Intangible assets

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible assets, net of accumulated amortization, are summarized as follows (in thousands):


	As of December 31,						As of December 31,
	2021						2020
	Cost		Accumulated amortization		Net		Cost		Accumulated amortization		Net
Developed technology	$	30,100	$	(28,218)	$	1,882	$	30,100	$	(24,456)	$	5,644
In-licensed rights	8,500		(490)		8,010		—		—		—
Total	$	38,600	$	(28,708)	$	9,892	$	30,100	$	(24,456)	$	5,644

Amortization expense for intangible assets was $4.3 million, $3.8 million, and $3.8 million for the years ended December 31, 2021, 2020 and 2019, respectively.

Developed technology

The Company's developed technology was obtained through the acquisition in 2014 of Pregenen, a privately-held biotechnology company includes gene editing and cell signaling technology with a broad range of potential therapeutic applications. The gene editing platform intangible asset is being amortized on a straight-line basis over its expected useful life of approximately eight years from the date of the acquisition.

In-licensed rights

In-licensed rights consist of capitalized milestone payments made to third parties upon receiving regulatory approval of ABECMA in the U.S. The in-licensed rights are being amortized on a straight-line basis over the remaining life of the related patents of approximately twelve years, as the life of the related patents reflects the expected time period that the Company will benefit from the in-licensed rights.

The following table summarizes the estimated future amortization for intangible assets for the next five years and thereafter (in thousands):


	As of December 31, 2021
2022	$	2,590
2023	708
2024	708
2025	708
2026	708
2027 and thereafter	4,470
Total	$	9,892