Ultra Clean Holdings, Inc.

9. STOCKHOLDERS’ EQUITY AND NONCONTROLLING INTERESTS

Treasury Stock

On October 20, 2022, the Board of Directors approved a share repurchase program authorizing the Company to purchase up to an aggregate of $150 million of the Company’s common stock over athree-year period.

On October 23, 2025, the Board of Directors approved a renewal of the share repurchase program, authorizing the Company to repurchase up to $150.0 million of its common stock over athree-year period. No shares have been repurchased under the renewed program in the first half of 2026. For the three and six months ended June 27, 2025, approximately 0.2 million shares were repurchased under this program with aggregate cost of $3.4 million.

During the six months ended June 26, 2026, the Company repurchased 0.7 million shares for $40.3 million through a privately negotiated transaction with one of the initial purchasers of the Company’s convertible notes. These shares are held as treasury stock. The Company accounts for treasury stock using the cost method. There wereno share repurchases during the three months ended June 26, 2026.

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Non-controlling Interests

Noncontrolling interests are recognized to reflect the portion of equity in the Company’s consolidated subsidiaries that is not attributable, directly or indirectly, to the controlling stockholder. The Company’s consolidated entities include partially owned subsidiaries that provide outsourced cleaning and recycling of precision parts for the semiconductor industry through operating facilities in South Korea and China. The ownership interests held by other parties in these subsidiaries are presented as noncontrolling interests in the accompanying Consolidated Financial Statements. Net income (loss) attributable to noncontrolling interests is allocated based on the respective ownership interests and continues to be attributed even if such allocation results in a deficit noncontrolling interests balance.