Kaiser Aluminum Corp — Current Report (Form 8-K)

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

KAISER ALUMINUM CORPORATION

(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 4, 2026, Kaiser Aluminum Corporation (the “Company”) held its Annual Meeting of Stockholders (the “2026 Annual Meeting”). At the 2026 Annual Meeting, the stockholders of the Company, upon recommendation of the Company’s Board of Directors (the “Board”), approved the amendment and restatement of the Kaiser Aluminum Corporation 2021 Equity and Incentive Compensation Plan, as amended (the “2021 Plan”), to increase the number of shares of common stock, par value $0.01 per share, of the Company (“Common Stock”), available for awards under the 2021 Plan by 395,000 shares. We refer to the 2021 Plan, as newly amended and restated at the 2026 Annual Meeting, as the “Amended 2021 Plan.” Other than the increase in shares described above, the Amended 2021 Plan does not make any other material changes to the 2021 Plan.

Subject to adjustment as described in the Amended 2021 Plan and the Amended 2021 Plan’s share counting rules, a total of 1,183,000 shares of Common Stock (consisting of 395,000 new shares approved by the Company’s stockholders at the 2026 Annual Meeting, 263,000 shares approved by the Company’s stockholders in 2024, and 525,000 shares approved by the Company’s stockholders in 2021) are available for awards granted under the Amended 2021 Plan.

This description of the Amended 2021 Plan is qualified in its entirety by reference to the full text of the Amended 2021 Plan, which is incorporated by reference as Exhibit 10.1 to this Current Report on Form 8-K.

Item 5.07 Submission of Matters to a Vote of Security Holders.

Below are the matters that were voted upon at the 2026 Annual Meeting and the final voting results as reported by our inspector of elections.

The other directors with terms continuing after the 2026 Annual Meeting are Michael C. Arnold, David A. Foster, Kimberly T. Glas, Richard P. Grimley, Keith A. Harvey and Donald J. Stebbins.

The number of shares voting “for” constituted 98.68% of the total number of shares represented and entitled to vote at the meeting and actually voted on the proposal.

The number of shares voting “for” constituted 98.20% of the total number of shares represented and entitled to vote at the meeting and actually voted on the proposal.

The number of shares voting “for” constituted 94.43% of the total number of shares represented and entitled to vote at the meeting and actually voted on the proposal.

Item 9.01 Financial Statements and 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.