
	Year Ended December 31,
(in thousands of $)	2025		20241)		20231)
Research and development incentives	$	62,503	$	46,106	$	27,815
Payroll tax rebates		19,061		11,855		11,925
Collaboration revenue		2,166		4,348		35,533
Change in fair value on non-current financial assets		11,581		3,834		—
Other operating income		1,423		13		2,538
Total other operating income	$	96,734	$	66,156	$	77,811

1)Comparative figures have been aligned with the presentation adopted in the current year.

For the year ended December 31, 2025, the collaboration revenue was generated under the agreement with Zai Lab. This

note should be read alongside ‘‘Note 2.18 — Other operating income - Collaboration and license agreements’’.

The Company has accounted for tax incentives following a research and development tax incentive scheme in Belgium

according to which the incentive will be refunded after a 5 years period, if not offset against the current tax payable over

The Company accounted for payroll tax rebates as a reduction in withholding income taxes for its highly qualified

In April 2016, the Company entered into the AbbVie Collaboration Agreement to develop and commercialize

ARGX-115 (ABBV-151). In October 2023, the Company achieved the second development milestone upon initiation of

Subject to the continuing progress of ARGX-115 (ABBV-151) by AbbVie, the Company is eligible to receive future

development, regulatory and commercial milestone payments in aggregate amounts of up to $50 million, $190 million

and $325 million, respectively, as well as tiered royalties on sales at percentages ranging from the mid-single digits to