Fourth Supplemental Indenture between Gladstone Capital Corporation and U.S. Bank National Association, dated as of November 4, 2021

Exhibit 4.1

FOURTH SUPPLEMENTAL INDENTURE

between

GLADSTONE CAPITAL CORPORATION

and

U.S. BANK NATIONAL ASSOCIATION, as Trustee

Dated as of November 4, 2021

THIS FOURTH SUPPLEMENTAL INDENTURE (this “Fourth Supplemental Indenture”), dated as of November 4, 2021, is between Gladstone Capital Corporation, a Maryland corporation (the “Company”), and U.S. Bank National Association, as trustee (the “Trustee”). All capitalized terms used herein shall have the meaning set forth in the Base Indenture (as defined below).

RECITALS OF THE COMPANY

WHEREAS, the Company and the Trustee executed and delivered an Indenture, dated as of November 6, 2018 (the “Base Indenture” and, as supplemented by this Fourth Supplemental Indenture, the “Indenture”), to provide for the issuance by the Company from time to time of the Securities, to be issued in one or more series as provided in the Base Indenture;

WHEREAS, the Company desires to initially issue and sell $50,000,000 aggregate principal amount of the Company’s 3.75% Notes due 2027 (the “Notes”);

WHEREAS, Sections 2.01, 9.01(e) and 9.01(g) of the Base Indenture provide that, without the consent of the Holders of the Securities of any series issued under the Indenture, the Company, when authorized by or pursuant to a Board Resolution, and the Trustee, at any time and from time to time, may enter into one or more indentures supplemental to the Base Indenture to (i) add to, delete from, or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication, and delivery of Securities, as set forth in the Base Indenture and (ii) provide for the issuance of and establish the form and terms and conditions of the Securities of any series as provided in Section 2.01 of the Base Indenture, to establish the form of any certifications required to be furnished pursuant to the terms of the Base Indenture or any series of Securities, or to add to the rights of the holders of any series of Securities;

WHEREAS, the Company desires to establish the form and terms of the Notes and to modify, alter, supplement and change certain provisions of the Base Indenture for the benefit of the Holders of the Notes (except as may be provided in a future supplemental indenture to the Indenture (each, a “Future Supplemental Indenture”)); and

WHEREAS, the Company has duly authorized the execution and delivery of this Fourth Supplemental Indenture to provide for the issuance of the Notes and all acts and things necessary to make this Fourth Supplemental Indenture a valid, binding, and legal obligation of the Company and to constitute a valid agreement of the Company, in accordance with its terms, have been done and performed,

NOW, THEREFORE, for and in consideration of the premises and the purchase of the Notes by the Holders thereof, it is mutually agreed, for the equal and proportionate benefit of all Holders of the Notes, as follows:

ARTICLE I

TERMS OF THE NOTES

Section 1.01. Terms of the Notes. The following terms relating to the Notes are hereby established:

(a) The Notes shall constitute a series of Securities having the title “3.75% Notes due 2027”. The Notes shall bear a CUSIP number of 376535 AD2 and an ISIN number of US376535AD29 and the Notes offered and sold to Institutional “Accredited Investors” under Rule 501(a)(1), (2), (3), (7) or (9) under the Securities Act shall bear a CUSIP number of 376535 AE0 and an ISIN number of US376535AE02.

(b) The aggregate principal amount of the Notes that may be initially authenticated and delivered under the Indenture (except for Notes authenticated and delivered upon registration of, transfer of, or in exchange for, or in lieu of, other Notes pursuant to Sections 2.05, 2.06, 2.07, 3.02(a) and 9.04, of the Base Indenture) shall be $50,000,000. Under a Board Resolution, Officers’ Certificate pursuant to Board Resolutions or a Future Supplemental Indenture, the Company may from time to time, without the consent of the Holders of Notes, issue additional Notes (in any such case, “Additional Notes”) having the same ranking and the same interest rate, maturity and other terms as the Notes; provided that, if such Additional Notes are not fungible with the Notes (or any other tranche of Additional Notes) for U.S. federal income tax purposes, then such Additional Notes shall have different CUSIP numbers from the Notes (and any such other tranche of Additional Notes). Any Additional Notes and the existing Notes shall constitute a single series under the Indenture, and all references to the relevant Notes herein shall include the Additional Notes unless the context otherwise requires.

(c) The entire outstanding principal of the Notes shall be payable on May 1, 2027 unless earlier redeemed or repurchased in accordance with the provisions of the Indenture.

(d) The rate at which the Notes shall bear interest shall be 3.75% per annum. Additional Interest with respect to the Notes shall be payable in accordance with the provisions of and in the amounts set forth in the Registration Rights Agreement. For the avoidance of doubt, any references in the Indenture to “interest” payable with respect to the Notes shall include Additional Interest, if any, payable pursuant to the Registration Rights Agreement, and any Additional Interest that accrues on a Note will be in addition to the stated interest that accrues on such Note. It shall be the obligation of the Company to notify the Trustee of any Additional Interest payable on the Notes pursuant to this Section 1.01(d), no later than 5:00 p.m. prevailing Eastern Time three (3) Business Days prior to the date any such interest is payable hereunder. Such notice shall be given by delivery to the Trustee of an Officers’ Certificate stating (i) the amount of such Additional Interest that is payable and (ii) the date that such Additional Interest begins to accrue, on which the Trustee shall conclusively rely. The Trustee shall have no obligation to (i) determine whether Additional Interest is due with respect to the Notes or (ii) to determine the interest rate applicable to the Notes. Unless and until the Trustee receives such Officers’ Certificate, the Trustee may assume without inquiry that no such Additional Interest is payable and the Trustee shall have no duty to verify the Company’s calculation of Additional Interest.

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(e) The date from which interest shall accrue on the Notes shall be November 4, 2021, or the most recent Interest Payment Date to which interest has been paid or provided for; the Interest Payment Dates for the Notes shall be May 1 and November 1 of each year, commencing May 1, 2022 (provided that, if an Interest Payment Date falls on a day that is not a Business Day, then the applicable interest payment shall be made on the next succeeding Business Day and no additional interest shall accrue as a result of such delayed payment); the initial interest period shall be the period from and including November 4, 2021, to, but excluding, the initial Interest Payment Date, and the subsequent interest periods shall be the periods from and including an Interest Payment Date to, but excluding, the next Interest Payment Date or the Stated Maturity, as the case may be; the interest so payable, and punctually paid or duly provided for, on any Interest Payment Date, shall be paid to the Person in whose name the Note (or one or more Predecessor Securities) is registered at the close of business on the Regular Record Date for such interest, which shall be April 15 or October 15 (whether or not a Business Day), as the case may be, next preceding such Interest Payment Date. Payment of principal of (and premium, if any, on) and any such interest on the Notes shall be made at the office of the Trustee located at 111 Fillmore Avenue, St. Paul, MN 55107, Attention: Gladstone Capital Corporation (3.75% Notes Due 2027) or at such other address as designated by the Trustee, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that, at the option of the Company, payment of interest may be made by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register; provided, further, however, that, at the request of the registered Holder, the Company will pay the principal of (and premium, if any, on) and interest, if any, on the Notes by wire transfer of immediately available funds to an account at a bank in St. Paul, Minnesota, on the date when such amount is due and payable and as further set forth in Section 4.01 of the Indenture; provided, further, however, that, so long as the Notes are registered to Cede & Co., such payment will be made by wire transfer in accordance with the procedures established by The Depository Trust Company and the Trustee. Interest on the Notes shall be computed on the basis of a 360-day year of twelve 30-day months.

(f) The Notes offered and sold to QIBs in reliance on Rule 144A shall be initially issuable in global form (each such Note, a “144A Global Note”) which, along with the Trustee’s certificate of authentication thereon shall be substantially in the form of Exhibit A to this Fourth Supplemental Indenture. The Notes offered and sold to Institutional “Accredited Investors” under Rule 501(a) (1), (2), (3), (7) or (9) under the Securities Act shall be initially issuable in global form (each such Note, a “IAI Global Note” and together with the 144A Global Note, the “Global Notes”) which, along with the Trustee’s certificate of authentication thereon shall be substantially in the form of Exhibit B to this Fourth Supplemental Indenture. Each Global Note shall represent the aggregate principal amount of Outstanding Notes as shall be specified therein and each shall provide that it shall represent the aggregate principal amount of Outstanding Notes from time to time endorsed thereon and that the aggregate principal amount of Outstanding Notes represented thereby may from time to time be reduced or increased, as appropriate, to reflect exchanges and redemptions. Any new Global Note reflecting the amount of any increase or decrease in the aggregate principal amount of Outstanding Notes represented thereby shall be made by the Trustee, in accordance with Section 2.05 of the Base Indenture.

(g) Every Note authenticated and delivered hereunder shall bear a legend in substantially the following form (the “Restricted Securities Legend”) unless and until (1) a Note is exchanged for an Exchange Note or otherwise sold in connection with an effective registration statement, or (2) such Restricted Securities Legend is no longer required in accordance with Section 1.01(i) of this Fourth Supplemental Indenture:

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT.

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THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF (1) REPRESENTS THAT IT IS [A “QUALIFIED INSTITUTIONAL BUYER” (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT (“RULE 144A”))]/[AN INSTITUTIONAL “ACCREDITED INVESTOR” WITHIN THE MEANING OF RULE 501(a)(1), (2), (3), (7) or (9) UNDER THE SECURITIES ACT THAT IS NOT A “QUALIFIED INSTITUTIONAL BUYER” (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT (“RULE 144A”))] AND (2) AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION TERMINATION DATE”) WHICH IS ONE YEAR (OR SUCH OTHER DATE WHEN RESALES OF SECURITIES BY NON-AFFILIATES ARE FIRST PERMITTED UNDER RULE 144(d)) AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF (OR ANY PREDECESSOR OF THIS SECURITY) OR THE DATE OF ANY SUBSEQUENT REOPENING OF THE SECURITIES AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY), ONLY (A) TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A PERSON IT REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (D) TO AN INSTITUTIONAL “ACCREDITED INVESTOR” WITHIN THE MEANING OF RULE 501(a)(1), (2), (3), (7) or (9) UNDER THE SECURITIES ACT THAT IS NOT A QUALIFIED INSTITUTIONAL BUYER AND THAT IS PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF ANOTHER INSTITUTIONAL ACCREDITED INVESTOR, OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND THE SECURITIES LAWS OF ANY OTHER JURISDICTION, INCLUDING ANY STATE OF THE UNITED STATES, SUBJECT TO THE COMPANY’S AND THE TRUSTEE’S RIGHT PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL SATISFACTORY TO EACH OF THEM AND/OR A CERTIFICATE OF TRANSFER OR EXCHANGE IN THE FORM PRESCRIBED IN THE INDENTURE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.

