Main Street Capital Underwriters Exercise Over-Allotment Option

HOUSTON, Nov. 2 /PRNewswire-FirstCall/ -- Main Street Capital Corporation (Nasdaq: MAIN) ("Main Street") announced today that the underwriters of its previously announced initial public offering have exercised their over-allotment option to purchase an additional 300,000 shares of Main Street common stock at $15.00 per share. With the exercise of the over-allotment option, a total of 4,300,000 shares of common stock were sold in the initial public offering resulting in total outstanding shares of 8,826,726. Upon the closing of the over-allotment option, Main Street will receive approximately $4.2 million in incremental net proceeds from the sale of the additional shares after deducting the associated underwriting discount. Including the incremental net proceeds from exercising the over-allotment option, the total net proceeds from the initial public offering are $60.2 million after deducting underwriting discounts.

Morgan Keegan & Company, Inc. and BB&T Capital Markets, a division of Scott & Stringfellow, Inc., served as joint book-running managers for the initial public offering. SMH Capital Inc. and Ferris, Baker Watts Incorporated served as co-managers for the initial public offering. Investors are advised to carefully consider the investment objectives, risks and charges and expenses of Main Street before investing. The prospectus, dated October 4, 2007 contains this and other information about Main Street and should be read carefully before investing. A copy of the prospectus, dated October 4, 2007 may be obtained from Morgan Keegan & Company, Inc., 50 N. Front Street, 19th Floor, Memphis, Tennessee 38103.

This press release does not constitute an offer to sell or the solicitation of an offer to buy, nor will there be any sale of the common stock referred to in this press release in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of such state or jurisdiction. A registration statement relating to the common stock referred to in this press release was filed with, and has been declared effective by, the Securities and Exchange Commission.

ABOUT MAIN STREET CAPITAL CORPORATION

Main Street (http://www.mainstreethouston.com) is a principal investment firm that provides long-term debt and equity capital to lower middle market companies. Main Street's investments are generally made to support management buyouts, recapitalizations, growth financings and acquisitions of companies that operate in diverse industry sectors and generally have annual revenues ranging from $10 to $100 million. Main Street seeks to partner with entrepreneurs, business owners and management teams and generally provides "one-stop" financing alternatives to its portfolio companies.

FORWARD-LOOKING STATEMENTS

This press release may contain certain forward-looking statements. Any such statements, other than statements of historical fact, are likely to be affected by other unknowable future events and conditions, including elements of the future that are or are not under Main Street's control, and that Main Street may or may not have considered; accordingly, such statements cannot be guarantees or assurances of any aspect of future performance. Actual developments and results are highly likely to vary materially from these estimates and projections of the future. Such statements speak only as of the time when made, and Main Street undertakes no obligation to update any such statement now or in the future.

     Contacts:
     Main Street Capital Corporation
     Todd A. Reppert, President and CFO
     treppert@mainstreethouston.com
     713-350-6000

     Dennard Rupp Gray and Easterly, LLC
     Ken Dennard
     ksdennard@drg-e.com / 713-529-6600
     Augustine Okwu
     gokwu@drg-e.com / 404-532-0086

SOURCE Main Street Capital Corporation

Released November 2, 2007