7. Intangible Assets

Intangible asset balances consisted of the following:

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Amortization expense for the years ended December 31, 2023 and 2022, was $12,996 and $14,706, respectively, which is included in depreciation and amortization in operating expenses in the consolidated statements of operations and comprehensive loss.

The Company tests its license rights, which have indefinite useful lives, for potential impairment on an annual basis. During 2023 and 2022, the Company recorded impairment losses of $4,916 and $11,351, respectively. These losses are included in impairment loss and loss on disposal of assets on the consolidated statements of operations and comprehensive loss.

During 2023, prior to the CGSF/SFNY Divestiture, the Company recognized an impairment loss of $737 on the CGSF-related management agreement to bring the net carrying value to zero. This loss is included in impairment loss and loss on disposal of assets in the consolidated statements of operations and comprehensive loss. Subsequently, the CGSF/SFNY Divestiture resulted in derecognizing the remaining management agreement balance and related accumulated depreciation.

The following table outlines the estimated future annual amortization expense for intangible assets as of December 31, 2023:

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