Form 4 Filing for Kaiser Aluminum Corp.

Brett Wilcox, a director at Kaiser Aluminum Corp. (KALU), reported the sale of 15,000 shares of common stock on April 27, 2026. The transactions occurred at prices ranging from $173.60 to $175.23 per share, with a weighted average sale price of $174.44 per share. Following these sales, Wilcox directly owns 1,905 shares and indirectly owns 9,887 shares through the Wilcox Revocable Trust. The reporting person has undertaken to provide detailed information on the sale prices upon request by the SEC, the Registrant, or a security holder.