Ultra Clean Holdings, Inc.

3. FAIR VALUE

The fair value hierarchy requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The following table summarizes, for assets or liabilities measured at fair value, the respective fair value and the classification by level of input within the fair value hierarchy:

The estimated fair value of pension obligation is based on expected years of service and average compensation. The valuation model used to value pension obligation utilizes mortality rate, inflation, interest rate risks and changes in the life expectancy for pensioners. These assumptions are routinely made in the appraisal process by the independent actuary resulting in a Level 3 classification. As of September 26, 2025, the Company’s aggregate pension benefit obligations was $13.9 million and the fair value of the pension plan assets was $11.2 million, resulting in underfunded pension benefit obligations of $2.7 million. The Company recognizes the overfunded or underfunded status of defined benefit pension plans, measured as the difference between the fair value of the plan assets and the benefit obligation. Each overfunded plan is recognized as an asset and each underfunded plan is recognized as a liability.

Prior to fiscal year 2025, the Company measured its contingent earn-out liabilities at fair value on a recurring basis using a Monte Carlo simulation model. The significant unobservable inputs used in the model included the forecasted operating profit of the acquired business during the earn-out period ending in calendar year 2025. Significant increases or decreases to the forecasted results would result in a significantly higher or lower liability, with a higher liability capped by the contractual maximum of the contingent earn-out obligation. Ultimately, the liability will be equivalent to the amount paid, and the difference between the fair value estimate and amount paid will be recorded in earnings. The amount paid that is less than or equal to the contingent earn-out liability on the acquisition date is reflected as cash used in financing activities in the consolidated statements of cash flows. Any amount paid in excess of the contingent earn-out liability on the acquisition date will be reflected as cash used in operating activities in the consolidated statements of cash flows.

In the first quarter of fiscal year 2025, the Company reassessed the fair value of the contingent earn-out associated with the acquisition of HIS, decreasing the fair value from $0.1 million as of December 27, 2024, tozero. The $0.1 million decrease was recorded as Other income (expense), net in the Condensed Consolidated Statements of Operations for the nine months ended September 26, 2025. The change in fair value was primarily due to lower-than-expected financial performance. There wasno change in the fair value estimate during the third quarter of fiscal year 2025.

For the three and nine months ended September 27, 2024, the Company recognized $0.8 million of loss and $22.0 million of gain, respectively, related to the change in the fair value of contingent earn-out liability. These amounts were recorded within other income (expense), net in the Condensed Consolidated Statements of Operations.

There were no transfers in or out of any level during the three and nine months ended September 26, 2025 and September 27, 2024. Fair value adjustments were noncash, and therefore did not impact the Company’s liquidity or capital resources.

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