v3.25.2
Share capital (Details) - CHF (SFr)
 1 Months Ended 6 Months Ended
Feb. 20, 2024
Dec. 31, 2023
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Share capital          
Number of shares at beginning of period          
Number of shares at beginning of period     128,292,969 125,195,393  
Sale of treasury shares     12,898,903 3,050,665  
Movement of shares under liquidity agreement     6,268 10,500  
Acquisition of shares forfeited from DSPPP     (5,848) (8,539)  
Number of shares at end of period     (43,162,204) (56,106,477)  
Number of shares at end of period   125,195,393 141,192,292 128,248,019  
Number of shares reclassed as treasury shares under IFRS 2     (29,944,420) (29,950,268)  
Number of shares including IFRS 2 shares     111,247,872 98,297,751  
Treasury shares     SFr 738,489   SFr 869,708
Share sale price     SFr 0.06 SFr 0.077  
Gross proceeds from sale of treasury shares     SFr 777,546 SFr 235,257  
Number of shares registered in commercial register during period 6,120,000        
Treasury shares sold not under sale agency agreement          
Share capital          
Sale of treasury shares     10,966,666    
Share sale price     SFr 0.06    
Number of warrants granted     2,741,666    
Exercise price of granted warrants     SFr 0.06    
Exercise period of warrants granted     5 years    
Value of warrants     SFr 65,609    
Treasury shares sold under sale agency agreement          
Share capital          
Sale of treasury shares     1,932,237    
Share sale price     SFr 0.06    
Gross proceeds from sale of treasury shares     SFr 119,548    
Kepler | Treasury Shares Reserve          
Share capital          
Treasury shares     110,354   116,622
Kepler | Other financial assets          
Share capital          
Treasury shares     SFr 6,994   SFr 6,496
Common shares          
Share capital          
Number of shares at beginning of period     184,354,496 184,354,496  
Number of shares at end of period   184,354,496 184,354,496 184,354,496  
Number of common shares including IFRS 2 shares     184,354,496 184,354,496  
Exercise of pre-funded warrants   6,120,000      
Share capital as registered in commercial register   SFr 1,782,344.96      
Number of shares registered in commercial register   178,234,496      
Treasury shares          
Share capital          
Number of shares at beginning of period     (56,061,527) (59,159,103)  
Sale of treasury shares     12,898,903 3,050,665  
Movement of shares under liquidity agreement     6,268 10,500  
Acquisition of shares forfeited from DSPPP     (5,848) (8,539)  
Number of shares at end of period   (59,159,103) (43,162,204) (56,106,477)  
Number of shares reclassed as treasury shares under IFRS 2     (29,944,420) (29,950,268)  
Number of shares including IFRS 2 shares     (73,106,624) (86,056,745)