment and Direct Stock Purchase Plan

        We have adopted a dividend reinvestment and direct stock purchase plan (the "Plan"). The Plan primarily consists of a dividend reinvestment feature and a direct stock purchase feature. The direct stock purchase feature of the Plan is designed to provide new investors and existing holders of our

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common stock with a convenient and economical method to purchase shares of our common stock and is described in more detail in a separate prospectus supplement. The dividend reinvestment feature of the Plan, or the dividend reinvestment plan, provides for the reinvestment of dividends on behalf of our registered stockholders who hold their shares with American Stock Transfer & Trust Company, LLC, the plan administrator and our transfer agent and registrar, or certain brokerage firms that have elected to participate in our dividend reinvestment plan, unless a stockholder has elected to receive dividends in cash. For more information, see "Dividend Reinvestment and Direct Stock Purchase Plan."

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The Offering

        We may offer, from time to time, up to $1,500,000,000 of our securities, either individually or in combination, from time to time under this prospectus, together with the applicable prospectus supplement and any related free writing prospectus, at prices and on terms to be determined at the time of any offering. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices, and other important terms of the securities. The applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update, or change information contained in this prospectus or in documents we have incorporated by reference.

        Our securities may be offered directly to one or more purchasers by us or through agents designated from time to time by us, or to or through underwriters or dealers. The prospectus supplement relating to the offering will disclose the terms of the offering, including the name or names of any agents or underwriters involved in the sale of our securities by us, the purchase price, and any fee, commission or discount arrangement between us and our agents or underwriters or among our underwriters or the basis upon which such amount may be calculated. See "Plan of Distribution."

        Set forth below is additional information regarding the offering of our securities:

Use of proceeds

  Except as described in any applicable prospectus supplement or in any free writing prospectus we have authorized for use in connection with a specific offering, we intend to use the net proceeds from any offering pursuant to this prospectus to make investments in accordance with our investment objective and strategies, to pay our operating expenses and other cash obligations, and for general corporate purposes. See "Use of Proceeds."

New York Stock Exchange symbol

 

"MAIN"

Dividends and distributions

 

Our dividends and other distributions, if any, will be determined by our Board of Directors from time to time.

 

Our ability to declare dividends depends on our earnings, our overall financial condition (including our liquidity position), maintenance of our RIC status and such other factors as our Board of Directors may deem relevant from time to time.

 

When we make distributions, we are required to determine the extent to which such distributions are paid out of current or accumulated earnings, recognized capital gains or capital. To the extent there is a return of capital (a distribution of the stockholders' invested capital), investors will be required to reduce their basis in our stock for federal tax purposes. In the future, our distributions may include a return of capital.

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Taxation

 

MSCC has elected to be treated for U.S. federal income tax purposes as a RIC under Subchapter M of the Code. Accordingly, we generally will not pay corporate-level U.S. federal income taxes on any net ordinary income or capital gains that we distribute to our stockholders as dividends. To maintain our qualification as a RIC for U.S. federal income tax purposes, we must meet specified source-of-income and asset diversification requirements and distribute annually at least 90% of our net ordinary income and realized net short-term capital gains in excess of realized net long-term capital losses, if any.

 

Depending on the level of taxable income earned in a tax year, we may choose to carry forward taxable income in excess of current year distributions into the next tax year and pay a 4% U.S. federal excise tax on such income. Any such carryover taxable income must be distributed through a dividend declared on or prior to the later of (i) filing of the U.S. federal income tax return for the applicable fiscal year or (ii) the fifteenth day of the ninth month following the close of the year in which such taxable income was generated. See "Material U.S. Federal Income Tax Considerations."

Dividend reinvestment and direct stock purchase plan

 

We have adopted a dividend reinvestment and direct stock purchase plan, or the Plan. The Plan primarily consists of a dividend reinvestment feature and a direct stock purchase feature. The direct stock purchase feature of the Plan is designed to provide new investors and existing holders of our common stock with a convenient and economical method to purchase shares of our common stock and is described in more detail in a separate prospectus supplement. The dividend reinvestment feature of the Plan, or the dividend reinvestment plan, provides for the reinvestment of dividends on behalf of our registered stockholders who hold their shares with American Stock Transfer & Trust Company, LLC, the plan administrator and our transfer agent and registrar, or certain brokerage firms that have elected to participate in our dividend reinvestment plan, unless a stockholder has elected to receive dividends in cash. As a result, if we declare a cash dividend, our registered stockholders (or stockholders holding shares through participating brokerage firms) who have not properly "opted out" of the dividend reinvestment plan will have their cash dividend automatically reinvested into additional shares of our common stock. See "Dividend Reinvestment and Direct Stock Purchase Plan."

 

Stockholders who receive dividends in the form of stock will be subject to the same federal, state and local tax consequences as stockholders who elect to receive their dividends in cash. See "Dividend Reinvestment and Direct Stock Purchase Plan."

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Trading at a discount

 

Shares of closed-end investment companies frequently trade at a discount to their net asset value. This risk is separate and distinct from the risk that our net asset value per share may decline. We cannot predict whether our shares will trade above, at or below net asset value.

Sales of common stock below net asset value

 

The offering price per share of our common stock, less any underwriting commissions or discounts, will not be less than the net asset value per share of our common stock at the time of the offering, except (i) with the requisite approval of our common stockholders or (ii) under such other circumstances as the Securities and Exchange Commission may permit. In addition, we cannot issue shares of our common stock below net asset value unless our Board of Directors determines that it would be in our and our stockholders' best interests to do so. We did not seek stockholder authorization to issue common stock at a price below net asset value per share at our 2018 annual meeting of stockholders, and we are not seeking such approval at our 2019 annual meeting of stockholders, because our common stock price per share has been trading significantly above the current net asset value per share of our common stock, but we may seek such authorization at future annual meetings or special meetings of stockholders.

