The Company's methodology for allocating the purchase price relating to purchase acquisitions is determined through established and generally accepted valuation techniques. Goodwill is measured as the excess of the cost of the acquisition over the sum of the amounts assigned to tangible and identifiable intangible assets acquired less liabilities assumed. The Company assigns assets acquired (including goodwill) and liabilities assumed to one or more reporting units as of the date of acquisition. If the products obtained in an acquisition are assigned to multiple reporting units, the goodwill is distributed to the respective reporting units as part of the purchase price allocation process.

Goodwill and purchased intangible assets with indefinite useful lives are not amortized but are reviewed for impairment annually during the fourth quarter of each fiscal year and whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. The process of evaluating the potential impairment of goodwill and intangible assets requires significant judgment.

The Company regularly monitors current business conditions and other factors including, but not limited to, adverse industry or economic trends, restructuring actions and lower projections of profitability that may impact future operating results. During the quarter ended June 30, 2022, following softening industry demand for flexible printed

circuit board (“PCB”) via drilling systems and declines in projected operating results for its ESB reporting unit, the Company evaluated the carrying values of goodwill, purchased intangible assets and other long-lived assets assigned to the reporting unit and determined the carrying values were recoverable. The Company performed its analysis using the income approach and key underlying assumptions included forecasted revenue, gross profit and operating expenses as well as discount rate. Fair value estimates are based on complex series of judgments about future events and uncertainties and rely heavily on estimates and assumptions that have been deemed reasonable by the Company's management. There are inherent uncertainties and management judgment required in these determinations. In its quantitative assessment of the reporting unit, the Company estimated fair value exceeded carrying value by 10%. The Company determined that there were no further triggering events that required an impairment assessment during the remainder of the year ended December 31, 2022 for its ESB reporting unit.

The changes in the carrying amount of goodwill and accumulated impairment losses were as follows:


	2022							2021
	Gross Carrying Amount		Accumulated Impairment Loss			Net		Gross Carrying Amount			Accumulated Impairment Loss			Net
Beginning balance at January 1	$	1,374	$	(146	)	$	1,228	$	1,212		$	(146	)	$	1,066
Acquired goodwill (1)		3,064		—			3,064		168			—			168
Foreign currency translation		16		—			16		(6	)		—			(6	)
Ending balance at December 31	$	4,454	$	(146	)	$	4,308	$	1,374		$	(146	)	$	1,228

(1)

During the year ended December 31, 2022, the Company recorded goodwill related to the Atotech Acquisition. During the year ended December 31, 2021, the Company recorded goodwill related to the Photon Control Acquisition. See Note 4 to the Notes to Consolidated Financial Statements.

Intangible Assets

Components of the Company's intangible assets are comprised of the following:


As of December 31, 2022	Gross		Accumulated Impairment Charges			Accumulated Amortization			Foreign Currency Translation		Net
Completed technology(1)	$	1,151	$	—		$	(303	)	$	4	$	852
Customer relationships(1)		2,072		(1	)		(190	)		11		1,892
Patents, trademarks, trade names and other(1)		498		—			(71	)		2		429
	$	3,721	$	(1	)	$	(564	)	$	17	$	3,173

(1)

During the year ended December 31, 2022, the Company recorded $2,726 of separately identified intangible assets related to the Atotech Acquisition, including $595 in completed technology, $1,756 in customer relationships and $375 in patents, trademarks, trade names and other.


As of December 31, 2021	Gross		Accumulated Impairment Charges			Accumulated Amortization			Foreign Currency Translation			Net
Completed technology(1)	$	556	$	—		$	(242	)	$	—		$	314
Customer relationships(1)		318		(1	)		(124	)		(1	)		192
Patents, trademarks, trade names and other(1)		123		—			(52	)		(1	)		70
	$	997	$	(1	)	$	(418	)	$	(2	)	$	576

(1)

During the year ended December 31, 2021, the Company recorded $121 of separately identified intangible assets related to the Photon Control Acquisition, representing $110 in completed technology, $9 in customer relationships and $2 in patents, trademarks, trade names and other.

Aggregate amortization expense related to acquired intangible assets for 2022, 2021 and 2020 was $146, $55 and $55, respectively. Aggregate net amortization expense related to acquired intangible assets for future years is:

The Company excluded from the above table intangible assets of $56 of indefinite-lived trademarks and trade names, and $190 of in-process research and development, which were not subject to amortization.