Diamond Hill Investment Group Inc. filed SEC Form 8-K: Results of Operations and Financial Condition, Leadership Update, Financial Statements and Exhibits

United States

Securities and Exchange Commission

Washington, D.C. 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): October 30, 2025

DIAMOND HILL INVESTMENT GROUP, INC.

(Exact name of registrant as specified in its charter)

325 John H. McConnell Blvd, Suite 200, Columbus, Ohio 43215

(Address of principal executive offices) (Zip Code)

Registrant's telephone number, including area code: (614) 255-3333

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:

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 2.02 Results of Operations and Financial Condition.

On October 30, 2025, Diamond Hill Investment Group, Inc. (the “Company”) issued a press release reporting its results of operations for the fiscal quarter ended September 30, 2025. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this Item 2.02 and in Exhibit 99.1 shall not be deemed to be filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, unless the Company specifically states that the information is to be considered filed under the Exchange Act or incorporates the information by reference into a filing under the Exchange Act or the Securities Act of 1933, as amended. By furnishing the information in this Form 8-K and the attached exhibit, the Company is making no admission as to the materiality of any information in this Form 8-K or the exhibit.

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

The Company’s Amended and Restated Code of Regulations (“Regulations”) provides that the Board may fix or change the number of directors and may fill any director’s office that is created by an increase in the number of directors; provided, however, that the Board may not increase the number of directors to more than fifteen nor reduce the number of directors to less than five. Pursuant to the Regulations, on October 29, 2025, the Board: (1) increased the size of the Board from seven directors to eight directors, and (2) appointed Diane C. Nordin to serve as a director on the Board and fill the seat created by the increase in the number of directors on the Board. The Board appointed Ms. Nordin, whom the Board determined is an independent director, upon the recommendation of its Nominating and Governance Committee. Ms. Nordin has also been appointed as a member of the Company’s Audit Committee, Compensation Committee, and Nominating and Governance Committee. Ms. Nordin’s current term continues through the Company’s annual meeting of shareholders in 2026 (“Annual Meeting”).

There are no arrangements or understandings between Ms. Nordin and any other person pursuant to which she was selected as a director. There are no family relationships between Ms. Nordin and any director or executive officer of the Company, and she does not have any direct or indirect material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.

Between her appointment and the Annual Meeting, Ms. Nordin will receive cash compensation of $80,000, which represents half of the value of the annual restricted stock awarded to directors, and two quarterly director fee payments of $10,000 each, all of which is consistent in value with the Company’s customary director compensation program.

Item 9.01 Financial Statements and Exhibits

SIGNATURES

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