 

In addition, we have received stockholder approval to issue warrants, options or rights to subscribe for, convert to, or purchase shares of our common stock at a price per share below the net asset value per share subject to the applicable requirements of the 1940 Act. There is no expiration date on our ability to issue such warrants, options, rights or convertible securities based on this stockholder approval.

 

Sales by us of our common stock at a discount from our net asset value pose potential risks for our existing stockholders whether or not they participate in the offering, as well as for new investors who participate in the offering. See "Sales of Common Stock Below Net Asset Value."

Available Information

 

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). The information we file with the SEC is available free of charge by contacting us at 1300 Post Oak Boulevard, 8th Floor, Houston, TX 77056, by telephone at (713) 350-6000 or on our website at http://www.mainstcapital.com. The SEC also maintains a website that contains reports, proxy statements and other information regarding registrants, including us, that file such information electronically with the SEC. The address of the SEC's website is http://www.sec.gov. Information contained on our website is not incorporated into this prospectus or any related prospectus supplement, and you should not consider information contained on our website to be part of this prospectus or any related prospectus supplement.

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FEES AND EXPENSES

        The following table is intended to assist you in understanding the costs and expenses that an investor in this offering will bear directly or indirectly. We caution you that some of the percentages indicated in the table below are estimates and may vary. Except where the context suggests otherwise, whenever this prospectus contains a reference to fees or expenses paid by "you," "us" or "Main Street," or that "we" will pay fees or expenses, stockholders will indirectly bear such fees or expenses as investors in us.

 
   
 

Stockholder Transaction Expenses:

       

Sales load (as a percentage of offering price)

    —% (1)

Offering expenses (as a percentage of offering price)

    —% (2)

Dividend reinvestment and direct stock purchase plan expenses

    —% (3)

Total stockholder transaction expenses (as a percentage of offering price)

    —% (4)

Annual Expenses of the Company (as a percentage of net assets attributable to common stock):

       

Operating expenses

    2.71% (5)

Interest payments on borrowed funds

    3.40% (6)

Income tax expense

    0.42% (7)

Acquired fund fees and expenses

    0.30% (8)

Total annual expenses

    6.83%  

(1)
In the event that our securities are sold to or through underwriters, a corresponding prospectus supplement will disclose the applicable sales load.

(2)
In the event that we conduct an offering of our securities, a corresponding prospectus supplement will disclose the estimated offering expenses.

(3)
The expenses of administering our dividend reinvestment and direct stock purchase plan are included in operating expenses.

(4)
Total stockholder transaction expenses may include sales load and will be disclosed in a future prospectus supplement, if any.

(5)
Operating expenses in this table represent the estimated expenses of MSCC and its consolidated subsidiaries.

(6)
Interest payments on borrowed funds represent our estimated annual interest payments on borrowed funds based on current debt levels as adjusted for projected increases (but not decreases) in debt levels over the next twelve months.

(7)
Income tax expense relates to the accrual of (a) deferred tax provision (benefit) primarily related to loss carryforwards, timing differences in net unrealized appreciation or depreciation and other temporary book-tax differences from our portfolio investments held in Taxable Subsidiaries and (b) excise, state and other taxes. Deferred taxes are non-cash in nature and may vary significantly from period to period. We are required to include deferred taxes in calculating our annual expenses even though deferred taxes are not currently payable or receivable. Due to the variable nature of deferred tax expense, which can be a large portion of the income tax expense, and the difficulty in providing an estimate for future periods, this income tax expense estimate is based upon the actual amount of income tax expense for the year ended December 31, 2018.

(8)
Acquired fund fees and expenses represent the estimated indirect expense incurred due to investments in other investment companies and private funds.

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Example

        The following example demonstrates the projected dollar amount of total cumulative expenses that would be incurred over various periods with respect to a hypothetical investment in our common stock. In calculating the following expense amounts, we have assumed we would have no additional leverage and that our annual operating expenses would remain at the levels set forth in the table above. In the event that shares to which this prospectus relates are sold to or through underwriters, a corresponding prospectus supplement will restate this example to reflect the applicable sales load.

 
  1 Year   3 Years   5 Years   10 Years  

You would pay the following expenses on a $1,000 investment, assuming a 5.0% annual return

  $ 68   $ 199   $ 326   $ 624  

        The example and the expenses in the table above should not be considered a representation of our future expenses, and actual expenses may be greater or less than those shown. While the example assumes, as required by the SEC, a 5.0% annual return, our performance will vary and may result in a return greater or less than 5.0%. In addition, while the example assumes reinvestment of all dividends at net asset value, participants in our dividend reinvestment plan will receive a number of shares of our common stock, determined by dividing the total dollar amount of the dividend payable to a participant by (i) the market price per share of our common stock at the close of trading on a valuation date determined by our Board of Directors for each dividend in the event that we use newly issued shares to satisfy the share requirements of the dividend reinvestment plan or (ii) the average purchase price of all shares of common stock purchased by the plan administrator in the event that shares are purchased in the open market to satisfy the share requirements of the dividend reinvestment plan, which may be at, above or below net asset value. See "Dividend Reinvestment and Direct Stock Purchase Plan" for additional information regarding our dividend reinvestment plan.

