Intangible Assets

12 Months Ended

Dec. 31, 2020

3. Intangible Assets

Intangible assets as of December 31, 2020, and 2019 consisted of the following:

	Estimated useful lives				As of December 31,
	(in years)				2020			2019
Tradename		5	to	7	$	555		$	555
Patents and technological know-how			10			25,427			18,494
Proprietary software		3	to	15		2,981			2,981
Other		3	to	5		323			323
Total intangible assets, gross						29,286			22,353
Accumulated amortization						(10,038	)		(8,344	)
Total intangible assets, net					$	19,248		$	14,009

Patents and technological know-how include capitalized legal expenses, net of amortization of $16,582 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, 2020 and 2019, amortization of these intangible assets were $1,694 and $1,402 respectively.

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

Years ending December 31,
2021	$	1,959
2022		1,959
2023		1,952
2024		1,689
2025		1,628
Thereafter		10,061
Total	$	19,248