4. Goodwill and other identifiable intangible assets

Goodwill

As a result of a decrease in Company’s public stock price that caused the Company's market capitalization to fall below its carrying amount (stockholders' equity) during July 2023 and noted by management to be more than temporary as the quarter progressed, a quantitative analysis was required to be performed during the quarter ended September 30, 2023. The Company used a discounted cash flow analysis based on Level 3 inputs and determined that the goodwill carrying amount exceeded its fair value and, as such, an impairment charge of $32,894 was incurred in the quarter ended September 30, 2023. Accumulated impairment losses were $32,894 for the year ended December 31, 2023.

The Company performed an assessment of qualitative factors and determined that no events or circumstances existed that would lead to a determination that it is more likely than not that the fair value of indefinite-lived assets were less than the carrying amount. As a result of the TAV technology intangible asset disposal, a quantitative analysis was required to be performed as of December 31, 2022 and concluded that there was no impairment.

Intangible assets

There were no impairment losses related to the Company’s intangible assets as of December 31, 2023 and 2022. Amortization expense for intangible assets for the years ended December 31, 2023, 2022 and 2021 was as follows:

Intangible assets as of December 31, 2023 and 2022 consisted of the following: