10. Intangible Assets and Goodwill

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The gross carrying amount and accumulated amortization of the Company’s acquired identifiable intangible assets as of December 31, 2023 are as follows (in thousands):

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The gross carrying amount and accumulated amortization of the Company’s acquired identifiable intangible assets as of December 31, 2022 are as follows (in thousands):

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The change in the gross carrying amount of the acquired technology and customer relationships, trade name and other from the years ended December 31, 2022 to 2023 was primarily due to changes in foreign currency translation.

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Amortization expense for acquired identifiable intangible assets for the years ended December 31, 2023, 2022 and 2021 was $19.1 million, $21.2 million and $2.5 million, respectively.

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Estimated amortization expense for subsequent years was as follows (in thousands):

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The change in the carrying amount of goodwill for the year ended December 31, 2023 was as follows (in thousands):

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Based on the results of our annual review, the Company recognized an impairment charge of $249.5 million for the year ended December 31, 2023. The Company’s stock price declined below book value during the fourth quarter of 2023. Management believes the decline of the stock price was due primarily to missed projections and reduced liquidity. The Company’s analyses did not indicate impairment of goodwill for the years ended December 31, 2022 and 2021. Goodwill was $0 and $248.6 million as of December 31, 2023 and 2022 respectively. See Note 2, “Summary of Significant Accounting Policies”, for a full description of the Company’s goodwill accounting policy.