Intangible Assets

12 Months Ended

Dec. 31, 2019

Intangible Assets

Intangible Assets

3. Intangible Assets

Intangible assets as of December 31, 2019, and 2018 consisted of the following:

	Estimated useful lives				As of December 31,
	(in years)				2019			2018
Tradename		5	to	7	$	555		$	555
Patents and technological know-how			10			18,494			13,377
Proprietary software		3	to	15		2,981			2,981
Other		3	to	5		323			323
Total intangible assets, gross						22,353			17,236
Accumulated amortization						(8,344	)		(6,987	)
Total intangible assets, net					$	14,009		$	10,249

Intangible assets include capitalized legal expenses, net of amortizationof $11,040 million 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 Note8 - Commitments and Contingenciesfor additional information. 

During the years ended December 31, 2019 and 2018, amortization of these intangible assets were$1,402 and $1,093 respectively.

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

Years ending December 31,
2020	$	1,398
2021		1,396
2022		1,396
2023		1,389
2024		1,125
Thereafter		7,305
Total	$	14,009