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RISK FACTORS

        Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should carefully consider the risks and uncertainties described in the section titled "Risk Factors" in the applicable prospectus supplement and any related free writing prospectus, and discussed in the section titled "Risk Factors" in our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference, and any free writing prospectus that we may authorize for use in connection with this offering. The risks described in these documents are not the only ones we face. Additional risks and uncertainties that we are unaware of, or that we currently believe are not material, may also become important factors that adversely affect our business. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, reputation, financial condition, results of operations, revenue, and future prospects could be seriously harmed. This could cause our net asset value and the trading price of our securities to decline, resulting in a loss of all or part of your investment. Please also read carefully the section titled "Cautionary Statement Concerning Forward-Looking Statements."

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CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS

        This prospectus, including the documents that we incorporate by reference herein, contains, and any applicable prospectus supplement or free writing prospectus, including the documents we incorporate by reference therein, may contain forward-looking statements, including statements regarding our future financial condition, business strategy, and plans and objectives of management for future operations. All statements other than statements of historical facts, including statements regarding our future results of operations or financial condition, business strategy and plans, and objectives of management for future operations, are forward-looking statements. The forward-looking statements contained or incorporated by reference in this prospectus and any applicable prospectus supplement or free writing prospectus may include statements as to:

        In some cases, you can identify forward-looking statements because they contain words such as "anticipate," "believe," "contemplate," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potential," "predict," "project," "should," "target," "will," or "would" or the negative of these words or other similar terms or expressions, although not all forward-looking statements include these words or expressions. The forward-looking statements contained or incorporated by reference in this prospectus and any applicable prospectus supplement or free writing prospectus involve risks and uncertainties. Our actual results could differ materially from those implied or expressed in the forward-looking statements for any reason, including the factors set forth in "Risk Factors" in our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC, and elsewhere contained or incorporated by reference in this prospectus and any applicable prospectus supplement or free writing prospectus. Other factors that could cause actual results to differ materially include:

        Discussions containing these forward-looking statements may be found in the sections titled "Business," "Risk Factors," and "Management's Discussion and Analysis of Financial Condition and Results of Operations" incorporated by reference from our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC. We discuss in greater detail, and incorporate by reference into this prospectus in their entirety, many of these risks and uncertainties in the sections titled "Risk Factors" in the applicable prospectus supplement, in any free writing prospectus we may authorize for use in connection with a specific offering, and in our most recent Annual Report on Form 10-K, as well as in subsequent filings with the SEC. In addition, statements that we "believe" and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based on information available to us as of the applicable date of this prospectus, free writing prospectus and documents incorporated by reference into this prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely on these statements.

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USE OF PROCEEDS

        Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we intend to use the net proceeds from any offering pursuant to this prospectus to make investments in accordance with our investment objective and strategies, to pay our operating expenses and other cash obligations, and for general corporate purposes. Our ability to achieve our investment objective may be limited to the extent that the net proceeds from an offering, pending full investment, are held in interest-bearing deposits or other short-term instruments. See "Risk Factors—Risks Relating to Our Securities—We may be unable to invest a significant portion of the net proceeds from an offering or from exiting an investment or other capital on acceptable terms, which could harm our financial condition and operating results" in our most recently filed Annual Report on Form 10-K, as well as in subsequent filings with the SEC.

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PRICE RANGE OF COMMON STOCK

        Our common stock is traded on the New York Stock Exchange ("NYSE") under the symbol "MAIN."

        The following table sets forth, for the periods indicated, the range of high and low closing prices of our common stock as reported on the NYSE, and the sales price as a percentage of the net asset value per share of our common stock.

 
   
  Price Range   Premium of
High Closing
Price to
NAV(2)
  Premium of
Low Closing
Price to
NAV(2)
 
 
  NAV(1)   High   Low  

Year ending December 31, 2019

                               

Second Quarter (through April 29, 2019)

    *   $ 39.27   $ 37.49     *     *  

First Quarter                             

    *   $ 39.21   $ 33.99     *     *  

Year ending December 31, 2018

                               

Fourth Quarter

  $ 24.09   $ 39.06   $ 32.58     62%     35%  

Third Quarter

    24.69     40.68     38.05     65%     54%  

Second Quarter

    23.96     38.86     36.76     62%     53%  

First Quarter

    23.67     39.90     35.41     69%     50%  

Year ending December 31, 2017

                               

Fourth Quarter

  $ 23.53   $ 41.55   $ 39.71     77%     69%  

Third Quarter

    23.02     40.40     38.13     75%     66%  

Second Quarter

    22.62     40.39     37.80     79%     67%  

First Quarter

    22.44     38.27     35.39     71%     58%  

(1)
Net asset value per share, or NAV, is determined as of the last day in the relevant quarter and therefore may not reflect the net asset value per share on the date of the high and low closing prices. The net asset values shown are based on outstanding shares at the end of each period. Net asset value has not yet been determined for the first or second quarter of 2019.

(2)
Calculated as the respective high or low share price divided by NAV for such quarter.

        On April 29, 2019, the last sale price of our common stock on the NYSE was $39.27 per share, and there were approximately 365 holders of record of the common stock which did not include stockholders for whom shares are held in "nominee" or "street name." The net asset value per share of our common stock on December 31, 2018 (the last date prior to the date of this prospectus on which we determined our net asset value per share) was $24.09, and the premium of the April 29, 2019 closing price of our common stock was 63% to this net asset value per share.

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

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SENIOR SECURITIES

        Information about our senior securities is shown in the following table as of December 31 for the years indicated in the table, unless otherwise noted. Grant Thornton LLP's report on the senior securities table as of December 31, 2018, is an exhibit to the registration statement of which this prospectus is a part.

Class and Year
  Total Amount Outstanding
Exclusive of
Treasury Securities(1)
  Asset Coverage
per Unit(2)
  Involuntary Liquidating
Preference per Unit(3)
  Average
Market Value
per Unit(4)
 
 
  (dollars in thousands)
   
   
   
 

SBIC Debentures

                         

2009

  $ 65,000     2,995         N/A  

2010

    180,000     2,030         N/A  

2011

    220,000     2,202         N/A  

2012

    225,000     2,763         N/A  

2013

    200,200     2,476         N/A  

2014

    225,000     2,323         N/A  

2015

    225,000     2,368         N/A  

2016

    240,000     2,415         N/A  

2017

    295,800     2,687         N/A  

2018

    345,800     2,455         N/A  

Credit Facility

   
 
   
 
   
 
   
 
 

2010

  $ 39,000     2,030         N/A  

2011

    107,000     2,202         N/A  

2012

    132,000     2,763         N/A  

2013

    237,000     2,476         N/A  

2014

    218,000     2,323         N/A  

2015

    291,000     2,368         N/A  

2016

    343,000     2,415         N/A  

2017

    64,000     2,687         N/A  

2018

    301,000     2,455         N/A  

6.125% Notes

   
 
   
 
   
 
   
 
 

2013

  $ 90,882     2,476       $ 24.35  

2014

    90,823     2,323         24.78  

2015

    90,738     2,368         25.40  

2016

    90,655     2,415         25.76  

2017

    90,655     2,687         25.93  

4.50% Notes Due 2019

   
 
   
 
   
 
   
 
 

2014

  $ 175,000     2,323         N/A  

2015

    175,000     2,368         N/A  

2016

    175,000     2,415         N/A  

2017

    175,000     2,687         N/A  

2018

    175,000     2,455         N/A  

4.50% Notes Due 2022

   
 
   
 
   
 
   
 
 

2017

  $ 185,000     2,687         N/A  

2018

    185,000     2,455         N/A  

(1)
Total amount of each class of senior securities outstanding at the end of the period presented.

(2)
Asset coverage per unit is the ratio of the carrying value of our total consolidated assets, less all liabilities and indebtedness not represented by senior securities, to the aggregate amount of senior securities representing indebtedness. Asset coverage per unit is expressed in terms of dollar amounts per $1,000 of indebtedness.

(3)
The amount to which such class of senior security would be entitled upon the involuntary liquidation of the issuer in preference to any security junior to it. The "—" indicates information that the Securities and Exchange Commission expressly does not require to be disclosed for certain types of senior securities.

(4)
Average market value per unit for our 6.125% Notes represents the average of the daily closing prices as reported on the NYSE during the period presented. Average market value per unit for our SBIC Debentures, Credit Facility, 4.50% Notes due 2019 and 4.50% Notes due 2022 are not applicable because these are not registered for public trading.

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PORTFOLIO COMPANIES

        The following table sets forth certain unaudited information as of December 31, 2018 (dollars in thousands), for the portfolio companies in which we had a debt or equity investment. Other than these investments, our only formal relationships with our portfolio companies are the managerial assistance ancillary to our investments and the board observer or participation rights we may receive. As of December 31, 2018, none of our portfolio company investments constituted five percent or more of our total assets. The following table excludes our investments in marketable securities and idle funds investments.

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Control Investments(5)

 

 

 

 

 

 

                         

                                     

Access Media Holdings, LLC(10)
900 Commerce Drive, Suite 200
Oak Brook, IL 60523

 

July 22, 2015

 

Private Cable Operator

                             

         

10% PIK Secured Debt (Maturity—July 22, 2020)(14)(19)

      $ 23,828   $ 23,828   $ 8,558  

         

Preferred Member Units (9,481,500 units)(27)(30)

    45.0%           9,375     (284 )

         

Member Units (45 units)

    45.0%           1      

                            33,204     8,274  

                                     

ASC Interests, LLC
16500 Westheimer Parkway
Houston, TX 77082

 

August 1, 2013

 

Recreational and Educational Shooting Facility

                             

         

11% Secured Debt (Maturity—July 31, 2020)

        1,650     1,622     1,622  

         

Member Units (1,500 units)

    48.4%           1,500     1,370  

                            3,122     2,992  

                                     

ATS Workholding, LLC(10)
30222 Esperanza
Rancho Santa Margarita, CA 92688

 

March 10, 2014

 

Manufacturer of Machine Cutting Tools and Accessories

                             

         

5% Secured Debt (Maturity—November 16, 2021)

        4,877     4,507     4,390  

         

Preferred Member Units (3,725,862 units)(30)

    41.9%           3,726     3,726  

                            8,233     8,116  

                                     

Bond-Coat, Inc.
11901 West CR 125
Odessa, TX 79765

 

December 28, 2012

 

Casing and Tubing Coating Services

                             

         

12% Secured Debt (Maturity—December 28, 2020)

        11,596     11,367     11,596  

         

Common Stock (57,508 shares)

    41.6%           6,350     9,370  

                            17,717     20,966  

                                     

Brewer Crane Holdings, LLC
12570 Highway 67
Lakeside, CA 92040

 

January 9, 2018

 

Provider of Crane Rental and Operating Services

                             

         

LIBOR Plus 10.00% (Floor 1.00%), Current Coupon 12.35%, Secured Debt (Maturity—January 9, 2023)(9)

        9,548     9,467     9,467  

         

Preferred Member Units (2,950 units)(8)(30)

    80.0%           4,280     4,280  

                            13,747     13,747  

                                     

Café Brazil, LLC
202 West Main Street, Ste. 100
Allen, TX 75013

 

April 20, 2004

 

Casual Restaurant Group

                             

         

Member Units (1,233 units)(8)

    69.0%           1,742     4,780  

                                     

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Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

California Splendor Holdings LLC
7684 Saint Andrews Ave
Suite A San Diego, CA 92154

 

March 30, 2018

 

Processor of Frozen Fruits

                             

         

