Intangible assets, net

3 Months Ended

Mar. 31, 2013

Intangible assets [Abstract]

Intangible assets

6. Intangible assets, net

Intangible assets as of March 31, 2013 and December 31, 2012, respectively, comprise the following (in thousands):

	March 31, 2013							December 31, 2012
	Gross carrying amount		Accumulated amortization			Net carrying amount		Gross carrying amount		Accumulated amortization			Net carrying amount
Licensed intellectual property	$	3,942	$	(1,376	)	$	2,566	$	3,144	$	(1,312	)	$	1,832

Licenses have a weighted average remaining amortization period of 6.47 years as of March 31, 2013. Amortization expense for intangible assets amounted to $64,000 and $40,000 for the three months ended March 31, 2013 and 2012, respectively. Estimated future amortization expense for these licenses (assuming no impairment charges) is as follows (in thousands):

Years Ending March 31,	Amount
2014	$	311
2015		311
2016		311
2017		306
2018		302
Thereafter		1,025
Total	$	2,566