Quarterly report pursuant to Section 13 or 15(d)

Consolidated Statement of Changes in Stockholders' (Deficit) Equity

v3.22.1
Consolidated Statement of Changes in Stockholders' (Deficit) Equity - USD ($)
shares in Thousands, $ in Thousands
Preferred Stock
Common Stock
Private Warrant Exchange [Member]
Common Stock
Private Equity Offering
Common Stock
Treasury Stock
Additional Paid-in Capital
Private Warrant Exchange [Member]
Additional Paid-in Capital
Private Equity Offering
Additional Paid-in Capital
Accumulated Deficit
Private Warrant Exchange [Member]
Private Equity Offering
Total
Beginning balance at May. 31, 2020       $ 519       $ 372,301 $ (375,301)     $ (2,481)
Beginning balance, shares at May. 31, 2020 109     519,261 286              
Issuance of stock for convertible note repayment, value       $ 2       9,535       9,537
Issuance of stock for convertible note, shares       2,119                
Issuance of legal settlement, warrants, value       $ 4       (4)        
Issuance of legal settlement, warrants, shares       4,000                
Exercise of stock option, value               (39)       (39)
Exercise of stock option, shares       100                
Stock issued via offering, tender or placement, value   $ 17       $ 7,787       $ 7,804    
Stock issued via offering, tender or placement, shares   16,544                    
Conversion of preferred stock to common stock, shares (5)     50                
Warrant exercises, value       $ 28       12,662       12,690
Warrant exercises, shares       27,928                
Inducement interest expense related to private warrant exchange           3,345       3,345    
Dividend declared and paid                 (243)     (243)
Dividends accrued on preferred stock                 (420)     (420)
Stock-based compensation               2,865       2,865
Offering costs, stock and warrants           (364)       (364)    
Stock issued for incentive compensation and tendered for income tax               828       828
Stock issued for incentive compensation and tendered for income tax , shares       323 156              
Net loss                 (30,832)     (30,832)
Ending balance at Aug. 31, 2020       $ 570       408,994 (406,796)     2,768
Ending balance, shares at Aug. 31, 2020 104     570,325 442              
Beginning balance at May. 31, 2020       $ 519       372,301 (375,301)     (2,481)
Beginning balance, shares at May. 31, 2020 109     519,261 286              
Net loss                       (111,463)
Ending balance at Feb. 28, 2021       $ 609       471,849 (488,253)     (15,795)
Ending balance, shares at Feb. 28, 2021 96     609,420 442              
Beginning balance at May. 31, 2020       $ 519       372,301 (375,301)     (2,481)
Beginning balance, shares at May. 31, 2020 109     519,261 286              
Ending balance at May. 31, 2021       $ 626       512,796 (534,440)     (21,018)
Ending balance, shares at May. 31, 2021 96     626,123 443              
Beginning balance at Aug. 31, 2020       $ 570       408,994 (406,796)     2,768
Beginning balance, shares at Aug. 31, 2020 104     570,325 442              
Issuance of stock for convertible note repayment, value       $ 4       11,549       11,553
Issuance of stock for convertible note, shares       4,293                
Exercise of stock option, value               10       10
Exercise of stock option, shares       10                
Stock issued via offering, tender or placement, value   $ 13 $ 1     4,583 $ 999     4,596 $ 1,000  
Stock issued via offering, tender or placement, shares   12,480 667                  
Warrant exercises, value       $ 2       1,737       1,739
Warrant exercises, shares       2,504                
Inducement interest expense related to private warrant exchange           4,217       4,217    
Dividends accrued on preferred stock                 (415)     (415)
Stock-based compensation               3,423       3,423
Net loss                 (35,425)     (35,425)
Ending balance at Nov. 30, 2020       $ 590       435,512 (442,636)     (6,534)
Ending balance, shares at Nov. 30, 2020 104     590,279 442              
Issuance of stock for convertible note repayment, value       $ 4       20,500       20,504
Issuance of stock for convertible note, shares       4,013                
Exercise of stock option, value       $ 2       1,778       1,780
Exercise of stock option, shares       2,471                
Stock issued via offering, tender or placement, value   $ 6       3,461       3,467    
Stock issued via offering, tender or placement, shares   5,939                    
Conversion of preferred stock to common stock, shares (8)     80                
Warrant exercises, value       $ 7       3,432       3,439
Warrant exercises, shares       6,638                
Inducement interest expense related to private warrant exchange           5,360       5,360    
Dividends accrued on preferred stock                 (411)     (411)
Stock-based compensation               1,937       1,937
Offering costs, stock and warrants           (131)       (131)    