LIBOR Plus 8.00% (Floor 1.00%), Current Coupon 10.50%, Secured Debt (Maturity—March 30, 2023)(9)

        11,091     10,928     10,928  

         

LIBOR Plus 10.00% (Floor 1.00%), Current Coupon 12.50%, Secured Debt (Maturity—March 30, 2023)(9)

        28,000     27,755     27,755  

         

Preferred Member Units (6,157 units)(8)(30)

    63.4%           10,775     9,745  

                            49,458     48,428  

                                     

CBT Nuggets, LLC
1550 Valley River Drive
Eugene, OR 97401

 

June 1, 2006

 

Produces and Sells IT Training Certification Videos

                             

         

Member Units (416 units)(8)

    40.8%           1,300     61,610  

                                     

Chamberlin Holding LLC
7510 Langtry St
Houston, TX 77040

 

February 26, 2018

 

Roofing and Waterproofing Specialty Contractor

                             

         

LIBOR Plus 10.00% (Floor 1.00%), Current Coupon 12.75%, Secured Debt (Maturity—February 26, 2023)(9)

        20,203     20,028     20,028  

         

Member Units (4,347 units)(8)

    43.5%           11,440     18,940  

         

Member Units (Chamberlin Langfield Real Estate, LLC) (732,160 units)

    45.8%           732     732  

                            32,200     39,700  

                                     

Charps, LLC
453 Tower St NW
Clearbrook, MN 56634

 

February 3, 2017

 

Pipeline Maintenance and Construction

                             

         

12% Secured Debt (Maturity—February 3, 2022)

        11,900     11,805     11,888  

         

Preferred Member Units (1,600 units)(8)(30)

    80.0%           400     2,270  

                            12,205     14,158  

                                     

Clad-Rex Steel, LLC
11500 W. King Street
Franklin Park, IL 60131

 

December 20, 2016

 

Specialty Manufacturer of Vinyl-Clad Metal

                             

         

LIBOR Plus 9.00% (Floor 1.00%), Current Coupon 11.35%, Secured Debt (Maturity—December 20, 2021)(9)

        12,080     12,001     12,080  

         

Member Units (717 units)(8)

    66.0%           7,280     10,610  

         

10% Secured Debt (Clad-Rex Steel RE Investor, LLC) (Maturity—December 20, 2036)

        1,161     1,150     1,161  

         

Member Units (Clad-Rex Steel RE Investor, LLC) (800 units)

    80.0%           210     350  

                            20,641     24,201  

                                     

CMS Minerals Investments
3040 Stout Street
Denver, CO 80205

 

January 30, 2015

 

Oil & Gas Exploration & Production

                             

         

Member Units (CMS Minerals II, LLC) (100 units)(8)

    100.0%           2,707     2,580  

                                     

Copper Trail Fund Investments(12)(13)
621 17th Street
Denver, CO 80293

 

July 17, 2017

 

Investment Partnership

                             

         

LP Interests (CTMH, LP) (Fully diluted 38.8%)

    38.8%           872     872  

         

LP Interests (Copper Trail Energy Fund I, LP) (Fully diluted 30.1%)(8)

    30.1%           3,495     4,170  

                            4,367     5,042  

                                     

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Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Datacom, LLC
100 Enterprise Boulevard
Lafayette, LA 70506

 

May 30, 2014

 

Technology and Telecommunications Provider

                             

         

8% Secured Debt (Maturity—May 30, 2019)(14)

        1,800     1,800     1,690  

         

10.50% PIK Secured Debt (Maturity—May 30, 2019)(14)(19)

        12,511     12,479     9,786  

         

Class A Preferred Member Units(30)

    37.6%           1,294      

         

Class B Preferred Member Units (6,453 units)(30)

    37.6%           6,030      

                            21,603     11,476  

                                     

Digital Products Holdings LLC
900 N. 23rd Street
Saint Louis, MO 63106

 

April 1, 2018

 

Designer and Distributor of Consumer Electronics

                             

         

LIBOR Plus 10.00% (Floor 1.00%), Current Coupon 12.38%, Secured Debt (Maturity—April 1, 2023)(9)

        25,740     25,511     25,511  

         

Preferred Member Units (3,451 shares)(8)(30)

    80.0%           8,466     8,466  

                            33,977     33,977  

                                     

Direct Marketing Solutions, Inc.
8534 NE Alderwood Road
Portland, OR 97220

 

February 13, 2018

 

Provider of Omni-Channel Direct Marketing Services

                             

         

LIBOR Plus 11.00% (Floor 1.00%), Current Coupon 13.38%, Secured Debt (Maturity—February 13, 2023)(9)

        18,017     17,848     17,848  

         

Preferred Stock (8,400 shares)(30)

    80.0%           8,400     14,900  

                            26,248     32,748  

                                     

Gamber-Johnson Holdings, LLC
3001 Borham Ave.
Stevens Point, WI 54481

 

June 24, 2016

 

Manufacturer of Ruggedized Computer Mounting Systems

                             

         

LIBOR Plus 7.50% (Floor 2.00%), Current Coupon 9.85%, Secured Debt (Maturity—June 24, 2021)(9)

        21,486     21,356     21,486  

         

Member Units (8,619 units)(8)

    71.9%           14,844     45,460  

                            36,200     66,946  

                                     

Garreco, LLC
430 Hiram Rd.
Heber Springs, AR 72543

 

July 15, 2013

 

Manufacturer and Supplier of Dental Products

                             

         

LIBOR Plus 8.00% (Floor 1.00%, Ceiling 1.50%), Current Coupon 9.50%, Secured Debt (Maturity—March 31, 2020)(9)

        5,121     5,099     5,099  

         

Member Units (1,200 units)

