Note 6 Intangible Assets

Intangible assets other than goodwill at December 31, 2013 and December 31, 2012 are as follows:


	2013						2012
(in thousands)	Gross		Accumulated Amortization		Net		Gross		Accumulated Amortization		Net		Useful Life (in years)	Weighted Average Useful Life Remaining (in years)
Intangible assets with finite lives:
Licenses	$	5,875	$	(5,875)	$	—	$	5,875	$	(5,875)	$	—
Patent costs		21,545		(5,960)		15,585		27,635		(14,047)		13,588	6 - 19	3
Acquired technology		30,095		(13,615)		16,480		26,262		(11,852)		14,410	5 - 10	5
Internally developed software		18,097		(12,863)		5,234		17,847		(11,424)		6,423	5	<1
Customer relationships		95,793		(18,283)		77,510		60,329		(7,754)		52,575	5 - 20	5
Non-compete agreements		16,848		(6,666)		10,182		14,051		(3,836)		10,215	3 - 11	3
Trade names		9,302		(2,211)		7,091		5,814		(723)		5,091	2 - 10	3
Other		11,598		(4,081)		7,517		6,356		(3,051)		3,305	<1 - 7	2
Intangible assets with indefinite lives:
Trademarks		2,110		—		2,110		2,770		—		2,770	N/A	N/A
Total intangible assets	$	211,263	$	(69,554)	$	141,709	$	166,939	$	(58,562)	$	108,377	<1 - 20	4

During 2013, 2012 and 2011, the Company capitalized $1,648, $729 and $336, respectively, for costs incurred to acquire, develop and extend patents in the United States and various other countries. Amortization of such previously capitalized patent costs was $250 in 2013, $215 in 2012 and $237 in 2011.

At December 31, 2013, the gross acquired technology balance increased by $3,833, to $30,095, compared to $26,262 in 2012, due to technology from acquisitions and foreign currency exchange effects. The related accumulated amortization increased by $1,763, net of foreign currency exchange impacts.

The Company had $109,644 and $80,276 of other net intangible assets, consisting of internally developed software, non-compete agreements, customer relationships and trade names and other intangibles from acquisitions, as of December 31, 2013 and 2012, respectively. Internally developed software also includes certain software costs that relate to developed software the Company obtained through acquisitions. Acquisition activities during the year ended December 31, 2013 yielded $51,930 of other intangible assets compared to $65,957 in 2012. Amortization expense related to such intangible assets was $20,447, $12,573 and $4,588 for the years ended December 31, 2013, 2012 and 2011, respectively. Amortization of these intangible assets is calculated on a straight-line basis over periods ranging from less than one year to twenty years.

Annual amortization expense for intangible assets is expected to be $22,120 in 2014, $20,302 in 2015, $18,119 in 2016, $16,109 in 2017 and $13,616 in 2018.