On April 17, 2023, the board of directors of Kaiser Aluminum Corporation appointed Richard P. Grimley as a director to fill the vacancy on the Board. Mr. Grimley, 64, has been a consultant since June 2021 and previously served as Senior Vice President of Global Operations of Ball Corporation from July 2016 to June 2021. Prior to joining Ball Corporation, Mr. Grimley held various senior management positions with Rexam and its subsidiaries, including Global Director of Operations of Rexam Group, President and Chief Executive Officer of North America of Rexam, Chief Operating Officer of North and South Americas of Rexam Beverage Cans, and Vice President of Manufacturing of Rexam.

Mr. Grimley holds a Bachelor's degree in business administration from the University of Iowa and a Master's degree in business administration from Benedictine University. The Board appointed Mr. Grimley as a director because of his extensive experience in the aluminum packaging industry and manufacturing operations. Mr. Grimley will serve as a Class III director with a term expiring at the Company's 2024 annual meeting of stockholders and will serve on the Board's compensation and ESG committees.