144 0002104071 XXXXXXXX LIVE 0000811596 Kaiser Aluminum 001-09447 1550 West McEwen Drive, Suite 500 Franklin TN 37067 6292527040 Iulian Gheorghe Officer common UBS Financial Services Inc

1000 Harbor Blvd 3rd Floor Weehawken NJ 07086

175 30488.5 16340606 04/27/2026 NASDAQ common 02/19/2026 RSU Kaiser Aluminum N 175 04/27/2026 cash Y 04/27/2026 /s/JOSEPH CASSIDY, for UBS Financial Services Inc, as attorney-in-fact for Iulian Gheorghe