144/A 0001628280-25-053563 0001551869 XXXXXXXX LIVE 0000811596 Kaiser Aluminum Corp 001-09447 1550 West McEwen Drive Suite 500 Franklin TN 37067 629-252-7162 Keith Harvey CEO Kaiser Aluminum Merrill

39001 w 12 Mile Rd Farmington Hills MI 48331

33000 2980039.79 31032 11/21/2025 NASQ Common Stock 03/05/2020 Restricted Stock from Comp Plan Keith Harvey N 25063 11/21/2025 cash Common Stock 03/05/2021 Restricted Stock from Comp Plan and Performance Shares Keith Harvey N 13698 11/21/2025 cash Common Stock 03/05/2022 Restricted Stock from Comp Plan and Performance Shares Keith Harvey N 14674 11/21/2025 cash Common Stock 03/05/2023 Restricted Stock from Comp Plan Keith Harvey N 18909 11/21/2025 cash Common Stock 07/29/2024 Restricted Stock from Comp Plan Keith Harvey N 2588 11/21/2025 cash Common Stock 07/27/2022 Restricted Stock from Comp Plan Keith Harvey N 18195 11/21/2025 cash Y 11/21/2025 Heather Hernesko