(h) Unless and until a Note is exchanged for an Exchange Note, with respect to any proposed registration of transfer of any Note prior to (x) the date which is one year (or such other date when resales of securities by non-Affiliates are first permitted under Rule 144(d) of the Exchange Act) after the later of the date of the original issue date of the applicable Notes or the date of any subsequent reopening of such Notes and the last date on which the Company or any of the Company’s Affiliates were the owner of such Notes (or any predecessor thereto) or (y) such later date, if any, as may be required by applicable law (the “Resale Restriction Termination Date”), the Holder of such Note and each subsequent Holder thereof shall offer, sell, or otherwise transfer such Note only (i) to the Company or any of the Company’s Subsidiaries, (ii) pursuant to a registration statement which has become effective under the Securities Act, (iii) for so long as such Note is eligible for resale pursuant to Rule 144A, to a Person it reasonably believes is a QIB that purchases for its own account or for the account of a QIB to whom notice is given that the transfer is being made in reliance on Rule 144A, (iv) to an institutional “accredited investor” within the meaning of Rule 501(a)(1), (2), (3), (7) or (9) under the Securities Act that is purchasing for its own account or for the account of such an institutional “accredited investor” or (v) pursuant to any other available exemption from the registration requirements of the Securities Act; in each of the foregoing

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cases subject to any requirements of law that the disposition of its property or the property of such investor account or accounts be at all times within its or their control and in compliance with any applicable state securities laws. The foregoing restrictions on resale will not apply subsequent to the Resale Restriction Termination Date

(i) Upon the transfer or replacement of a Global Note (or beneficial interest therein) not bearing a Restricted Securities Legend (an “Unrestricted Global Note”), the Trustee shall deliver an Unrestricted Global Note (or beneficial interest therein) and upon the transfer or replacement of a definitive Note not bearing a Restricted Securities Legend (an “Unrestricted Definitive Note”), the Trustee shall deliver an Unrestricted Definitive Note. Upon the transfer, exchange, or replacement of a Global Note (or beneficial interest therein) bearing a Restricted Securities Legend (a “Restricted Global Note”), the Trustee shall deliver only a Restricted Global Note (or beneficial interest therein) and upon the transfer, exchange or replacement of a definitive Note bearing a Restricted Securities Legend (a “Restricted Definitive Note”), the Trustee shall deliver only Restricted Definitive Notes unless, in each case, (i)(x) a Note is being transferred pursuant to an effective registration statement, or (y) Notes are being exchanged for Notes that do not bear the Restricted Securities Legend in accordance with the following paragraph, and (ii) there is delivered to the Trustee an Opinion of Counsel satisfactory to it stating that neither such legend nor the related restrictions on transfer are required in order to maintain compliance with the provisions of the Securities Act, upon which opinion the Trustee may conclusively rely. Any Notes sold in a registered offering shall not be required to bear the Restricted Securities Legend.

Upon the Company’s satisfaction that the Restricted Securities Legend shall no longer be required in order to maintain compliance with the Securities Act, beneficial interests in a Restricted Global Note may be automatically exchanged into beneficial interests in an Unrestricted Global Note without any action required by or on behalf of the Holder (the “Automatic Exchange”) at any time on or after the date that is the 366th calendar day after the later of the date of the original issue date of the applicable Notes or the date of any subsequent reopening of such Notes, or in each case, if such day is not a Business Day, on the next succeeding Business Day.

Upon the Company’s satisfaction that the Restricted Securities Legend shall no longer be required in order to maintain compliance with the Securities Act, the Company may cause the Restricted Securities Legend to be removed by (i) providing the Depositary an instruction letter for the Depositary’s mandatory exchange process (or any successor notice, form, or action required pursuant to the Depositary’s applicable procedures) to the extent required; (ii) providing written notice to the Trustee (x) instructing the Trustee to take any actions as may be necessary so that the Restricted Securities Legend set forth on the Global Notes shall be deemed removed from the Global Notes in accordance with the terms and conditions of the Notes and the Indenture, without further action on the part of Holders and (y) instructing the Trustee to take any actions as may be necessary so that the restricted CUSIP number for the Notes shall be removed from the Global Notes and replaced with an unrestricted CUSIP number; and (iii) on or prior to the effective date of the Automatic Exchange (such date, the “Automatic Exchange Date”), deliver to the Trustee for authentication one or more Unrestricted Global Notes, duly executed by the Company, in an aggregate principal amount equal to the aggregate principal amount of Restricted Global Notes to be exchanged into such Unrestricted Global Notes. The Restricted Global Note from which beneficial interests are transferred pursuant to an Automatic Exchange shall be cancelled following the Automatic Exchange.

Any definitive Note delivered in exchange for an interest in a Global Note pursuant to Sections 2.05 and 2.11 of the Base Indenture shall bear the applicable legend regarding transfer restrictions applicable thereto set forth in this Section 1.01 of this Fourth Supplemental Indenture unless (i) the Global Note is an Unrestricted Global Note, or (ii) there is delivered to the Trustee an Opinion of Counsel satisfactory to it stating that neither such legend nor the related restrictions on transfer are required in order to maintain compliance with the provisions of the Securities Act, upon which opinion the Trustee may conclusively rely.

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The Trustee shall have no obligation or duty to monitor, determine or inquire as to compliance with any restrictions on transfer imposed under this Indenture or under applicable law with respect to any transfer of any interest in any Note other than to require delivery of such certificates and other documentation or evidence as are expressly required by, and to do so if and when expressly required by, the terms of this Fourth Supplemental Indenture and any Notes, and to examine the same to determine substantial compliance as to form with the express requirements hereof.

All certifications, certificates and Opinions of Counsel required to be submitted to the Security Registrar pursuant to this Section 1.01 of this Fourth Supplemental Indenture to effect a registration of transfer or exchange may be submitted by facsimile.

(j) Upon the occurrence of the Exchange Offer, the Company shall issue and, upon receipt of the Company Order for the authentication and delivery of such Exchange Notes, the Trustee shall authenticate and deliver, one or more Unrestricted Global Notes in an aggregate principal amount equal to the principal amount of the Restricted Global Notes tendered for acceptance in accordance with the Exchange Offer and accepted for exchange in the Exchange Offer and one or more Unrestricted Definitive Notes in an aggregate principal amount equal to the principal amount of the Restricted Definitive Notes tendered for acceptance in accordance with the Exchange Offer and accepted for exchange in the Exchange Offer. Concurrently with the issuance of such Unrestricted Global Notes and/or Unrestricted Definitive Notes, the Security Registrar for the Notes shall cause the aggregate principal amount of the Restricted Global Notes and/or Restricted Definitive Notes to be reduced accordingly, and the Company shall execute and the Trustee shall authenticate Unrestricted Global Notes and/or Unrestricted Definitive Notes in the appropriate principal amount.

(k) The depositary for such Global Notes (the “Depository”) shall be DTC. The Security Registrar with respect to the Global Notes shall be the Trustee.

(l) The Notes shall be redeemable pursuant to Section 3.01 of the Base Indenture and as follows:

(i) The Notes shall be redeemable in whole or in part at any time or from time to time, at the option of the Company, at a Redemption Price (as determined by the Company) equal to the greater of the following amounts, plus, in each case, accrued and unpaid interest to, but excluding, the Redemption Date:

(a) 100% of the outstanding principal amount of the Notes to be redeemed, or

(b) the sum of the present values of the remaining scheduled payments of principal and interest (exclusive of accrued and unpaid interest to the Redemption Date) on the Notes to be redeemed, discounted to the Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) using the applicable Treasury Rate plus 50 basis points;

provided, however, that if the Company redeems any Notes on or after February 1, 2027, the Redemption Price for the Notes will be equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the Redemption Date.

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For purposes of calculating the Redemption Price in connection with the redemption of the Notes, on any Redemption Date, the following terms have the meanings set forth below:

“Comparable Treasury Issue” means the United States Treasury security selected by the Reference Treasury Dealer as having a maturity comparable to the remaining term of the Notes to be redeemed that would be utilized, at the time of selection and in accordance with customary financing practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Notes being redeemed.

“Comparable Treasury Price” means (1) the average of the Reference Treasury Dealer Quotations for the Redemption Date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the Quotation Agent obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Quotation Agent” means a Reference Treasury Dealer selected by the Company.

“Reference Treasury Dealer” means each of any four primary U.S. government securities dealers selected by the Company.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Quotation Agent by such Reference Treasury Dealer at 3:30 p.m. New York City time on the third business day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per annum equal to the semi-annual equivalent yield-to-maturity of the Comparable Treasury Issue (computed as of the third business day immediately preceding the redemption), assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date. The Redemption Price and the Treasury Rate will be determined by the Company.

All determinations made by any Reference Treasury Dealer, including the Quotation Agent, with respect to determining the Redemption Price will be final and binding absent manifest error.

(ii) Notice of redemption shall be given in writing and mailed, first-class postage prepaid or by overnight courier guaranteeing next-day delivery, to each Holder of the Notes to be redeemed, not less than thirty (30) nor more than sixty (60) days prior to the Redemption Date, at the Holder’s address appearing in the Security Register. All notices of redemption shall contain the information set forth in Section 3.02(a) of the Base Indenture.

(iii) Any exercise of the Company’s option to redeem the Notes shall be done in compliance with the Indenture and the Investment Company Act, to the extent applicable.

(iv) If the Company elects to redeem only a portion of the Notes, the Trustee or, with respect to the Global Notes, the Depository shall determine the method for selecting the particular Notes to be redeemed, in accordance with Section 3.02(b) of the Base Indenture and the Investment Company Act.

(v) Unless the Company defaults in payment of the Redemption Price, on and after the Redemption Date, interest shall cease to accrue on the Notes called for redemption hereunder.

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(m) The Notes shall not be subject to any sinking fund pursuant to Section 3.04 of the Base Indenture.

(n) The Notes shall be issuable in denominations of $2,000 and integral multiples of $1,000 in excess thereof.

(o) Holders of the Notes shall not have the option to have the Notes repaid prior to the Stated Maturity other than in accordance with Article 15 of the Indenture.

ARTICLE II

DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

Section 2.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Article One of the Base Indenture shall be amended by adding the following defined terms to Section 1.01 in appropriate alphabetical sequence, as follows:

“‘Act’, when used with respect to any Holder of a Note, has the meaning specified in Section 8.01 of the Indenture.”

“‘Additional Interest’ means all additional interest then owing pursuant to Section 6 of the Registration Rights Agreement. Unless the context indicates otherwise, all references to “interest” in this Indenture or the Notes shall be deemed to include any Additional Interest to the extent then applicable.

“‘Affiliate’ of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, “control” when used with respect to any specified Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms “controlling” and “controlled” have meanings correlative to the foregoing.”

“‘Below Investment Grade Rating Event’ means the Notes are downgraded below Investment Grade by the Rating Agency on any date from the date of the public notice of an arrangement that results in a Change of Control until the end of the 60-day period following public notice of the occurrence of a Change of Control (which period shall be extended so long as the rating of the Notes is under publicly announced consideration for possible downgrade by the Rating Agency); provided that a Below Investment Grade Rating Event otherwise arising by virtue of a particular reduction in rating shall not be deemed to have occurred in respect of a particular Change of Control (and thus shall not be deemed a Below Investment Grade Rating Event for purposes of the definition of Change of Control Repurchase Event hereunder) if the Rating Agency does not announce or publicly confirm or inform the Trustee in writing at its request (acting at the direction of holders of a majority in principal amount of the Notes) that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the applicable Change of Control (whether or not the applicable Change of Control shall have occurred at the time of the Below Investment Grade Rating Event).”

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“‘Change of Control’ means the occurrence of any of the following:

(1) the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation) in one or a series of related transactions, of all or substantially all of the assets of the Company and its Controlled Subsidiaries taken as a whole to any “person” or “group” (as those terms are used in Section 13(d)(3) of the Exchange Act), other than to any Permitted Holders; provided that, for the avoidance of doubt, a pledge of assets pursuant to any secured debt instrument of the Company or its Controlled Subsidiaries shall not be deemed to be any such sale, lease, transfer, conveyance or disposition;

(2) the consummation of any transaction (including, without limitation, any merger or consolidation) the result of which is that any “person” or “group” (as those terms are used in Section 13(d)(3) of the Exchange Act) (other than any Permitted Holders) becomes the “beneficial owner” (as defined in Rules 13d-3 and 13d-5 under the Exchange Act), directly or indirectly, of more than 50% of the outstanding Voting Stock of the Company, measured by voting power rather than number of shares; or

(3) the approval by the Company’s stockholders of any plan or proposal relating to the liquidation or dissolution of the Company.”

“‘Change of Control Repurchase Event’ means the occurrence of a Change of Control and a Below Investment Grade Rating Event.”

“‘Company Order’ means, a written request or order signed in the name of the Company by the Chief Executive Officer, President or a Vice President of the Company, and by the Chief Financial Officer, Chief Operating Officer, Chief Accounting Officer, Secretary or an Assistant Secretary of the Company, and delivered to the Trustee.”

“‘Controlled Subsidiary’ means any subsidiary of the Company, 50% or more of the outstanding equity interests of which are owned by the Company and its direct or indirect subsidiaries and of which the Company possesses, directly or indirectly, the power to direct or cause the direction of the management or policies, whether through the ownership of voting equity interests, by agreement or otherwise.”

“‘Default’ means any event that is, or after notice or passage of time or both would be, an Event of Default.”

“‘DTC’ means The Depository Trust Company, New York, New York.”

“‘Egan-Jones’ means Egan-Jones Ratings Company or any successor thereto.”

“‘Exchange Act’ means the United States Securities Exchange Act of 1934, as amended, and the rules, regulations and interpretations promulgated thereunder, to the extent applicable, and any statute successor thereto.”

“‘Exchange Notes’ means, the Notes issued in the Exchange Offer, and which Exchange Notes shall contain terms identical in all material respect to the Initial Notes, except that the Exchange Notes will not bear the Restricted Securities Legend and will be issued and exchanged for the Notes pursuant to the Registration Rights Agreement and this Indenture.”

“‘Exchange Offer’ means an offer that may be made by the Company pursuant to the Registration Rights Agreement to exchange Initial Notes for the Exchange Notes.”

“‘GAAP’ means generally accepted accounting principles in the United States set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants, the opinions and pronouncements of the Public Company Accounting Oversight Board and the statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as have been approved by a significant segment of the accounting profession in the United States, which are in effect from time to time.”

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“‘Holder” means the Person or Persons in whose name or names a particular Note is registered on the Security Register kept for that purpose in accordance with the terms of this Indenture.

“‘Initial Notes’ means the Notes issued on the date hereof that contain the Restricted Securities Legend.”

“‘Investment Company Act’ means the United States Investment Company Act of 1940, as amended, and the rules, regulations and interpretations promulgated thereunder, to the extent applicable, and any statute successor thereto.”

“‘Investment Grade’ means a rating of BBB- or better by Egan-Jones (or its equivalent under any successor rating categories of Egan-Jones) (or, if such Rating Agency ceases to rate the Notes for reasons outside of the Company’s control, the equivalent investment grade credit rating from any Rating Agency selected by the Company as a replacement Rating Agency).”

“‘Maturity’, when used with respect to any Note, means the date on which the principal of such Note or an installment of principal becomes due and payable as therein or herein provided, whether at the Stated Maturity or by declaration of acceleration, notice of redemption, notice of option to elect repayment, notice of exchange or conversion or otherwise.”

“‘Permitted Holders’ means (i) the Company, (ii) one or more Controlled Subsidiaries or (iii) Gladstone Management Corporation, any affiliate of Gladstone Management Corporation or any entity that is managed or advised by Gladstone Management Corporation or any of their affiliates.”

“‘QIB’ means any “qualified institutional buyer” as such term is defined in Rule 144A under the Securities Act.”

“‘Rating Agency’ means:

(1) Egan-Jones; and

(2) if Egan-Jones ceases to rate the Notes or fails to make a rating of the Notes publicly available for reasons outside of the Company’s control, a “nationally recognized statistical rating organization” as defined in Section (3)(a)(62) of the Exchange Act selected by the Company as a replacement agency for Egan-Jones.”

“‘Redemption Date’, when used with respect to any Note to be redeemed, in whole or in part, means the date fixed for such redemption by or pursuant to this Indenture.”

“‘Redemption Price’, when used with respect to any Note to be redeemed, means the price at which it is to be redeemed pursuant to this Indenture.”

“Registration Rights Agreement” means that certain registration rights agreement, dated as of November 4, 2021, by and between the Company and Raymond James & Associates, Inc.

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“‘Regular Record Date’ for the interest payable on any Interest Payment Date on the Notes means the date specified for that purpose as contemplated by Section 1.01(e) of this Fourth Supplemental Indenture.”

“‘Securities Act’ means the U.S. Securities Act of 1933, as amended, and the rules and regulations of the Commission promulgated thereunder, as amended.”

“‘Special Record Date’ for the payment of any Defaulted Interest on the Notes means a date fixed by the Trustee pursuant to Section 2.03 of the Base Indenture.”

“‘Stated Maturity’ means, when used with respect to any Note or any installment of principal thereof or interest thereon, the date specified in such Note as the fixed date on which the principal of such Note or such installment of principal or interest is due and payable.”

“‘Trustee’ means U.S. Bank National Association, and, subject to the provisions of Article Seven of the Base Indenture, its successors and assigns under the Indenture.”

“‘Voting Stock’ as applied to stock of any person, means shares, interests, participations or other equivalents in the equity interest (however designated) in such person having ordinary voting power for the election of a majority of the directors (or the equivalent) of such person, other than shares, interests, participations or other equivalents having such power only by reason of the occurrence of a contingency.”

Section 2.02. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Article One of the Base Indenture shall be amended by replacing the definitions of “Business Day”, “Corporate Trust Office” and “Officers’ Certificate” in Section 1.01 with the following:

“‘Business Day’, when used with respect to any particular location referred to in this Indenture or in the Notes, means each Monday, Tuesday, Wednesday, Thursday and Friday that is not a day on which banking institutions in The City of New York, Nashville, Tennessee, the city in which the Corporate Trust Office is located or that particular location are authorized or obligated by law or executive order to close.”

“‘Corporate Trust Office’ means the principal office of the Trustee at which at any time its corporate trust business shall be administered, which office at the date hereof for purposes of presentment of Notes for transfer, exchange or surrender only is located at 111 Fillmore Avenue East, Mailcode: EP-MN-WS2N, St. Paul, MN 55107, Attention: Gladstone Capital Corporation, and for all other purposes is located at 333 Commerce Street, Suite 800, Nashville, TN 37201, Attention: Gladstone Capital Corporation, or such other address as the Trustee may designate from time to time by notice to the Holders and the Company, or the principal corporate trust office of any successor Trustee (or such other address as such successor Trustee may designate from time to time by notice to the Holders and the Company).”

“‘Officers’ Certificate’ means a certificate signed by the Chairman of the Board, the Chief Executive Officer, the Chief Financial Officer, the Chief Operating Officer (or, in each case, any permitted designee of such Person as may be identified as such in a writing delivered to the Trustee from time to time), and by any President, the Treasurer, or the Secretary of the Company and delivered to the Trustee.”

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Section 2.03. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, the first paragraph of Section 1.01 of the Base Indenture shall be amended and restated as follows:

The terms defined in this Section (except as in this Indenture or any indenture supplemental hereto otherwise expressly provided or unless the context otherwise requires) for all purposes of this Indenture and of any indenture supplemental hereto shall have the respective meanings specified in this Section and shall include the plural as well as the singular. All other terms used in this Indenture that are defined in the Trust Indenture Act of 1939, as amended, or that are by reference in such Act defined in the Securities Act of 1933, as amended (except as herein or any indenture supplemental hereto otherwise expressly provided or unless the context otherwise requires), shall have the meanings assigned to such terms in said Trust Indenture Act and in said Securities Act as in force at the date of the execution of this instrument. Any reference to “execute”, “executed”, “sign”, “signed”, “signature” or any other like term hereunder shall include execution by electronic signature (including, without limitation, any .pdf file, .jpeg file, or any other electronic or image file, or any “electronic signature” as defined under the U.S. Electronic Signatures in Global and National Commerce Act (“E-SIGN”) or the New York Electronic Signatures and Records Act (“ESRA”), which includes any electronic signature provided using Orbit, Adobe Fill & Sign, Adobe Sign, DocuSign, or any other similar platform identified by the Company and reasonably available at no undue burden or expense to the Trustee), except to the extent the Trustee requests otherwise. Any such electronic signatures shall be valid, effective and legally binding as if such electronic signatures were handwritten signatures and shall be deemed to have been duly and validly delivered for all purposes hereunder.

ARTICLE III

REDEMPTION OF NOTES

Section 3.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 3.02(b) of the Base Indenture shall be amended by replacing the text thereof with the following:

“If less than all the Notes are to be redeemed, the particular Notes to be redeemed shall be selected by the Trustee, or by the Depository in the case of Global Notes, in compliance with the requirements of DTC, from the Outstanding Notes not previously called for redemption, or if the Notes are not held through DTC, or DTC prescribed no method of selection, by such method as the Trustee shall deem fair and appropriate and subject to and otherwise in accordance with the procedures of the applicable Depository; provided, however, that no such partial redemption shall reduce the portion of the principal amount of a Note not redeemed to less than the minimum authorized denomination for the Notes.”

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ARTICLE IV

COVENANTS

Section 4.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 4.01 of the Base Indenture shall be amended and restated as follows:

“The Company will duly and punctually pay or cause to be paid the principal of (and premium, if any) and interest on the Notes at the time and place and in the manner provided herein and established with respect to such Notes. Payments of principal on the Notes may be made at the time provided herein and established with respect to such Notes by U.S. dollar check drawn on and mailed to the address of the Holder entitled thereto as such address shall appear in the Security Register. Alternatively, at the request of the registered Holder, the Company will pay the principal of (and premium, if any, on) and interest, if any, on the Notes by wire transfer of immediately available funds to an account at a bank in St. Paul, Minnesota, on the date when such amount is due and payable. To request payment by wire transfer, the registered Holder must give the Security Registrar and the Trustee appropriate wire transfer instructions at least 15 Business Days before the requested payment is due. In the case of any interest payment due on an Interest Payment Date, the instructions must be given by the person who is the registered Holder on the Regular Record Date. Any wire instructions, once properly given, will remain in effect unless and until new instructions are given in accordance with this Section.”

Section 4.02. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Article Four of the Base Indenture shall be amended by adding the following new Sections 4.06, 4.07 and 4.08 thereto, each as set forth below:

“Section 4.06. Section 18(a)(1)(A) of the Investment Company Act.

The Company hereby agrees that for the period of time during which Notes are Outstanding, the Company will not violate Section 18(a)(1)(A) as modified by Section 61(a)(2) of the Investment Company Act or any successor provisions, whether or not the Company continues to be subject to such provisions of the Investment Company Act.”

“Section 4.07. Section 18(a)(1)(B) of the Investment Company Act.

The Company will not violate Section 18(a)(1)(B) as modified by Section 61(a)(2) of the Investment Company Act or any successor provisions thereto giving effect to any no-action relief granted by the Commission to another business development company and upon which the Company may reasonably rely (or to the Company if the Company determines to seek such similar no-action or other relief) permitting the business development company to declare any cash dividend or distribution notwithstanding the prohibition contained in Section 18(a)(1)(B) as modified by Section 61(a)(2) of the Investment Company Act in order to maintain such business development company’s status as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended.”

“Section 4.08. Commission Reports and Reports to Holders.

If, at any time, the Company is not subject to the reporting requirements of Sections 13 or 15(d) of the Exchange Act to file any periodic reports with the Commission, the Company agrees to furnish to Holders of the Notes and the Trustee for the period of time during which the Notes are Outstanding: (i) within 90 days after the end of the each fiscal year of the Company, audited annual consolidated financial statements of the Company and (ii) within 45 days after the end of each fiscal quarter of the Company (other than the Company’s fourth fiscal quarter), unaudited interim consolidated financial statements of the Company. All such financial statements shall be prepared, in all material respects, in accordance with GAAP.”

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ARTICLE V

REMEDIES

Section 5.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 6.01(a) of the Base Indenture shall be amended and restated as follows:

“(a) Whenever used herein with respect to the Notes, “Event of Default” means any one or more of the following events that has occurred and is continuing:

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and the continuance of any such decree or order for relief or any such other decree or order unstayed and in effect for a period of 60 consecutive days; or

Section 5.02. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 6.01(b) of the Base Indenture shall be amended and restated as follows:

“(b) If an Event of Default (other than an Event of Default under Section 6.01(a)(4) or Section 6.01(a)(5)) with respect to the Notes at the time Outstanding occurs and is continuing, then and in every such case, the Trustee or the Holders of not less than 25% in principal amount of the Outstanding Notes may (and the Trustee shall at the request of such Holders) declare the principal of all the Notes to be due and payable immediately, by a notice in writing to the Company (and to the Trustee if given by the Holders), and upon any such declaration such principal or specified portion thereof shall become immediately due and payable, but does not entitle any Holder to any redemption payout or redemption premium. If an Event of Default under Section 6.01(a)(4) or Section 6.01(a)(5) occurs, the entire principal amount of all the Notes will automatically become due and immediately payable.”

Section 5.03. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 6.02(a) of the Base Indenture shall be amended and restated as follows:

“(a) The Company covenants that (i) in case it shall default in the payment of any installment of interest on any of the Notes, or in any payment required by any sinking or analogous fund established with respect to that series, as and when the same shall have become due and payable, and such default shall have continued for a period of 30 days, or (ii) in case it shall default in the payment of the principal of (or premium, if any, on) any of the Notes when the same shall have become due and payable, whether upon maturity of the Notes or upon redemption or upon declaration or otherwise then, upon demand of the Trustee, the Company will pay to the Trustee, for the benefit of the holders of the Notes, the whole amount that then shall have been become due and payable on all such Notes for principal (and premium, if any) or interest, or both, as the case may be, with interest upon the overdue principal (and premium, if any) and (to the extent that payment of such interest is enforceable under applicable law) upon overdue installments of interest at the rate per annum expressed in the Notes; and, in addition thereto, such further amount as shall be sufficient to cover the costs and expenses of collection, and the amount payable to the Trustee under Section 7.06.”

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Section 5.04. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, the first paragraph of Section 6.04 of the Base Indenture shall be amended and restated as follows:

“No holder of any Note shall have any right by virtue or by availing of any provision of this Indenture to institute any suit, action or proceeding in equity or at law upon or under or with respect to this Indenture or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless (i) such holder previously shall have given to the Trustee written notice of an Event of Default and of the continuance thereof with respect to the Notes specifying such Event of Default, as hereinbefore provided; (ii) the holders of not less than 25% in aggregate principal amount of the Notes then Outstanding shall have made written request upon the Trustee to institute such action, suit or proceeding in its own name as Trustee hereunder; (iii) such holder or holders shall have offered to the Trustee such reasonable indemnity as it may require against the costs, expenses and liabilities to be incurred therein or thereby; (iv) the Trustee for 60 days after its receipt of such notice, request and offer of indemnity, shall have failed to institute any such action, suit or proceeding and (v) during such 60 day period, the holders of a majority in principal amount of the Notes do not give the Trustee a direction inconsistent with the request.”

ARTICLE VI

CONCERNING THE SECURITYHOLDERS

Section 6.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, the second paragraph of Section 8.01 of the Base Indenture shall be amended by replacing the text thereof with the following:

“If the Company shall solicit from the Holders of the Notes any request, demand, authorization, direction, notice, consent, waiver or other act (each, an “Act”), the Company may, at its option, in or pursuant to a Board Resolution, fix in advance a record date for the determination of Holders of the Notes entitled to give such Act, but the Company shall have no obligation to do so. Such record date shall be the record date specified in or pursuant to such Board Resolution, which date shall be a date not earlier than the date 30 days prior to the first solicitation of Holders of the Notes generally in connection therewith and not later than the date such solicitation is completed. If such a record date is fixed, such Act may be given before or after such record date, but only the Holders of the Notes of record at the close of business on such record date shall be deemed to be Holders for the purposes of determining whether Holders of the Notes of the requisite proportion of Outstanding Notes have authorized or agreed or consented to such Act, and for that purpose the Outstanding Notes shall be computed as of such record date; provided that no such authorization, agreement or consent by the Holders of the Notes on such record date shall be deemed effective unless it shall become effective pursuant to the provisions of this Indenture not later than eleven months after the record date.”

