Segment information (Tables)

12 Months Ended

Dec. 31, 2022

Segment information

Summary of collaboration revenues by destination

	Year ended December 31,
	2022		2021		2020
	(Euro, in thousands)
United States of America	€	414,129	€	467,978	€	472,445
Europe		3,552		2,114		5,605
Total collaboration revenues	€	417,681	€	470,093	€	478,051

Summary of revenues by major customers

	Year ended December 31,
	2022			2021			2020
	(Euro in thousands)		%	(Euro, in thousands)		%	(Euro in thousands)		%
Gilead:
United States of America	€	414,129	100%	€	467,978	100%	€	472,445	99%
Europe		1,452	0%		2,071	0%		1,460	0%
AbbVie:
Europe		—	0%		—	0%		(52)	0%
Novartis:
Europe		56	0%		—	0%		4,125	1%
Total revenues from major customers	€	415,637	100%	€	470,049	100%	€	477,978	100%

Schedule of non-current assets other than financial instruments, deferred tax assets, post-employment benefit assets, and rights arising under insurance contracts by location

	December 31,
	2022		2021		2020
		(Euro, in thousands)
Belgium	€	72,087	€	98,295	€	113,524
France		20,397		21,051		18,398
The Netherlands		255,461		66,621		28,210
Switzerland		4,962		7,181		7,668
Spain		3,037		3,029		2,755
United States of America		12,729		136		372
Other		1,747		1,302		16
Total non-current assets	€	370,420	€	197,615	€	170,943