Quarterly report pursuant to Section 13 or 15(d)

Consolidated Balance Sheets (Parenthetical)

v3.21.4
Consolidated Balance Sheets (Parenthetical) - $ / shares
Nov. 30, 2021
May 31, 2021
Preferred stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 5,000,000 5,000,000
Common stock, par value $ 0.001 $ 0.001
Common stock, shares authorized 1,000,000,000 1,000,000,000
Common stock, shares issued 685,861,000 626,123,000
Common stock, shares outstanding 685,418,000 625,680,000
Treasury stock, shares 443,000 443,000
Treasury Stock    
Common stock, par value $ 0.001 $ 0.001
Series B Convertible Preferred Stock    
Preferred stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 400,000 400,000
Preferred stock, shares issued 19,000 79,000
Preferred stock, shares outstanding 19,000 79,000
Series C Convertible Preferred Stock    
Preferred stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 8,203 8,000
Preferred stock, shares issued 8,000 8,000
Preferred stock, shares outstanding 8,203 8,000
Series D Convertible Preferred Stock    
Preferred stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 11,737 12,000
Preferred stock, shares issued 9,000 9,000
Preferred stock, shares outstanding 9,000 9,000