ARTICLE VII

SUPPLEMENTAL INDENTURES

Section 7.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 9.01 of the Base Indenture shall be amended by replacing the text thereof with the following:

“Without the consent of any Holders of the Notes, the Company, when authorized by or pursuant to a Board Resolution, and the Trustee, at any time and from time to time, may enter into one or more indentures supplemental hereto, in form reasonably satisfactory to the Trustee, for any of the following purposes:

(a) to evidence the succession of another Person to the Company and the assumption by any such successor of the covenants of the Company herein and in the Securities contained; or

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(b) to add to the covenants of the Company for the benefit of the Holders of all or any series of Securities (and if such covenants are to be for the benefit of less than all series of Securities, stating that such covenants are expressly being included solely for the benefit of such series) or to surrender any right or power herein conferred upon the Company; or

(c) to add any additional Events of Default for the benefit of the Holders of all or any series of Securities (and if such Events of Default are to be for the benefit of less than all series of Securities, stating that such Events of Default are expressly being included solely for the benefit of such series); provided, however, that in respect of any such additional Events of Default such supplemental indenture may provide for a particular period of grace after default (which period may be shorter or longer than that allowed in the case of other defaults) or may provide for an immediate enforcement upon such default or may limit the remedies available to the Trustee upon such default or may limit the right of the Holders of a majority in aggregate principal amount of that or those series of Securities to which such additional Events of Default apply to waive such default; or

(d) to change or eliminate any of the provisions of this Indenture; provided that any such change or elimination shall become effective only when there is no Security Outstanding of any series created prior to the execution of such supplemental indenture that is entitled to the benefit of such provision; or

(e) to secure the Securities; or

(f) to establish the form or terms of Securities of any series as permitted by Section 2.01, including the provisions and procedures relating to Securities convertible into or exchangeable for any securities of any Person (including the Company); or

(g) to evidence and provide for the acceptance of appointment hereunder by a successor Trustee with respect to the Securities of one or more series and to add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee; or

(h) to cure any ambiguity, to correct or supplement any provision herein which may be inconsistent with any other provision herein, or to make any other provisions with respect to matters or questions arising under this Indenture; provided that such action shall not adversely affect the interests of the Holders of Securities of any series in any material respect; or

(i) to supplement any of the provisions of this Indenture to such extent as shall be necessary to permit or facilitate the defeasance and discharge of any series of Securities pursuant to Sections 11.01, 14.02 and 14.03; provided that any such action shall not adversely affect the interests of the Holders of Securities of such series or any other series of Securities in any material respect.

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Any supplemental indenture authorized by the provisions of this Section may be executed by the Company and the Trustee without the consent of the holders of any of the Securities at the time Outstanding, notwithstanding any of the provisions of Section 9.02.”

Section 7.02. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 9.02 of the Base Indenture shall be amended by replacing the text thereof with the following:

“With the consent of the Holders of not less than a majority in aggregate principal amount of all Outstanding Notes affected by such supplemental indenture, by Act of said Holders delivered to the Company and the Trustee, the Company, when authorized by or pursuant to a Board Resolution, and the Trustee may enter into an indenture or indentures supplemental hereto for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture that affects the Notes or of modifying in any manner the rights of the Holders of the Notes under this Indenture; provided, however, that no such supplemental indenture shall, without the consent of the Holder of each Outstanding Note:

(a) change the Stated Maturity of the principal of (or premium, if any) or any installment of principal of or interest on, any Note; or reduce the principal amount thereof or the rate of interest (or change the manner of calculating the rate of interest thereon), or any premium payable upon the redemption thereof, or reduce the portion of the principal of a Note that would be due and payable upon a declaration of acceleration of the Maturity thereof pursuant to Section 6.01(b), or upon the redemption thereof or the amount thereof provable in bankruptcy pursuant to Section 6.02(c), or adversely affect any right of repayment at the option of the Holder, or change any place of payment where, or the currency in which, any Note or any premium or interest thereon is payable, or impair the right to institute suit for the enforcement of any such payment on or after the Stated Maturity thereof (or, in the case of redemption or repayment at the option of the Holder, on or after the Redemption Date), or

(b) reduce the percentage in principal amount of the Outstanding Notes, the consent of whose Holders is required for any such supplemental indenture, or the consent of whose Holders is required for any waiver with respect to such series (of compliance with certain provisions of this Indenture or certain defaults hereunder and their consequences) provided for in this Indenture, or reduce any requirements of Section 8.01 for quorum or voting, or

(c) modify any of the provisions of this Section or Section 6.01(c) except to increase any such percentage or to provide that certain other provisions of this Indenture cannot be modified or waived without the consent of the Holder of each Outstanding Note affected thereby; provided, however, that this clause shall not be deemed to require the consent of any Holder of a Note with respect to changes in the references to “the Trustee” and concomitant changes in this Section, or the deletion of this proviso, in accordance with the requirements of Sections 7.11 and 9.01(h).

It shall not be necessary for any Act of Holders under this Section to approve the particular form of any proposed supplemental indenture, but it shall be sufficient if such Act shall approve the substance thereof.

A supplemental indenture that changes or eliminates any covenant or other provision of this Indenture which has expressly been included solely for the benefit of one or more particular series of Securities, or that modifies the rights of the Holders of Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Securities of any other series.

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The Company may, but shall not be obligated to, fix a record date for the purpose of determining the Persons entitled to consent to any indenture supplemental hereto. If a record date is fixed, the Holders on such record date, or their duly designated proxies, and only such Persons, shall be entitled to consent to such supplemental indenture, whether or not such Holders remain Holders after such record date; provided, that unless such consent shall have become effective by virtue of the requisite percentage having been obtained prior to the date that is 90 days after such record date, any such consent previously given shall automatically and without further action by any Holder be cancelled and of no further effect.”

ARTICLE VIII

SUCCESSOR ENTITY

Section 8.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 10.01 of the Base Indenture shall be amended by replacing the text thereof with the following:

“The Company shall not consolidate with or merge with or into any other entity or convey or transfer all or substantially all of its properties and assets to any Person, unless:

(1) either the Company shall be the continuing entity, or the entity (if other than the Company) formed by such consolidation or into which the Company is merged or the Person which acquires by conveyance or transfer the properties and assets of the Company substantially as an entirety shall expressly assume, by an indenture supplemental hereto, executed and delivered to the Trustee, in form satisfactory to the Trustee, the due and punctual payment of the principal of (and premium, if any) and interest, if any, on all the Notes and the performance of every covenant of this Indenture on the part of the Company to be performed or observed;

(2) immediately after giving effect to such transaction, no Default or Event of Default shall have occurred and be continuing; and

(3) the Company has delivered to the Trustee an Officers’ Certificate and an Opinion of Counsel each stating that such consolidation, merger, conveyance or transfer and such supplemental indenture comply with this Article and that all conditions precedent herein provided for relating to such transaction have been complied with.”

ARTICLE IX

SATISFACTION AND DISCHARGE

Section 9.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 11.01 of the Base Indenture shall be amended by replacing the text thereof with the following:

“Except as set forth below, this Indenture shall upon Company Request cease to be of further effect with respect to any Notes specified in such Company Request (except as to any surviving rights of registration of transfer or exchange of Notes expressly provided for herein or pursuant hereto, any surviving rights of tender for repayment at the option of the Holders), and the Trustee, upon receipt of a Company Order, and at the expense of the Company, shall execute proper instruments acknowledging satisfaction and discharge of this Indenture as to such series when

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(1) either

(A) all Notes theretofore authenticated and delivered (other than (i) Notes which have been destroyed, lost or stolen and which have been replaced or paid as provided in Section 2.07 and (ii) Notes for whose payment money has theretofore been deposited in trust with the Trustee or any paying agent or segregated and held in trust by the Company and thereafter repaid to the Company or discharged from such trust, as provided in Sections 4.03, 11.03 and 11.05) have been delivered to the Trustee for cancellation; or

(B) all Notes

(i) have become due and payable, or

(ii) will become due and payable at their Stated Maturity within one year, or

(iii) if redeemable at the option of the Company, are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption by the Trustee in the name, and at the expense, of the Company,

and the Company, in the case of (i), (ii) or (iii) above, has irrevocably deposited or caused to be deposited with the Trustee as trust funds in trust for such purpose, solely for the benefit of the Holders, an amount in the Currency in which the Notes are payable, sufficient to pay and discharge the entire indebtedness on such Notes not theretofore delivered to the Trustee for cancellation, for principal (and premium, if any) and interest, if any, to the date of such deposit (in the case of Notes which have become due and payable) or to the Stated Maturity or Redemption Date, as the case may be;

(2) the Company has irrevocably paid or caused to be irrevocably paid all other sums payable hereunder by the Company; and

(3) the Company has delivered to the Trustee an Officers’ Certificate and an Opinion of Counsel, each stating that all conditions precedent herein provided for relating to the satisfaction and discharge of this Indenture as to such series have been complied with.

Notwithstanding the satisfaction and discharge of this Indenture, the obligations of the Company to the Trustee and any predecessor Trustee under Section 7.06, the obligations of the Company to any Authenticating Agent under Section 2.10 and, if money shall have been deposited with the Trustee pursuant to subclause (B) of clause (1) of this Section, the obligations of the Trustee under Sections 11.03 and 11.04 shall survive any termination of this Indenture.”

Section 9.02. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, Section 11.02 of the Base Indenture shall be amended by replacing the text thereof with the following:

“[Intentionally omitted.]”

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ARTICLE X

DEFEASANCE AND COVENANT DEFEASANCE

Section 10.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, the Base Indenture shall be amended by adding a new Article 14 as follows:

“ARTICLE 14

DEFEASANCE AND COVENANT DEFEASANCE

Section 14.01. Company’s Option to Effect Defeasance or Covenant Defeasance.

The Company may at its option by Board Resolution, at any time, with respect to the Notes, elect to have either Section 14.02 (if applicable) or Section 14.03 (if applicable) be applied to such Outstanding Notes upon compliance with the conditions set forth below in this Article.

Section 14.02. Defeasance and Discharge.

