v3.25.2
Share-based payments - Assumptions used to determine the fair value of option grants (Details)
9 Months Ended
May 31, 2025
Y
$ / shares
May 27, 2020  
Share-based payments  
Exercise price $ 4,995
Market Price $ 4,995
Expected volatility 84.00%
Risk-free interest rate 0.40%
Expected life | Y 5
May 27, 2020  
Share-based payments  
Exercise price $ 3,753
Market Price $ 4,995
Expected volatility 84.00%
Risk-free interest rate 0.40%
Expected life | Y 5
October 23, 2020  
Share-based payments  
Exercise price $ 4,995
Market Price $ 4,995
Expected volatility 97.00%
Risk-free interest rate 0.40%
Expected life | Y 5
November 24, 2020  
Share-based payments  
Exercise price $ 21,991.5
Market Price $ 17,590.5
Expected volatility 101.00%
Risk-free interest rate 0.40%
Expected life | Y 5
November 24, 2020  
Share-based payments  
Exercise price $ 7,668
Market Price $ 7,722
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 4
February 23, 2021  
Share-based payments  
Exercise price $ 21,262.5
Market Price $ 20,317.5
Expected volatility 103.00%
Risk-free interest rate 0.60%
Expected life | Y 5
May 14, 2021  
Share-based payments  
Exercise price $ 7,668
Market Price $ 7,722
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 3
July 14, 2021  
Share-based payments  
Exercise price $ 12,487.5
Market Price $ 12,163.5
Expected volatility 105.00%
Risk-free interest rate 0.70%
Expected life | Y 5
September 21, 2021  
Share-based payments  
Exercise price $ 11,947.5
Market Price $ 11,583
Expected volatility 106.00%
Risk-free interest rate 0.90%
Expected life | Y 5
January 22, 2022  
Share-based payments  
Exercise price $ 7,627.5
Market Price $ 7,452
Expected volatility 107.00%
Risk-free interest rate 1.50%
Expected life | Y 5
November 30, 2022  
Share-based payments  
Exercise price $ 8,221.5
Market Price $ 8,221.5
Expected volatility 107.00%
Risk-free interest rate 3.10%
Expected life | Y 5
December 1, 2022  
Share-based payments  
Exercise price $ 7,870.5
Market Price $ 7,870.5
Expected volatility 107.00%
Risk-free interest rate 3.00%
Expected life | Y 5
March 22, 2023  
Share-based payments  
Exercise price $ 7,776
Market Price $ 6,939
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 2
March 25, 2023  
Share-based payments  
Exercise price $ 7,789.5
Market Price $ 7,060.5
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 3
March 25, 2023  
Share-based payments  
Exercise price $ 7,789.5
Market Price $ 7,060.5
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 4
April 20, 2023  
Share-based payments  
Exercise price $ 7,816.5
Market Price $ 7,114.5
Expected volatility 75.00%
Risk-free interest rate 3.60%
Expected life | Y 5
December 29, 2023  
Share-based payments  
Exercise price $ 6,129
Market Price $ 1,998
Expected volatility 76.00%
Risk-free interest rate 3.10%
Expected life | Y 5
January 26, 2024  
Share-based payments  
Exercise price $ 1,390.5
Market Price $ 1,458
Expected volatility 76.00%
Risk-free interest rate 3.50%
Expected life | Y 5