Note 5 – Intangible Assets

Intangible assets subject to amortization at December 31 were as follows:

December 31, 2017
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	11,823	$	(9,154	)	$	(242	)	$	2,427
Software license	3 years		1,212		(1,149	)		(63	)		-
Developed product technology	2-10 years		154,795		(53,925	)		(6,219	)		94,651
Customer relationships	12 years		62,093		(19,319	)		(1,650	)		41,124
Other	4 years		4,610		(4,512	)		(75	)		23
Total amortized intangible assets			234,533		(88,059	)		(8,249	)		138,225
Intangible assets with indefinite lives
In process research and development	Indefinite		8,914		-			-			8,914
Trademarks and trade names	Indefinite		10,303		-			(997	)		9,306
Total Intangible assets with indefinite lives			19,217		-			(997	)		18,220
Total intangible assets		$	253,750	$	(88,059	)	$	(9,246	)	$	156,445

December 31, 2016
Intangible Assets	Useful life	Gross Carrying Amount		Accumulated Amortization			Currency Exchange			Net
Amortized intangible assets
Patents	5-15 years	$	11,823	$	(8,431	)	$	(255	)	$	3,137
Software license	3 years		1,212		(1,149	)		(63	)		-
Developed product technology	2-10 years		153,009		(41,416	)		(6,299	)		105,294
Customer relationships	12 years		62,093		(13,915	)		(1,750	)		46,428
Other	4 years		4,610		(4,336	)		(75	)		199
Total amortized intangible assets			232,747		(69,247	)		(8,442	)		155,058
Intangible assets with indefinite lives
In process research and development	Indefinite		10,700		-			-			10,700
Trademarks and trade names	Indefinite		10,303		-			(1,185	)		9,118
Total Intangible assets with indefinite lives			21,003		-			(1,185	)		19,818
Total intangible assets		$	253,750	$	(69,247	)	$	(9,627	)	$	174,876

Amortization expense related to intangible assets subject to amortization was $18.8 million, $20.5 million and $8.6 million for the years ended December 31, 2017, 2016 and 2015, respectively.

Amortization of intangible assets is as follows:

2018	$	18,003
2019		17,498
2020		15,472
2021		14,775
2022		13,956
2023 and thereafter		58,521
Total	$	138,225