Upon the Company’s exercise of the above option applicable to this Section with respect to the Notes, the Company shall be deemed to have been discharged from its obligations with respect to such Outstanding Notes on and after the date the conditions set forth in Section 14.04 are satisfied (hereinafter, “defeasance”). For this purpose, such defeasance means that the Company shall be deemed to have paid and discharged the entire indebtedness represented by such Outstanding Notes, which shall thereafter be deemed to be “Outstanding” only for the purposes of Section 14.05 and the other Sections of this Indenture referred to in clauses (A) and (B) of this Section, and to have satisfied all its other obligations under the Notes and this Indenture insofar as such Notes are concerned (and the Trustee, at the expense of the Company, shall execute proper instruments acknowledging the same), except for the following which shall survive until otherwise terminated or discharged hereunder: (A) the rights of Holders of such Outstanding Notes receive, solely from the trust fund described in Section 14.04 and as more fully set forth in such Section, payments in respect of the principal of (and premium, if any) and interest, if any, on the Notes when such payments are due, (B) the Company’s obligations with respect to such Notes under Sections 2.05, 2.07, 4.02 and 4.03, (C) the rights, powers, trusts, duties and immunities of the Trustee hereunder and (D) this Article. Subject to compliance with this Article Fourteen, the Company may exercise its option under this Section notwithstanding the prior exercise of its option under Section 14.03 with respect to such Notes. Following a defeasance, payment of such Notes may not be accelerated because of an Event of Default.

Section 14.03. Covenant Defeasance.

Upon the Company’ s exercise of the above option applicable to this Section with respect to any Notes, the Company shall be released from its obligations under Sections 4.06, 4.07 and 4.08 on and after the date the conditions set forth in Section 14.04 are satisfied (hereinafter, “covenant defeasance”), and such Notes shall thereafter be deemed to be not “Outstanding” for the purposes of any direction, waiver, consent or declaration or Act of Holders (and the consequences of any thereof) in connection such covenant, but shall continue to be deemed “Outstanding” for all other purposes hereunder. For this purpose, such covenant defeasance means that, with respect to such Outstanding Notes, the Company may omit to comply with and shall have no liability in respect of any term, condition or limitation set forth in any such Section or such other covenant, whether directly or indirectly, by reason of any reference elsewhere herein to any such Section or such other covenant or by reason of reference in any such Section or such other covenant to any other provision herein or in any other document and such omission to comply shall not constitute a Default or an Event of Default under Section 6.01(a)(3) or otherwise, as the case may be, but, except as specified above, the remainder of this Indenture and such

Notes shall be unaffected thereby. Following a covenant defeasance, payment of such Notes may not be accelerated because of an Event of Default solely by reference to such Sections specified above in this Section 14.03.

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Section 14.04. Conditions to Defeasance or Covenant Defeasance.

The following shall be the conditions to application of either Section 14.02 or Section 14.03 to any Outstanding Notes:

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ARTICLE XI

OFFER TO REPURCHASE UPON A CHANGE OF CONTROL REPURCHASE EVENT

Section 11.01. Except as may be provided in a Future Supplemental Indenture, for the benefit of the Holders of the Notes but no other series of Securities under the Indenture, whether now or hereafter issued and Outstanding, the Base Indenture shall be amended by adding a new Article 15 as follows:

“ARTICLE 15

CHANGE OF CONTROL REPURCHASE EVENT

Section 15.01. Change of Control.

If a Change of Control Repurchase Event occurs, unless the Company shall have exercised its right to redeem the Notes in full, the Company shall make an offer to each Holder of Notes to repurchase all or any part (in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof) of that Holder’s Notes at a repurchase price in cash equal to 100% of the aggregate principal amount of Notes repurchased plus any accrued and unpaid interest on the Notes repurchased to, but excluding, the date of repurchase. Within 30 days following any Change of Control Repurchase Event or, at the Company’s option, prior to any Change of Control, but after the public announcement of the Change of Control, the Company shall mail a notice to each Holder describing the transaction or transactions that constitute or may constitute the Change of Control Repurchase Event and offering to repurchase Notes on the payment date specified in the notice, which date shall be no earlier than 30 days and no later than 60 days from the date such notice is mailed. The notice shall, if mailed prior to the date of consummation of the Change of Control, state that the offer to purchase is conditioned on the Change of Control Repurchase Event occurring on or prior to the payment date specified in the notice. The Company shall comply with the requirements of Rule 14e-1 promulgated under the Exchange Act and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of the Notes as a result of a Change of Control Repurchase Event. To the extent that the provisions of any securities laws or regulations conflict with this Section 15.01, the Company shall comply with the applicable securities laws and regulations and shall not be deemed to have breached its obligations under this Section 15.01 by virtue of such conflict.

On the Change of Control Repurchase Event payment date, subject to extension if necessary to comply with the provisions of the Investment Company Act, the Company will, to the extent lawful:

(a) accept for payment all Notes or portions of Notes properly tendered pursuant to its offer;

(b) deposit with the paying agent an amount equal to the aggregate purchase price in respect of all Notes or portions of Notes properly tendered; and

(c) deliver or cause to be delivered to the Trustee the Notes properly accepted, together with an Officers’ Certificate stating the aggregate principal amount of Notes being purchased by the Company.

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The paying agent will promptly remit to each holder of Notes properly tendered the purchase price for the Notes, and the Trustee will promptly authenticate and mail (or cause to be transferred by book-entry) to each holder a new Note equal in principal amount to any unpurchased portion of any Notes surrendered; provided that each new Note will be in a minimum principal amount of $2,000 or an integral multiple of $1,000 in excess thereof.

If any Repayment Date upon a Change of Control Repurchase Event falls on a day that is not a Business Day, then the required payment will be made on the next succeeding Business Day and no additional interest will accrue as a result of such delayed payment.

The Company will not be required to make an offer to repurchase the Notes upon a Change of Control Repurchase Event if a third party makes an offer in respect of the Notes in the manner, at the times and otherwise in compliance with the requirements for an offer made by the Company and such third party purchases all Notes properly tendered and not withdrawn under its offer.”

ARTICLE XII

THE TRUSTEE

Section 12.01 Neither the Trustee nor any paying agent shall be responsible for determining whether any Change of Control or Below Investment Grade Rating Event has occurred and whether any Change of Control offer with respect to the Notes is required.

ARTICLE XIII

MISCELLANEOUS

Section 13.01. This Fourth Supplemental Indenture and the Notes shall be governed by and construed in accordance with the law of the State of New York. This Fourth Supplemental Indenture is subject to the provisions of the Trust Indenture Act that are required to be part of the Indenture and shall, to the extent applicable, be governed by such provisions.

Section 13.02. In case any provision in this Fourth Supplemental Indenture or in the Notes shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

Section 13.03. This Fourth Supplemental Indenture may be executed in any number of counterparts, each of which so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same Fourth Supplemental Indenture. The exchange of copies of this Fourth Supplemental Indenture and of signature pages by facsimile, ..pdf transmission, email or other electronic means shall constitute effective execution and delivery of this Fourth Supplemental Indenture for all purposes. Signatures of the parties hereto transmitted by facsimile, .pdf transmission, email or other electronic means shall be deemed to be their original signatures for all purposes. The words “execution,” “signed,” “signature,” “delivery,” and words of like import in or relating to this Fourth Supplemental Indenture or any document to be signed in connection with this Fourth Supplemental Indenture shall be deemed to include electronic signatures (including, without limitation, any .pdf file, .jpeg file or any other electronic or image file, or any other “electronic signature” as defined under E-SIGN or ESRA, including Orbit, Adobe Fill & Sign, Adobe Sign, DocuSign, or any other similar platform identified by the Company and reasonably available at no undue burden or expense to the Trustee), deliveries or the keeping of records in electronic form, each of which shall be of the same legal effect, validity or enforceability as a manually executed signature, physical delivery thereof or the use of a paper-based recordkeeping system, as the case may be, and the parties hereto consent to conduct the transactions contemplated hereunder by electronic means.

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Section 13.04. The Base Indenture, as supplemented and amended by this Fourth Supplemental Indenture, is in all respects ratified and confirmed, and the Base Indenture and this Fourth Supplemental Indenture shall be read, taken and construed as one and the same instrument with respect to the Notes. All provisions included in this Fourth Supplemental Indenture supersede any conflicting provisions included in the Base Indenture with respect to the Notes, unless not permitted by law. The Trustee accepts the trusts created by the Base Indenture, as supplemented by this Fourth Supplemental Indenture, and agrees to perform the same upon the terms and conditions of the Base Indenture, as supplemented by this Fourth Supplemental Indenture.

Section 13.05. The provisions of this Fourth Supplemental Indenture shall become effective as of the date hereof.

Section 13.06. Notwithstanding anything else to the contrary herein, the terms and provisions of this Fourth Supplemental Indenture shall apply only to the Notes and shall not apply to any other series of Securities under the Indenture, and this Fourth Supplemental Indenture shall not and does not otherwise affect, modify, alter, supplement or change the terms and provisions of any other series of Securities under the Indenture, whether now or hereafter issued and Outstanding.

Section 13.07. The recitals contained herein and in the Notes, except the Trustee’s certificate of authentication, shall be taken as the statements of the Company, and the Trustee assumes no responsibility for their correctness. The Trustee makes no representations as to the validity or sufficiency of this Fourth Supplemental Indenture, the Notes or any Additional Notes, except that the Trustee represents that it is duly authorized to execute and deliver this Fourth Supplemental Indenture, authenticate the Notes and any Additional Notes and perform its obligations hereunder. The Trustee shall not be accountable for the use or application by the Company of the Notes or any Additional Notes or the proceeds thereof.

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IN WITNESS WHEREOF, the parties hereto have caused this Fourth Supplemental Indenture to be duly executed as of the date first above written.

[Signature page to Fourth Supplemental Indenture]

Exhibit A — Form of 144A Global Note

THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY OR A NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN THE DEPOSITORY TRUST COMPANY OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT AND SUCH CERTIFICATE ISSUED IN EXCHANGE FOR THIS CERTIFICATE IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL, AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

[INSERT RESTRICTED SECURITIES LEGEND, IF APPLICABLE]

Gladstone Capital Corporation

3.75% Notes due 2027

Gladstone Capital Corporation, a corporation duly organized and existing under the laws of Maryland (herein called the “Company,” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of ____________________ (U.S. $ ____________________) on May 1, 2027, and to pay interest thereon from November 4, 2021 or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually on May 1 and November 1 of each year, commencing May 1, 2022, at the rate of 3.75% per annum, until the principal hereof is paid or made available for payment, and to pay the Additional Interest, if any, as defined in and payable pursuant to the Registration Rights Agreement. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date shall, as provided in such Indenture, be paid to the Person in whose name this Security is registered at the close of business on the Regular Record Date for such interest, which shall be April 15 or October 15, whether or not a Business Day, as the case may be, next preceding such Interest Payment Date. Any such interest not so punctually paid or duly provided for shall forthwith cease to be payable to the Holders of the Notes on such Regular Record Date and may either be paid to the Person in whose name this Security is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. This Security may be issued as part of a series.

