The following schedule represents the gross carrying amount and accumulated amortization of intangible assets as of March 31, 2025 and December 31, 2024. Product rights and trademarks are amortized over the lesser of the useful life ranging from 10 to 25 years, or the patent life. Customer lists are amortized over their expected useful lives of nine to ten years. The amortization expense is included in operating expenses on the consolidated statements of operations.


	2025						2024
	Gross		Accumulated Amortization		Net Book Value		Gross		Accumulated Amortization		Net Book Value
Product rights and patents	$	261,017	$	140,522	$	120,495	$	260,928	$	138,090	$	122,838
Trademarks		38,579		14,786		23,793		38,475		14,375		24,100
Customer lists		12,144		8,764		3,380		11,874		8,315		3,559
Total intangibles assets	$	311,740	$	164,072	$	147,668	$	311,277	$	160,780	$	150,497

Domestic intangible assets		172,805		103,918		68,887		172,755		102,347		70,408
International intangible assets		138,935		60,154		78,781		138,522		58,433		80,089
Total intangibles assets - domestic and international	$	311,740	$	164,072	$	147,668	$	311,277	$	160,780	$	150,497

The following schedule represents intangible assets activity for the three months ended March 31, 2025:


	Amount
Intangible assets at January 1, 2025	$	150,497
Additions during Q1 2025		27
Impact of movement in exchange rates		210
Amortization expense		(3,066	)
Intangible assets at March 31, 2025	$	147,668

Goodwill at January 1, 2025	$	19,701
Impact of movement in exchange rates		590
Goodwill at March 31, 2025	$	20,291

During the three months ended March 31, 2025, and 2024, amortization expense was $3,066 and $3,274, respectively.