v3.26.1
Income tax (Details) - EUR (€)
€ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]      
Loss before tax € (354,116) € (183,899) € (109,819)
Theoretical tax rate 25.00% 25.00% 25.00%
Tax benefit at theoretical rate € 88,529 € 45,975 € 27,455
Tax credits 873 1,584 1,794
Permanent differences 3,967 (16,275) 478
Other permanent differences (6,905) (860) (975)
Temporary differences (36) (34) (30)
Tax rate differences 138 100 83
Non recognition of deferred tax assets related to tax losses and temporary differences (86,589) (30,569) (28,930)
Impairment loss of deferred tax asset   (234) (481)
Actual income tax benefit (22) (313) (607)
Current taxes (124) (305) (62)
Deferred taxes € 102 € (8) € (545)
Effective tax rate 0.04% 0.17% 0.06%
Deferred tax asset € 191 € 217 € 225
Tax losses      
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]      
Deferred tax asset 0 € 0 € 0
Forecast      
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]      
Current taxes 0    
Inventiva S.A      
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]      
Current taxes € 0