Net loss                 (45,206)     (45,206)
Ending balance at Feb. 28, 2021       $ 609       471,849 (488,253)     $ (15,795)
Ending balance, shares at Feb. 28, 2021 96     609,420 442              
Issuance of common stock upon vesting of stock based compensation awards, shares                       400
Ending balance at May. 31, 2021       $ 626       512,796 (534,440)     $ (21,018)
Ending balance, shares at May. 31, 2021 96     626,123 443              
Issuance of stock for convertible note repayment, value       $ 12       18,483       18,495
Issuance of stock for convertible note, shares       11,816                
Issuance of legal settlement, warrants, value               1,744       1,744
Exercise of stock option, value               189       189
Exercise of stock option, shares       300                
Stock issued via offering, tender or placement, value   $ 1 $ 3     774 2,869     775 $ 2,872  
Stock issued via offering, tender or placement, shares   1,327 2,872                  
Warrant exercises, value       $ 1       502       503
Warrant exercises, shares       668                
Inducement interest expense related to private warrant exchange           528       528    
Dividends accrued on preferred stock                 (420)     (420)
Stock-based compensation               2,597       2,597
Stock issued for incentive compensation and tendered for income tax       $ 1       (1)        
Stock issued for incentive compensation and tendered for income tax , shares       1,014                
Net loss                 (31,458)     (31,458)
Ending balance at Aug. 31, 2021       $ 644       540,481 (566,318)     (25,193)
Ending balance, shares at Aug. 31, 2021 96     644,120 443              
Beginning balance at May. 31, 2021       $ 626       512,796 (534,440)     (21,018)
Beginning balance, shares at May. 31, 2021 96     626,123 443              
Stock issued via offering, tender or placement, value                   5,400    
Conversion of preferred stock to common stock                       2
Warrant exercises, shares                     23,500  
Net loss                       (100,390)
Ending balance at Feb. 28, 2022       $ 713       612,905 (636,078)     (22,460)
Ending balance, shares at Feb. 28, 2022 35     713,730 443              
Beginning balance at Aug. 31, 2021       $ 644       540,481 (566,318)     (25,193)
Beginning balance, shares at Aug. 31, 2021 96     644,120 443              
Issuance of stock for convertible note repayment, value       $ 8       11,505       11,513
Issuance of stock for convertible note, shares       8,162                
Exercise of stock option, value               200       200
Exercise of stock option, shares       210                
Stock issued via offering, tender or placement, value   $ 7 $ 25     4,608 27,282     4,615 $ 27,307  
Stock issued via offering, tender or placement, shares   6,593 25,178                  
Conversion of preferred stock to common stock       $ 1               1
Conversion of preferred stock to common stock, shares (60)     600                
Warrant exercises, value       $ 1       532       533
Warrant exercises, shares       963                
Inducement interest expense related to private warrant exchange           $ 4,704       $ 4,704    
Dividend declared and paid               17 (17)      
Dividend declared and paid, shares       35                
Dividends accrued on preferred stock                 (414)     (414)
Stock-based compensation               2,060       2,060
Offering costs, stock and warrants             (1,418)       (1,418)  
Net loss                 (36,604)     (36,604)
Ending balance at Nov. 30, 2021       $ 686       589,971 (603,353)     (12,696)
Ending balance, shares at Nov. 30, 2021 36     685,861 443              
Issuance of stock for convertible note repayment, value       $ 17       12,048       12,065
Issuance of stock for convertible note, shares       17,132                
Stock issued via offering, tender or placement, value     $ 7       $ 3,545       $ 3,552  
Stock issued via offering, tender or placement, shares     6,860             7,900    
Conversion of preferred stock to common stock       $ 2       (2)        
Conversion of preferred stock to common stock, shares (1)     2,200                
Warrant exercises, shares       11                
Modification of previously issued equity, value       $ 1       953       954
Modification of previously issued equity, shares       1,179                
Dividend declared and paid               243       243
Dividend declared and paid, shares       487                
Dividends accrued on preferred stock                 (397)     (397)
Finance charges related to warrant issuance for surety bond backstop agreement               6,585       6,585
Stock-based compensation               (438)       (438)
Net loss                 (32,328)     (32,328)
Ending balance at Feb. 28, 2022       $ 713       $ 612,905 $ (636,078)     $ (22,460)
Ending balance, shares at Feb. 28, 2022 35     713,730 443