Intangible Assets

6 Months Ended

Jun. 30, 2017

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

4. Intangible Assets

Intangible assets consist of the following (in thousands):

	As of
	June 30, 2017			December 31, 2016
Patents issued	$	4,388		$	4,892
Patents pending		200			385
Trademarks		40			40
Total intangible assets		4,628			5,317
Less patent amortization		(1,419	)		(1,316	)
Intangible assets, net	$	3,209		$	4,001

The following table presents patent amortization expense included in the Condensed Consolidated Statement of Operations (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Amortization expense	$	81	$	117	$	166	$	264