格拉德斯通资本美股招股说明书(2026-06-03版)

Table of Contents $60,000,0007.000% Notes due 2029 We operate as an externally managed, closed-end, non-diversified management investment company and have elected to be treated as a businessdevelopment company (“BDC”) under the Investment Company Act of 1940, as amended (“1940 Act”). For federal income tax purposes, we haveelected to be treated as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”). Ourinvestment objectives are to: (1)achieve and grow current income by investing in debt securities of established lower middle market companies in theU.S. that we believe will provide stable earnings and cash flow to pay expenses, make principal and interest payments on our outstanding indebtednessand make distributions to stockholders that grow over time; and (2)provide our stockholders with long-term capital appreciation in the value of ourassets by investing in equity securities, in connection with our debt investments, that we believe can grow over time to permit us to sell our equityinvestments for capital gains. We are offering $60.0million in aggregate principal amount of 7.000% notes due 2029 (the “Notes”). The Notes will mature on December15,2029. We will pay interest on the Notes on June15 and December15 of each year, beginning on December15, 2026. We may redeem the Notes inwhole or in part at any time or from time to time, at the redemption price set forth under the section titled “Description of the Notes—OptionalRedemption” in this prospectus supplement. In addition, holders of the Notes can require us to repurchase some or all of the Notes at a purchase priceequal to 100% of their principal amount, plus accrued and unpaid interest to, but not including, the repurchase date, upon the occurrence of a Change ofControl Repurchase Event (as defined herein). The Notes will be issued in minimum denominations of $1,000 and integral multiples of $1,000 in excessthereof. The Notes will be our direct unsecured obligations and rank equal in right of payment with all outstanding and future unsecured, unsubordinatedindebtedness issued by us (including our 3.75% Notes due 2027 and 5.875% Convertible Notes due 2030 (collectively, the “Existing Notes”)). Becausethe Notes will not be secured by any of our assets, they will be effectively subordinated to any future secured indebtedness of Gladstone CapitalCorporation (or any indebtedness that is initially unsecured as to which we subsequently grant a security interest) to the extent of the value of the assetssecuring such indebtedness. The Notes will be structurally subordinated to all existing and future indebtedness and other obligations of any of oursubsidiaries (including borrowings under our revolving credit facility with KeyBank National Association) since the Notes will be obligationsexclusively of Gladstone Capital Corporation and not of any of our subsidiaries. The Notes will be senior in right of payment to our common stock, our6.25% Series A Cumulative Redeemable Preferred Stock (“Series A Preferred Stock”) and any additional series of our preferred stock we may issue inthe future. None of our subsidiaries is a guarantor of the Notes and the Notes will not be required to be guaranteed by any subsidiary we may acquire orcreate in the future. We do not intend to list the Notes on any securities exchange or automated dealer quotation system. Investing in the Notes involves a high degree of risk, including the risk of leverage. Before buying any Notes, youshould read the material risks described in the “Supplementary Risk Factors” section beginning on page S-9 of thisprospectus supplement and in the “Risk Factors” section beginning on page 5 of the accompanying prospectus andunder similar headings in the other documents that we file from time to time with the Securities and ExchangeCommission (the “SEC”), which are incorporated by reference into this prospectus supplement and the accompanyingprospectus. The Notes are not deposits or other obligations of a bank and are not insured by the Federal Deposit Insurance Corporation or any othergovernment agency. This prospectus supplement, the accompanying prospectus, any free writing prospectus, and the documents incorporated by reference in thisprospectus supplement and the accompanying prospectus contain important information you should know before investing in the Notes, includinginformation about risks. Please read these documents before you invest and retain them for future reference. Additional information about us, includingour annual, quarterly and current reports, has been filed with the SEC and can be accessed free of charge at its website atwww.sec.gov. This informationis also available free of charge by calling us collect at (703) 287-5893 or on the Investors section of our corporate website located atwww.gladstonecapital.com, which, except for the documents incorporated by reference into this prospectus supplement and the accompanyingpr