Payment of the principal of (and premium, if any, on) and any such interest on this Security shall be made at the office of the Trustee located at 111 Fillmore Avenue, St. Paul, MN 55107, Attention: Gladstone Capital Corporation (3.75% Notes Due 2027) or at such other address as designated by the Trustee, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that, at the option of the Company payment of interest may be made by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register; provided, further, however, that, at the request of the registered Holder, the Company will pay the principal of (and premium, if any, on) and interest, if any, on the Securities by wire transfer of immediately available funds to an account at a bank in St. Paul, Minnesota, on the date when such amount is due and payable and as further set forth in Section 4.01 of the Indenture; provided further, however, that so long as this Security is registered to Cede & Co., such payment shall be made by wire transfer in accordance with the procedures established by The Depository Trust Company and the Trustee.

Reference is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

A-2

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

Dated:

This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

Dated:

A-3

Gladstone Capital Corporation

3.75% Notes due 2027

This Security is one of a duly authorized issue of Securities of the Company (herein called the “Securities”), issued and to be issued in one or more series under an Indenture, dated as of November 6, 2018 (herein called the “Base Indenture”), between the Company and U.S. Bank National Association, as Trustee (herein called the “Trustee,” which term includes any successor trustee under the Base Indenture), and reference is hereby made to the Base Indenture for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee, and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered, as supplemented by the Fourth Supplemental Indenture, dated as of November 4, 2021, by and between the Company and the Trustee (herein called the “Fourth Supplemental Indenture,” the Fourth Supplemental Indenture and the Base Indenture collectively are herein called the “Indenture”). In the event of any conflict between the Base Indenture and the Fourth Supplemental Indenture, the Fourth Supplemental Indenture shall govern and control.

This Security is one of the series designated on the face hereof, which series is initially limited in aggregate principal amount to $50,000,000. Under a Board Resolution, Officers’ Certificate pursuant to Board Resolutions or an indenture supplement, the Company may from time to time, without the consent of the Holders of Securities, issue additional Securities of this series (in any such case “Additional Securities”) having the same ranking and the same interest rate, maturity and other terms as the Securities; provided that, if such Additional Securities are not fungible with the Securities (or any other tranche of Additional Securities) for U.S. federal income tax purposes, then such Additional Securities will have a different CUSIP numbers from the Securities (and any such other tranche of Additional Securities). Any Additional Securities and the existing Securities will constitute a single series under the Indenture and all references to the relevant Securities herein shall include the Additional Securities unless the context otherwise requires. The aggregate amount of outstanding Securities represented hereby may from time to time be reduced or increased, as appropriate, to reflect exchanges and redemptions.

The Securities of this series shall be redeemable in whole or in part at any time or from time to time, at the option of the Company, at a Redemption Price (as determined by the Company) equal to the greater of the following amounts, plus, in each case, accrued and unpaid interest to, but excluding, the Redemption Date:

(a) 100% of the outstanding principal amount of the Securities to be redeemed, or

(b) the sum of the present values of the remaining scheduled payments of principal and interest (exclusive of accrued and unpaid interest to the Redemption Date) on the Securities to be redeemed, discounted to the Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) using the applicable Treasury Rate plus 50 basis points;

provided, however, that if the Company redeems any Securities on or after February 1, 2027, the Redemption Price for the Securities shall be equal to 100% of the principal amount of the Securities to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the Redemption Date.

For purposes of calculating the Redemption Price in connection with the redemption of the Securities, on any Redemption Date, the following terms have the meanings set forth below:

“Comparable Treasury Issue” means the United States Treasury security selected by the Reference Treasury Dealer as having a maturity comparable to the remaining term of the Securities to be redeemed that would be utilized, at the time of selection and in accordance with customary financing practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Securities being redeemed.

A-4

“Comparable Treasury Price” means (1) the average of the Reference Treasury Dealer Quotations for the Redemption Date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the Quotation Agent obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Quotation Agent” means a Reference Treasury Dealer selected by the Company.

“Reference Treasury Dealer” means each of any four primary U.S. government securities dealers selected by the Company.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Quotation Agent by such Reference Treasury Dealer at 3:30 p.m. New York City time on the third business day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per annum equal to the semi-annual equivalent yield-to-maturity of the Comparable Treasury Issue (computed as of the third business day immediately preceding the redemption), assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date. The Redemption Price and the Treasury Rate will be determined by the Company.

All determinations made by any Reference Treasury Dealer, including the Quotation Agent, with respect to determining the Redemption Price will be final and binding absent manifest error.

Notice of redemption shall be given in writing and mailed, first-class postage prepaid or by overnight courier guaranteeing next-day delivery, to each Holder of the Securities to be redeemed, not less than thirty (30) nor more than sixty (60) days prior to the Redemption Date, at the Holder’s address appearing in the Security Register. All notices of redemption shall contain the information set forth in Section 3.02(a) of the Base Indenture.

Any exercise of the Company’s option to redeem the Securities shall be done in compliance with the Indenture and the Investment Company Act, to the extent applicable.

If the Company elects to redeem only a portion of the Securities, the Trustee or, with respect to global Securities, the Depository will determine the method for selecting the particular Securities to be redeemed, in accordance with Section 1.01 of the Fourth Supplemental Indenture and Section 3.02(b) of the Base Indenture. In the event of redemption of this Security in part only, a new Security or Securities of this series and of like tenor for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.

Unless the Company defaults in payment of the Redemption Price, on and after the Redemption Date, interest shall cease to accrue on the Securities called for redemption.

Holders will have the right to require the Company to repurchase their Securities upon the occurrence of a Change of Control Repurchase Event as set forth in the Indenture.

A-5

The Indenture contains provisions for defeasance at any time of the entire indebtedness of this Security or certain restrictive covenants and Events of Default with respect to this Security, in each case upon compliance with certain conditions set forth in the Indenture.

If an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture. In the case of certain events of bankruptcy, insolvency or reorganization described in the Indenture, 100% of the principal of and accrued and unpaid interest (including Additional Interest), if any, on the Securities will automatically become due and payable.

The Holder of this Note is entitled to the benefits of the Registration Rights Agreement, dated as of November 4, 2021, by and between the Company and Raymond James & Associates, Inc.¹

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Company and the Trustee with the consent of the Holders of not less than a majority in principal amount of the Securities at the time Outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.

As provided in and subject to the provisions of the Indenture, the Holder of this Security shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Securities of this series, the Holders of not less than 25% in principal amount of the Securities of this series at the time Outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee indemnity, security, or both, reasonably satisfactory to the Trustee against the costs, expenses and liabilities to be incurred in compliance with such request, and the Trustee shall not have received from the Holders of a majority in principal amount of Securities of this series at the time Outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for sixty (60) days after receipt of such notice, request and offer of indemnity and/or security. The foregoing shall not apply to any suit instituted by the Holder of this Security for the enforcement of any payment of principal hereof or any premium or interest hereon on or after the respective due dates expressed herein.

No reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Security at the times, place and rate, and in the coin or currency, herein prescribed.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registrable in the Security Register, upon surrender of this Security for registration of transfer at the office or agency of the Company in any place where the principal of and any premium and interest

A-6

on this Security are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.

The Securities of this series are issuable only in registered form without coupons in denominations of $2,000 and any integral multiples of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange, but the Company, the Trustee, or the Security Registrar may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Security for registration of transfer, the Company, the Trustee, or the Security Registrar and any agent of the Company, the Trustee, or the Security Registrar shall treat the Person in whose name this Security is registered as the owner hereof for all purposes, whether or not this Security be overdue, and none of the Company, the Trustee, the Security Registrar, or any agent thereof shall be affected by notice to the contrary.

All terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

To the extent any provision of this Security conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling.

The Indenture and this Security shall be governed by and construed in accordance with the law of the State of New York.

A-7

Exhibit B — Form of IAI Global Note

THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY OR A NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN THE DEPOSITORY TRUST COMPANY OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT AND SUCH CERTIFICATE ISSUED IN EXCHANGE FOR THIS CERTIFICATE IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL, AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

[INSERT RESTRICTED SECURITIES LEGEND, IF APPLICABLE]

Gladstone Capital Corporation

3.75% Notes due 2027

Gladstone Capital Corporation, a corporation duly organized and existing under the laws of Maryland (herein called the “Company,” which term includes any successor Person under the Indenture hereinafter referred to), for value received, hereby promises to pay to Cede & Co., or registered assigns, the principal sum of ____________________ (U.S. $ ____________________) on May 1, 2027, and to pay interest thereon from November 4, 2021 or from the most recent Interest Payment Date to which interest has been paid or duly provided for, semi-annually on May 1 and November 1 of each year, commencing May 1, 2022, at the rate of 3.75% per annum, until the principal hereof is paid or made available for payment, and to pay the Additional Interest, if any, as defined in and payable pursuant to the Registration Rights Agreement. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date shall, as provided in such Indenture, be paid to the Person in whose name this Security is registered at the close of business on the Regular Record Date for such interest, which shall be April 15 or October 15, whether or not a Business Day, as the case may be, next preceding such Interest Payment Date. Any such interest not so punctually paid or duly provided for shall forthwith cease to be payable to the Holders of the Notes on such Regular Record Date and may either be paid to the Person in whose name this Security is registered at the close of business on a Special Record Date for the payment of such Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to Holders of Securities of this series not less than 10 days prior to such Special Record Date, or be paid at any time in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Securities of this series may be listed, and upon such notice as may be required by such exchange, all as more fully provided in said Indenture. This Security may be issued as part of a series.

