v3.26.1
Events after the balance sheet date (Details)
4 Months Ended 12 Months Ended
Apr. 29, 2026
CHF (SFr)
SFr / shares
shares
Apr. 29, 2026
USD ($)
$ / shares
shares
Dec. 31, 2025
CHF (SFr)
SFr / shares
shares
Dec. 31, 2024
CHF (SFr)
SFr / shares
shares
Dec. 31, 2023
CHF (SFr)
shares
Events after balance sheet date          
Sale of treasury shares     19,612,752 3,050,665  
Share sale price | SFr / shares     SFr 0.063 SFr 0.08  
Gross proceeds from sale of treasury shares | SFr     SFr 1,228,733 SFr 240,899 SFr 2,350,512
Number of outstanding shares     147,831,814 128,292,969 125,195,393
Number of treasury shares     70,822,682 56,061,527  
Number of outstanding shares benefiting from DSPPP     29,904,690 29,950,268  
ADS          
Events after balance sheet date          
Number of treasury shares     30,000,000    
Sale of treasury shares          
Events after balance sheet date          
Sale of treasury shares 4,068,074 4,068,074      
Share sale price | SFr / shares SFr 0.048        
Gross proceeds from sale of treasury shares | SFr SFr 195,833        
Number of outstanding shares 151,901,337 151,901,337      
Number of treasury shares 66,753,159 66,753,159      
Number of outstanding shares benefiting from DSPPP 29,904,690 29,904,690      
Sale of treasury shares | ADS          
Events after balance sheet date          
Sale of treasury shares 3,422,520 3,422,520      
ADS sale price | $ / shares   $ 7.32      
Share sale price | SFr / shares SFr 0.045        
Gross proceeds from sale of treasury shares SFr 163,160 $ 208,698