Form 4 Filing by Yoram Rubanenko

Yoram Rubanenko, Executive Vice President of COSTCO WHOLESALE CORP /NEW, reported a transaction involving Common Stock on September 10, 2026. The transaction involved the acquisition of 4,129 shares at a price of $0.00 per share, with a footnote indicating this was a grant made on October 22, 2025, subject to performance conditions that have been satisfied. The earned awards vest over five years, with accelerated vesting possible upon certain anniversaries of service. Subsequently, 1,695.952 shares were disposed of at a price of $902.38 per share. Following these transactions, Mr. Rubanenko directly owns 10,680.167 shares.