X0609 4 2026-05-08 0 0001275014 Ultra Clean Holdings, Inc. UCTT 0001878029 McKibben Jeffrey L. false ULTRA CLEAN HOLDINGS, INC. 26462 CORPORATE AVENUE HAYWARD CA 94545 0 1 0 0 Chief Information Officer 0 Common Stock 2026-05-08 4 S 0 2500 86.4784 D 15554 D This is the weighted average sale price. Shares were sold in multiple transactions at prices ranging from $86.46 to $86.55. The reporting person undertakes to provide to the issuer, any security holder of the issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote (1) to this Form 4. /s/ Paul Y. Cho, as attorney-in-fact for Jeffrey L. McKibben 2026-05-12