    32.0%           1,200     2,590  

                            6,299     7,689  

                                     

GRT Rubber Technologies LLC
201 Dana Dr.
Paragould, AR 72450

 

December 19, 2014

 

Manufacturer of Engineered Rubber Products

                             

         

LIBOR Plus 7.00%, Current Coupon 9.35%, Secured Debt (Maturity—December 31, 2023)(9)

        9,740     9,716     9,740  

         

Member Units (5,879 units)(8)

    60.6%           13,065     39,060  

                            22,781     48,800  

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Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Guerdon Modular
Holdings, Inc.
5556 S Federal Way
Boise, ID 83716

 

August 13, 2014

 

Multi-Family and Commercial Modular Construction Company

                             

         

13% Secured Debt (Maturity—March 1, 2019)

        12,588     12,572     12,002  

         

Preferred Stock (404,998 shares)(30)

    24.2%           1,140      

         

Common Stock (212,033 shares)

    1.7%           2,983      

         

Warrants (6,208,877 equivalent shares; Expiration— April 25, 2028; Strike price—$0.01 per unit)(30)

    62.7%                

                            16,695     12,002  

                                     

Gulf Manufacturing, LLC 1221 Indiana St.
Humble, TX 77396

 

August 31, 2007

 

Manufacturer of Specialty Fabricated Industrial Piping Products

                             

         

Member Units (438 units)(8)

    37.0%           2,980     11,690  

                                     

Gulf Publishing Holdings, LLC 2 Greenway Plaza, Suite 1020
Houston, TX 77046

 

April 29, 2016

 

Energy Industry Focused Media and Publishing

                             

         

12.5% Secured Debt (Maturity—April 29, 2021)

        12,666     12,594     12,594  

         

Member Units (3,681 units)

    31.5%           3,681     4,120  

                            16,275     16,714  

                                     

Harborside Holdings, LLC
1300 Post Oak Boulevard, 8th Floor
Houston, TX 77056

 

March 20, 2017

 

Real Estate Holding Company

                             

         

Member units (100 units)

    100.0%           6,306     9,500  

                                     

Harris Preston Fund Investments(12)(13)
2901 Via Fortuna
Austin, TX 78746

 

October 1, 2017

 

Investment Partnership

                             

         

LP Interests (2717 MH, L.P.) (Fully diluted 49.3%)

    49.3%           1,040     1,133  

                                     

Harrison Hydra-Gen, Ltd.
14233 West Road
Houston, TX 77041

 

June 4, 2010

 

Manufacturer of Hydraulic Generators

                             

         

Common Stock (107,456 shares)(8)

    33.6%           718     8,070  

                                     

HW Temps LLC
1308 Belmont St
Brockton, MA 02301

 

July 2, 2015

 

Temporary Staffing Solutions

                             

         

LIBOR Plus 13.00% (Floor 1.00%), Current Coupon 15.35%, Secured Debt (Maturity July 2, 2020)(9)

        9,976     9,938     9,938  

         

Preferred Member Units (3,200 units)(8)(30)

    80.0%           3,942     3,942  

                            13,880     13,880  

                                     

IDX Broker, LLC
100 E Broadway
Eugene, OR 97401

 

November 15, 2013

 

Provider of Marketing and CRM Tools for the Real Estate Industry

                             

         

11.5% Secured Debt (Maturity—November 15, 2020)

        14,350     14,262     14,350  

         

Preferred Member Units (5,607 units)(8)(30)

    97.4%           5,952     13,520  

                            20,214     27,870  

                                     

19


Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Jensen Jewelers of Idaho, LLC
130 Second Avenue North
Twin Falls, ID 83301

 

November 14, 2006

 

Retail Jewelry Store

                             

         

Prime Plus 6.75% (Floor 2.00%), Current Coupon 12.00%, Secured Debt (Maturity—November 14, 2019)(9)

        3,355     3,337     3,355  

         

Member Units (627 units)(8)

    61.4%           811     5,090  

                            4,148     8,445  

                                     

KBK Industries, LLC
East Hwy 96
Rush Center, KS 67575

 

January 23, 2006

 

Manufacturer of Specialty Oilfield and Industrial Products

                             

         

Member Units (325 units)(8)

    25.5%           783     8,610  

                                     

Kickhaefer Manufacturing Company, LLC
1221 S. Park Street
Port Washington, WI 53074

 

October 31, 2018

 

Precision Metal Parts Manufacturing

                             

         

11.5% Secured Debt (Maturity—October 31, 2020)

        1,064     1,045     1,045  

         

11.5% Secured Debt (Maturity—October 31, 2023)

        28,000     27,730     27,730  

         

Member Units (581 units)

    65.5%           12,240     12,240  

         

9.0% Secured Debt (Maturity—October 31, 2048)

        4,006     3,970     3,970  

         

Member Units (KMC RE Investor, LLC) (800 units)

    80.0%           992     992  

                            45,977     45,977  

                                     

Lamb Ventures, LLC
2113 Wells Branch Pkwy, Suite 4000
Austin, TX 78728

 

May 30, 2008

 

Aftermarket Automotive Services Chain

                             

         

11% Secured Debt (Maturity—July 1, 2022)

        8,339     8,306     8,339  

         

Preferred Stock (non-voting)(30)

    100.0%           400     400  

         

Member Units (742 units)

    68.4%           5,273     7,440  

         

9.5% Secured Debt (Lamb's Real Estate Investment I, LLC) (Maturity—March 31, 2027)

        432     428     432  

         

Member Units (Lamb's Real Estate Investment I, LLC) (1,000 units)(8)

    100.0%           625     630  

                            15,032     17,241  

                                     

Market Force Information, LLC
371 Centennial Parkway, Suite 210
Louisville, CO 80027

