Intangible Assets

12 Months Ended

Dec. 31, 2021

Intangible Assets

Intangible Assets

3. Intangible Assets

Intangible assets as of December 31, 2021 and 2020 consisted of the following:

	Estimated useful lives				As of December 31,
	(in years)				2021			2020
Tradename		5	to	7	$	555		$	555
Patents and technological know-how			10			33,553			25,427
Proprietary software		3	to	15		2,981			2,981
Other		3	to	5		323			323
Total intangible assets, gross						37,412			29,286
Accumulated amortization						(12,326	)		(10,038	)
Total intangible assets, net					$	25,086		$	19,248

Patents and technological know-how include capitalized legal expenses, net of amortization of $22,637 related to our defense of patents from infringement by our competitors. Legal expenses have been capitalized upon satisfaction of two conditions: (a) a determination being made that a successful defense of this litigation is probable, and (b) that the monetary benefits arising out of such successful defense will be in excess of the costs for the defense. Please refer to Note 8 - Commitments and Contingencies for additional information. 

During the years ended December 31, 2021 and 2020, amortization of these intangible assets were $2,288 and $1,694 respectively.

The estimated future amortization expense of intangible assets is as follows:

Years ending December 31,
2022	$	2,683
2023		2,677
2024		2,413
2025		2,351
2026		2,351
Thereafter		12,611
Total	$	25,086