ADTRAN Holdings Inc. filed SEC Form 8-K: Leadership Update, Other Events, 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

ADTRAN Holdings, Inc.

(Exact name of Registrant as Specified in Its Charter)

(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:

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

On June 23, 2026, the Board of Directors (the “Board”) of ADTRAN Holdings, Inc. (the “Company”), upon the recommendation of the Board’s Nominating and Corporate Governance Committee, voted unanimously to increase the size of the Board from six (6) to seven (7) directors and to elect Anne DelSanto to fill the vacancy created by the increase in the size of the Board, effective as of July 1, 2026 (the “Effective Date”). In connection with her election to the Board, Ms. DelSanto was appointed to the Compensation Committee of the Board, effective as of the Effective Date. The Board has determined that Ms. DelSanto qualifies as an “independent director” under Nasdaq listing standards.

There are no arrangements or understandings between Ms. DelSanto and any other person pursuant to which Ms. DelSanto was selected as a director of the Company. There are no related person transactions (within the meaning of Item 404(a) of Regulation S-K promulgated by the Securities and Exchange Commission) between Ms. DelSanto and the Company. Ms. DelSanto will receive compensation for her Board service in accordance with the Company’s standard compensation arrangements for non-employee directors, which are described under the caption “2025 Director Compensation” in the Company’s definitive proxy statement on Schedule 14A filed with the Securities and Exchange Commission on March 27, 2026, as adjusted by the Board from time to time.

Item 8.01 Other Events.

On June 25, 2026, the Company issued a press release announcing the appointment of Ms. DelSanto to the Board, which press release contains additional biographical information about Ms. DelSanto. A copy of this press release is attached hereto as Exhibit 99.1.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

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.