 

July 28, 2017

 

Provider of Customer Experience Management Services

                             

         

LIBOR Plus 7.00% (Floor 1.00%), Current Coupon 9.74%, Secured Debt (Maturity—July 28, 2022)(9)

        200     200     200  

         

LIBOR Plus 11.00% (Floor 1.00%), Current Coupon 13.74%, Secured Debt (Maturity—July 28, 2022)(9)

        22,800     22,624     22,624  

         

Member Units (657,113 units)

    65.7%           14,700     13,100  

                            37,524     35,924  

                                     

MH Corbin Holding, LLC
8355 Rausch Dr.
Plain City, OH 43064

 

August 31, 2015

 

Manufacturer and Distributor of Traffic Safety Products

                             

         

10% Current / 3% PIK Secured Debt (Maturity—August 31, 2020)(14)(19)

        12,263     12,121     11,733  

         

Preferred Member Units (4,000 shares)(30)

    80.0%           6,000     1,000  

                            18,121     12,733  

                                     

20


Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Mid-Columbia Lumber Products, LLC
710 "C" Street
Culver, OR 97734

 

December 18, 2006

 

Manufacturer of Finger-Jointed Lumber Products

                             

         

10% Secured Debt (Maturity—January 15, 2020)

        1,750     1,746     1,746  

         

12% Secured Debt (Maturity—January 15, 2020)

        3,900     3,880     3,880  

         

Member Units (7,874 units)

    59.5%           3,001     3,860  

         

9.5% Secured Debt (Mid-Columbia Real Estate, LLC) (Maturity—May 13, 2025)

        746     746     746  

         

Member Units (Mid-Columbia Real Estate, LLC) (500 units)(8)

    100.0%           790     1,470  

                            10,163     11,702  

                                     

MSC Adviser I, LLC(16)
1300 Post Oak Boulevard, 8th Floor
Houston, TX 77056

 

November 22, 2013

 

Third Party Investment Advisory Services

                             

         

Member Units (Fully diluted 100.0%)(8)

    100.0%               65,748  

                                     

Mystic Logistics Holdings, LLC
2187 New London Tpke
South Glastonbury, CT 06073

 

August 18, 2014

 

Logistics and Distribution Services Provider for Large Volume Mailers

                             

         

12% Secured Debt (Maturity—August 15, 2019)

        7,536     7,506     7,506  

         

Common Stock (5,873 shares)

    63.5%           2,720     210  

                            10,226     7,716  

                                     

NAPCO Precast, LLC
6949 Low Bid Lane
San Antonio, TX 78250

 

January 31, 2008

 

Precast Concrete Manufacturing

                             

         

LIBOR Plus 8.50%, Current Coupon 11.24%, Secured Debt (Maturity—May 31, 2019)

        11,475     11,464     11,475  

         

Member Units (2,955 units)(8)

    44.5%           2,975     13,990  

                            14,439     25,465  

                                     

NexRev LLC
601 Development Drive
Plano, TX 75074

 

February 28, 2018

 

Provider of Energy Efficiency Products & Services

                             

         

11% Secured Debt (Maturity—February 28, 2023)

        17,440     17,288     17,288  

         

Preferred Member Units (86,400,000 units)(8)(30)

    80.0%           6,880     7,890  

                            24,168     25,178  

                                     

NRI Clinical Research, LLC
2010 Wilshire Blvd
Los Angeles, CA 90057

 

September 8, 2011

 

Clinical Research Service Provider

                             

         

14% Secured Debt (Maturity—June 8, 2022)

        6,685     6,545     6,685  

         

Warrants (251,723 equivalent units; Expiration—June 8, 2027; Strike price—$0.01 per unit)

    12.0%           252     660  

         

Member Units (1,454,167 units)

    23.9%           765     2,478  

                            7,562     9,823  

                                     

NRP Jones, LLC
210 Philadelphia St
LaPorte, IN 46350

 

December 22, 2011

 

Manufacturer of Hoses, Fittings and Assemblies

                             

         

12% Secured Debt (Maturity—March 20, 2023)

        6,376     6,376     6,376  

         

Member Units (65,962 units)

    46.4%           3,717     5,960  

                            10,093     12,336  

                                     

21


Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

NuStep, LLC
5111 Venture Drive
Ann Arbor, MI 48108

 

January 31, 2017

 

Designer, Manufacturer and Distributor of Fitness Equipment

                             

         

12% Secured Debt (Maturity—January 31, 2022)

        20,600     20,458     20,458  

         

Preferred Member Units (406 units)(30)

    66.9%           10,200     10,200  

                            30,658     30,658  

                                     

OMi Holdings, Inc.
1515 E I-30 Service Road
Royse City, TX 75189

 

April 1, 2008

 

Manufacturer of Overhead Cranes

                             

         

Common Stock (1,500 shares)(8)

    48.0%           1,080     16,020  

                                     

Pegasus Research Group, LLC
4636 E. University Drive
Phoenix, AZ 85034

 

January 6, 2011

 

Provider of Telemarketing and Data Services

                             

         

Member Units (460 units)

    43.7%           1,290     7,680  

                                     

PPL RVs, Inc.
10777 Southwest Freeway
Houston, TX 77074

 

June 10, 2010

 

Recreational Vehicle Dealer

                             

         

LIBOR Plus 7.00% (Floor 0.50%), Current Coupon 9.40%, Secured Debt (Maturity—November 15, 2021)(9)

        15,100     15,006     15,100  

         

Common Stock (1,962 shares)(8)

    52.2%           2,150     10,380  

                            17,156     25,480  

                                     

Principle Environmental, LLC
(d/b/a TruHorizon
Environmental Solutions)
201 W. Ranch Court
Weatherford, TX 76088

