Quarterly report pursuant to Section 13 or 15(d)

Consolidated Balance Sheets (Parenthetical)

v3.19.3.a.u2
Consolidated Balance Sheets (Parenthetical) - $ / shares
Nov. 30, 2019
May 31, 2019
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 700,000,000 700,000,000
Common stock, shares issued 399,315,351 399,156,340
Common stock, shares outstanding 329,554,763 329,395,752
Treasury stock, shares (159,011) (159,011)
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 92,100 92,100
Preferred stock, shares outstanding 92,100 92,100
Series C Convertible Preferred Stock    
Preferred stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 20,000 20,000
Preferred stock, shares issued 7,788 3,246
Preferred stock, shares outstanding 7,788 3,246