Payment of the principal of (and premium, if any, on) and any such interest on this Security shall be made at the office of the Trustee located at 111 Fillmore Avenue, St. Paul, MN 55107, Attention: Gladstone Capital Corporation (3.75% Notes Due 2027) or at such other address as designated by the Trustee, in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts; provided, however, that, at the option of the Company payment of interest may be made by check mailed to the address of the Person entitled thereto as such address shall appear in the Security Register; provided, further, however, that, at the request of the registered Holder, the Company will pay the principal of (and premium, if any, on) and interest, if any, on the Securities by wire transfer of immediately available funds to an account at a bank in St. Paul, Minnesota, on the date when such amount is due and payable and as further set forth in Section 4.01 of the Indenture; provided further, however, that so long as this Security is registered to Cede & Co., such payment shall be made by wire transfer in accordance with the procedures established by The Depository Trust Company and the Trustee.

Reference is hereby made to the further provisions of this Security set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Security shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

B-2

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

Dated:

This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

Dated:

B-3

Gladstone Capital Corporation

3.75% Notes due 2027

This Security is one of a duly authorized issue of Securities of the Company (herein called the “Securities”), issued and to be issued in one or more series under an Indenture, dated as of November 6, 2018 (herein called the “Base Indenture”), between the Company and U.S. Bank National Association, as Trustee (herein called the “Trustee,” which term includes any successor trustee under the Base Indenture), and reference is hereby made to the Base Indenture for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee, and the Holders of the Securities and of the terms upon which the Securities are, and are to be, authenticated and delivered, as supplemented by the Fourth Supplemental Indenture, dated as of November 4, 2021, by and between the Company and the Trustee (herein called the “Fourth Supplemental Indenture,” the Fourth Supplemental Indenture and the Base Indenture collectively are herein called the “Indenture”). In the event of any conflict between the Base Indenture and the Fourth Supplemental Indenture, the Fourth Supplemental Indenture shall govern and control.

This Security is one of the series designated on the face hereof, which series is initially limited in aggregate principal amount to $50,000,000. Under a Board Resolution, Officers’ Certificate pursuant to Board Resolutions or an indenture supplement, the Company may from time to time, without the consent of the Holders of Securities, issue additional Securities of this series (in any such case “Additional Securities”) having the same ranking and the same interest rate, maturity and other terms as the Securities; provided that, if such Additional Securities are not fungible with the Securities (or any other tranche of Additional Securities) for U.S. federal income tax purposes, then such Additional Securities will have a different CUSIP numbers from the Securities (and any such other tranche of Additional Securities). Any Additional Securities and the existing Securities will constitute a single series under the Indenture and all references to the relevant Securities herein shall include the Additional Securities unless the context otherwise requires. The aggregate amount of outstanding Securities represented hereby may from time to time be reduced or increased, as appropriate, to reflect exchanges and redemptions.

The Securities of this series shall be redeemable in whole or in part at any time or from time to time, at the option of the Company, at a Redemption Price (as determined by the Company) equal to the greater of the following amounts, plus, in each case, accrued and unpaid interest to, but excluding, the Redemption Date:

(a) 100% of the outstanding principal amount of the Securities to be redeemed, or

(b) the sum of the present values of the remaining scheduled payments of principal and interest (exclusive of accrued and unpaid interest to the Redemption Date) on the Securities to be redeemed, discounted to the Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) using the applicable Treasury Rate plus 50 basis points;

provided, however, that if the Company redeems any Securities on or after February 1, 2027, the Redemption Price for the Securities shall be equal to 100% of the principal amount of the Securities to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the Redemption Date.

For purposes of calculating the Redemption Price in connection with the redemption of the Securities, on any Redemption Date, the following terms have the meanings set forth below:

“Comparable Treasury Issue” means the United States Treasury security selected by the Reference Treasury Dealer as having a maturity comparable to the remaining term of the Securities to be redeemed that would be utilized, at the time of selection and in accordance with customary financing practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Securities being redeemed.

B-4

“Comparable Treasury Price” means (1) the average of the Reference Treasury Dealer Quotations for the Redemption Date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the Quotation Agent obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations.

“Quotation Agent” means a Reference Treasury Dealer selected by the Company.

“Reference Treasury Dealer” means each of any four primary U.S. government securities dealers selected by the Company.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Quotation Agent by such Reference Treasury Dealer at 3:30 p.m. New York City time on the third business day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per annum equal to the semi-annual equivalent yield-to-maturity of the Comparable Treasury Issue (computed as of the third business day immediately preceding the redemption), assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date. The Redemption Price and the Treasury Rate will be determined by the Company.

All determinations made by any Reference Treasury Dealer, including the Quotation Agent, with respect to determining the Redemption Price will be final and binding absent manifest error.

Notice of redemption shall be given in writing and mailed, first-class postage prepaid or by overnight courier guaranteeing next-day delivery, to each Holder of the Securities to be redeemed, not less than thirty (30) nor more than sixty (60) days prior to the Redemption Date, at the Holder’s address appearing in the Security Register. All notices of redemption shall contain the information set forth in Section 3.02(a) of the Base Indenture.

Any exercise of the Company’s option to redeem the Securities shall be done in compliance with the Indenture and the Investment Company Act, to the extent applicable.

If the Company elects to redeem only a portion of the Securities, the Trustee or, with respect to global Securities, the Depository will determine the method for selecting the particular Securities to be redeemed, in accordance with Section 1.01 of the Fourth Supplemental Indenture and Section 3.02(b) of the Base Indenture. In the event of redemption of this Security in part only, a new Security or Securities of this series and of like tenor for the unredeemed portion hereof will be issued in the name of the Holder hereof upon the cancellation hereof.

Unless the Company defaults in payment of the Redemption Price, on and after the Redemption Date, interest shall cease to accrue on the Securities called for redemption.

Holders will have the right to require the Company to repurchase their Securities upon the occurrence of a Change of Control Repurchase Event as set forth in the Indenture.

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The Indenture contains provisions for defeasance at any time of the entire indebtedness of this Security or certain restrictive covenants and Events of Default with respect to this Security, in each case upon compliance with certain conditions set forth in the Indenture.

If an Event of Default with respect to Securities of this series shall occur and be continuing, the principal of the Securities of this series may be declared due and payable in the manner and with the effect provided in the Indenture. In the case of certain events of bankruptcy, insolvency or reorganization described in the Indenture, 100% of the principal of and accrued and unpaid interest (including Additional Interest), if any, on the Securities will automatically become due and payable.

The Holder of this Note is entitled to the benefits of the Registration Rights Agreement, dated as of November 4, 2021, by and between the Company and Raymond James & Associates, Inc.²

The Indenture permits, with certain exceptions as therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Holders of the Securities of each series to be affected under the Indenture at any time by the Company and the Trustee with the consent of the Holders of not less than a majority in principal amount of the Securities at the time Outstanding of each series to be affected. The Indenture also contains provisions permitting the Holders of specified percentages in principal amount of the Securities of each series at the time Outstanding, on behalf of the Holders of all Securities of such series, to waive compliance by the Company with certain provisions of the Indenture and certain past defaults under the Indenture and their consequences. Any such consent or waiver by the Holder of this Security shall be conclusive and binding upon such Holder and upon all future Holders of this Security and of any Security issued upon the registration of transfer hereof or in exchange herefor or in lieu hereof, whether or not notation of such consent or waiver is made upon this Security.

As provided in and subject to the provisions of the Indenture, the Holder of this Security shall not have the right to institute any proceeding with respect to the Indenture or for the appointment of a receiver or trustee or for any other remedy thereunder, unless such Holder shall have previously given the Trustee written notice of a continuing Event of Default with respect to the Securities of this series, the Holders of not less than 25% in principal amount of the Securities of this series at the time Outstanding shall have made written request to the Trustee to institute proceedings in respect of such Event of Default as Trustee and offered the Trustee indemnity, security, or both, reasonably satisfactory to the Trustee against the costs, expenses and liabilities to be incurred in compliance with such request, and the Trustee shall not have received from the Holders of a majority in principal amount of Securities of this series at the time Outstanding a direction inconsistent with such request, and shall have failed to institute any such proceeding, for sixty (60) days after receipt of such notice, request and offer of indemnity and/or security. The foregoing shall not apply to any suit instituted by the Holder of this Security for the enforcement of any payment of principal hereof or any premium or interest hereon on or after the respective due dates expressed herein.

No reference herein to the Indenture and no provision of this Security or of the Indenture shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and any premium and interest on this Security at the times, place and rate, and in the coin or currency, herein prescribed.

As provided in the Indenture and subject to certain limitations therein set forth, the transfer of this Security is registrable in the Security Register, upon surrender of this Security for registration of transfer at the office or agency of the Company in any place where the principal of and any premium and interest

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on this Security are payable, duly endorsed by, or accompanied by a written instrument of transfer in form satisfactory to the Company and the Security Registrar duly executed by, the Holder hereof or his attorney duly authorized in writing, and thereupon one or more new Securities of this series and of like tenor, of authorized denominations and for the same aggregate principal amount, will be issued to the designated transferee or transferees.

The Securities of this series are issuable only in registered form without coupons in denominations of $2,000 and any integral multiples of $1,000 in excess thereof. As provided in the Indenture and subject to certain limitations therein set forth, Securities of this series are exchangeable for a like aggregate principal amount of Securities of this series and of like tenor of a different authorized denomination, as requested by the Holder surrendering the same.

No service charge shall be made for any such registration of transfer or exchange, but the Company, the Trustee, or the Security Registrar may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

Prior to due presentment of this Security for registration of transfer, the Company, the Trustee, or the Security Registrar and any agent of the Company, the Trustee, or the Security Registrar shall treat the Person in whose name this Security is registered as the owner hereof for all purposes, whether or not this Security be overdue, and none of the Company, the Trustee, the Security Registrar, or any agent thereof shall be affected by notice to the contrary.

All terms used in this Security which are defined in the Indenture shall have the meanings assigned to them in the Indenture.

To the extent any provision of this Security conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling.

The Indenture and this Security shall be governed by and construed in accordance with the law of the State of New York.

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