Form 8-K

8-K — GLADSTONE CAPITAL CORP

Accession: 0001193125-26-252617

Filed: 2026-06-02

Period: 2026-06-01

CIK: 0001143513

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — d21227d8k.htm (Primary)

EX-99.1 (d21227dex991.htm)

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8-K

8-K (Primary)

Filename: d21227d8k.htm · Sequence: 1

8-K

GLADSTONE CAPITAL CORP false 0001143513 0001143513 2026-06-01 2026-06-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 2, 2026 (June 1, 2026)

Gladstone Capital Corporation

(Exact name of registrant as specified in its charter)

Maryland

814-00237

54-2040781

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

1521 Westbranch Drive, Suite 100

McLean, Virginia

22102

(Address of principal executive offices)

(Zip Code)

(703) 287-5800

(Registrant’s telephone number, including area code)

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading

symbol

Name of each exchange

on which registered

Common Stock, $0.001 par value per share

GLAD

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On June 1, 2026, the Board of Directors (the “Board”) of Gladstone Capital Corporation (the “Company”) elected George “Chip” Stelljes, III to the Board, effective June 1, 2026. Mr. Stelljes will join the 2028 class of Directors for the Company as an independent director, with a term expiring at the Company’s 2028 annual meeting of stockholders. The Board has also named Mr. Stelljes to its Compensation Committee, its Ethics, Nominating and Corporate Governance Committee, and its Valuation Committee.

Mr. Stelljes will be compensated on a pro-rated basis for his service on the Board in accordance with the Company’s compensation program for independent directors, as set forth in the Company’s proxy statement for its 2026 annual meeting of stockholders.

There are no other arrangements or understandings between Mr. Stelljes and any other person pursuant to which he was elected as a director of the Company. There are no transactions between Mr. Stelljes and the Company that would be reportable under Item 404(a) of Regulation S-K.

Item 7.01

Regulation FD Disclosure.

On June 2, 2026, the Company issued a press release (the “Press Release”) announcing Mr. Stelljes’ election to the Board. A copy of the Press Release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in Item 7.01 of this Current Report on Form 8-K, as well as Exhibit 99.1 attached hereto, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

No.

Description

99.1

Press Release dated June 2, 2026

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: June 2, 2026

GLADSTONE CAPITAL CORPORATION

By:

/s/ Nicole Schaltenbrand

Nicole Schaltenbrand

Chief Financial Officer & Treasurer

EX-99.1

Filename: d21227dex991.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Gladstone Capital Corporation Announces Election of

George “Chip” Stelljes, III as Director

McLean, VA, June 2, 2026: Gladstone Capital Corporation (Nasdaq: GLAD) (the “Company”) announced that George “Chip”

Stelljes, III has been elected to the 2028 class of directors for the Company, effective June 1, 2026. Mr. Stelljes has also been appointed to serve on the Company’s Compensation Committee, Ethics, Nominating & Corporate

Governance Committee and Valuation Committee. In connection with Mr. Stelljes’ appointment, the size of the Company’s board of directors has been expanded from seven to eight directors. Mr. Stelljes was selected to serve as a

director due to his more than twenty-five years of experience in the investment analysis, management, and advisory industries.

“We are excited to

strengthen our board with the appointment of Chip Stelljes,” said David Gladstone, Chairman of the Company’s board of directors. “His prior service with the Gladstone companies and his deep experience in private equity fund

investment will be a valuable asset to the Company as we continue to grow.”

Mr. Stelljes is currently the managing partner of St. John’s

Capital, LLC, a vehicle used to make private equity investments. From 2001 to 2013, Mr. Stelljes held various senior positions with the Gladstone Companies, including serving as the chief investment officer, president and a director of

Gladstone Capital Corporation, Gladstone Investment Corporation, Gladstone Commercial Corporation, and Gladstone Management Corporation. Prior to his service at the Gladstone companies, for 23 years, Mr. Stelljes served in a variety of roles at

multiple private equity and venture capital funds, including Patriot Capital, Camden Partners, and Columbia Capital as well as Allied Capital.

Mr. Stelljes is currently the chairman of the board of directors of Equalize Community Development Fund, a

closed-end investment company that operates as an interval fund and an independent director of Oxford Square Capital Corporation, a publicly-traded, closed-end

management investment company. He is also a former board member and regional president of the National Association of Small Business Investment Companies. Mr. Stelljes holds an MBA from the University of Virginia and a BA in Economics from

Vanderbilt University.

About Gladstone Capital Corporation: Gladstone Capital Corporation is a publicly-traded business development company that

invests in debt and equity securities, consisting primarily of secured first and second lien term loans to lower middle market businesses in the United States. For more information, please visit www.gladstonecapital.com.

About the Gladstone Companies: Information on the business activities of all the Gladstone family of funds can be found

at www.gladstonecompanies.com.

CONTACT: For further information: Gladstone Capital Corporation, (703)

287-5893.

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