 

February 1, 2011

 

Noise Abatement Service Provider

                             

         

13% Secured Debt (Maturity—April 30, 2020)

        7,477     7,398     7,477  

         

Preferred Member Units (19,631 units)(8)(30)

    87.7%           4,600     13,090  

         

Warrants (1,018 equivalent units; Expiration—January 31, 2021; Strike price—$0.01 per unit)

    5.0%           1,200     780  

                            13,198     21,347  

                                     

Quality Lease Service, LLC
23403B NW Zac Lentz Pkwy
Victoria, TX 77905

 

June 8, 2015

 

Provider of Rigsite Accommodation Unit Rentals and Related Services

                             

         

Zero Coupon Secured Debt (Maturity—June 8, 2021)

        7,341     7,341     6,450  

         

Member Units (1,000 units)

    100.0%           4,043     3,809  

                            11,384     10,259  

                                     

River Aggregates, LLC
PO Box 8609
The Woodlands, TX 77387

 

March 30, 2011

 

Processor of Construction Aggregates

                             

         

Zero Coupon Secured Debt (Maturity—June 30, 2018)(17)

        750     750     722  

         

Member Units (1,150 units)

    38.3%           1,150     4,610  

         

Member Units (RA Properties, LLC) (1,500 units)

    50.0%           369     2,930  

                            2,269     8,262  

                                     

22


Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Tedder Industries, LLC
4411 W. Riverbend Ave.
Post Falls, ID 83854

 

August 31, 2018

 

Manufacturer of Firearm Holsters and Accessories

                             

         

12% Secured Debt (Maturity—August 31, 2020)

        480     480     480  

         

12% Secured Debt (Maturity—August 31, 2023)

        16,400     16,246     16,246  

         

Preferred Member Units (440 units)(30)

    78.7%           7,476     7,476  

                            24,202     24,202  

                                     

The MPI Group, LLC
319 North Hills Road
Corbin, KY 40701

 

October 2, 2007

 

Manufacturer of Custom Hollow Metal Doors, Frames and Accessories

                             

         

9% Secured Debt (Maturity—October 2, 2019)

        2,924     2,924     2,582  

         

Series A Preferred Units (2,500 units)(30)

    100.0%           2,500     440  

         

Warrants (1,424 equivalent units; Expiration—July 1, 2024; Strike price—$0.01 per unit)

    59.4%           1,096      

         

Member Units (MPI Real Estate Holdings, LLC) (100 units)(8)

    100.0%           2,300     2,479  

                            8,820     5,501  

                                     

Vision Interests, Inc.
6630 Arroyo Springs St., Ste. 600 Las Vegas, NV 89113

 

June 5, 2007

 

Manufacturer / Installer of Commercial Signage

                             

         

13% Secured Debt (Maturity—December 23, 2018)(17)

        2,153     2,153     2,153  

         

Series A Preferred Stock (3,000,000 shares)(30)

    100.0%           3,000     3,740  

         

Common Stock (1,126,242 shares)

    16.7%           3,706     280  

                            8,859     6,173  

                                     

Ziegler's NYPD, LLC
13901 North 73rd St., #219 Scottsdale, AZ 85260

 

October 1, 2008

 

Casual Restaurant Group

                             

         

6.5% Secured Debt (Maturity—October 1, 2019)

        1,000     998     1,000  

         

12% Secured Debt (Maturity—October 1, 2019)

        425     425     425  

         

14% Secured Debt (Maturity—October 1, 2019)

        2,750     2,750     2,750  

         

Warrants (587 equivalent units; Expiration—October 1, 2019; Strike price—$0.01 per unit)

    4.0%           600      

         

Preferred Member Units (10,072 units)(30)

    100.0%           2,834     1,249  

                            7,607     5,424  

Subtotal Control Investments (68.1% of net assets at fair value)

  $ 750,618   $ 1,004,993  

23


Table of Contents

Portfolio Company(1)(20)
  Investment Date(26)
  Business Description
  Type of Investment(2)(3)(25)
  Percent of
Class
Held(29)

  Principal(4)
  Cost(4)
  Fair Value(18)
 
   

Affiliate Investments(6)

 

 

 

 

 

 

                         

                                     

AFG Capital Group, LLC
900 McDuff Avenue
Grandview, TX 76050

 

November 7, 2014

 

Provider of Rent-to-Own Financing Solutions and Services

                             

         

Warrants (42 equivalent units; Expiration—November 7, 2024; Strike price—$0.01 per unit)

    4.0%         $ 259   $ 950  

         

Preferred Member Units (186 units)(8)(30)

    80.0%           1,200     3,980  

                            1,459     4,930  

                                     

Barfly Ventures, LLC(10)
1 Ionia Avenue SW, Suite
200 Grand Rapids, MI 49503

 

August 31, 2015

 

Casual Restaurant Group

                             

         

12% Secured Debt (Maturity—August 31, 2020)

        10,185     10,039     10,018  

         

Options (3 equivalent units)

    4.2%           607     940  

         

Warrant (1 equivalent unit; Expiration—August 31, 2025; Strike price—$1.00 per unit)

    1.7%           473     410  

                            11,119     11,368  

                                     

BBB Tank Services, LLC
162 Independence Parkway North
Baytown, TX 77520

 

April 8, 2016

 

Maintenance, Repair and Construction Services to the Above-Ground Storage Tank Market

                             

         

LIBOR Plus 11.00% (Floor 1.00%), Current Coupon 13.35%, (Maturity—April 8, 2021)(9)

        4,000     3,833     3,833  

         

Preferred Stock (non-voting)(30)

    11.3%           113     113  

         

Member Units (800,000 units)

    10.0%           800     230