Ultra Clean Holdings Inc

11. REVENUE RECOGNITION

Revenue is recognized when the Company satisfies the performance obligations as evidenced by the transfer of control of the promised goods or services to the Company’s customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services.

The Company sells its products and services primarily to customers in the semiconductor capital equipment industry. The Company’s revenues are highly concentrated and therefore highly dependent upon a small number of customers. Typical payment terms with our customers range from thirty tosixty days.

The Company’s Products business segment provides warranty on its products for a period of up totwo years and provides for warranty costs at the time of sale based on historical activity. Determination of the warranty reserve requires the Company to make estimates of product return rates and expected costs to repair or replace the products under warranty. If actual return rates and/or repair and replacement costs differ significantly from these estimates, adjustments to recognize additional cost of revenues may be required in future periods. The warranty reserve is included in other current liabilities on the Condensed Consolidated Balance Sheets and is not considered significant.

The Company’s products are manufactured and services provided at the Company’s locations throughout the Americas, Asia Pacific and Europe and the Middle East (“EMEA”). Sales to customers are initiated through a purchase order and are governed by our standard terms and conditions, written agreements, or both. Revenue is recognized when performance obligations under the terms of an agreement with a customer are satisfied; generally, this occurs with the transfer of control of the products or when the Company provides the services. Based on the enforceable rights included in our agreements or prevailing terms and conditions, products produced by the Company without an alternative use are not protected by an enforceable right of payment that includes a reasonable profit throughout the duration of the agreement. Consignment sales are recognized in revenue at the earlier of the period that the goods are consumed or after a period of time subsequent to receipt by the customer as specified by terms of the agreement, provided control of the promised goods or services has transferred.

Revenue is measured as the amount of consideration we expect to receive in exchange for transferring goods or providing services. Sales, value-add, and other taxes we collect concurrent with revenue-producing activities are excluded from revenue. Certain of our customers may receive cash-based incentives, such as rebates or credits, which are accounted for as variable consideration. We estimate these amounts based on the expected amount to be provided to customers and reduce revenues recognized. As of March 28, 2025, the total unpaid rebates amounted to $2.3 million, of which $0.6 million was recorded as a reduction to accounts receivable, and $1.7 million was recorded within accounts payable. Accruals for unpaid customer rebates of $2.3 million as of December 27, 2024, were netted against accounts receivable. The Company’s disaggregated revenues are apportioned by segments within the Company’s Condensed Consolidated Statement of Operations. Certain services performed by the Company related to products sold to customers are included in Products revenue in the Condensed Consolidated Statement of Operations. These services are not material for any of the periods presented.

The Company’s principal markets include Americas, Asia Pacific and EMEA. The Company’s foreign operations are conducted primarily through its subsidiaries in China, Malaysia, Singapore, Israel, Taiwan, South Korea, the United

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Kingdom and the Czechia. Revenues by geographic area are categorized based on the customer’s location to which the products were shipped or services were performed. The following table sets forth revenue by geographic area (in millions):

The Company’s most significant customers (having individually accounted for 10% or more of revenues) are from Products segment and their related revenues as a percentage of total revenues were as follows:

Two customers’ gross accounts receivable balances, Lam Research Corporation and ASML Holding NV, were individually greater than 10% of gross accounts receivable as of March 28, 2025, in the aggregate approximately 26.7% of the Company’s total gross accounts receivable.

Three customers’ gross accounts receivable balances, Applied Materials, Inc., Lam Research Corporation and ASML Holding NV were individually greater than 10% of gross accounts receivable as of December 27, 2024, in the aggregate approximately 41.9% of total gross accounts receivable.