Ultra Clean Holdings, Inc.

4. GOODWILL AND INTANGIBLE ASSETS

Goodwill

Goodwill represents the excess of the consideration transferred over the fair value of tangible and identifiable intangible assets acquired, less liabilities assumed in a business combination. During the six months ended June 26, 2026, the Company didnot recognize any impairment charges or additions to goodwill. Details of aggregate goodwill of the Company are as follows:

Intangible Assets

Intangible assets are generally recorded in connection with business acquisitions and are amortized over their estimated useful lives. The Company evaluates the useful lives of its intangible assets each reporting period and reviews such assets for impairment when events or changes in circumstances indicate that the carrying value may not be recoverable.

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Details of intangible assets were as follows:

*The Company concluded that the asset life of UCT tradename of $9.0 million is indefinite and is therefore not amortized but is reviewed for impairment at least annually and whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable.

The Company amortizes its intangible assets on a straight-line or accelerated basis over the estimated economic life of the assets. Amortization expense was approximately $6.8 million and $13.7 million for the three and six months ended June 26, 2026, respectively. For the three and six months ended June 27, 2025, amortization expense was approximately $7.0 million and $14.3 million, respectively. Amortization expense related to recipes, standard operating procedures, developed technology and certain intellectual property/know-how is included in cost of revenues, while the remaining amortization expense is included in general and administrative expense. As of June 26, 2026, future estimated amortization expense is expected to be as follows: