Annual report pursuant to section 13 and 15(d)

Stock-Based Compensation (Details)

v2.4.0.8
Stock-Based Compensation (Details) (USD $)
12 Months Ended 1 Months Ended 12 Months Ended 0 Months Ended
Jul. 31, 2013
Jul. 31, 2012
Jul. 31, 2013
Maximum
Jul. 31, 2012
Maximum
Jul. 31, 2013
Minimum
Jul. 31, 2012
Minimum
Jul. 31, 2013
Research and development expense
Jul. 31, 2012
Research and development expense
Jul. 31, 2013
General and administrative expense
Jul. 31, 2012
General and administrative expense
May 31, 2011
2011 Plan
May 31, 2011
2011 Plan
Maximum
May 31, 2011
2011 Plan
Minimum
Jul. 31, 2013
2011 Plan
Employees
Jul. 31, 2012
2011 Plan
Employees
Jul. 31, 2013
2011 Plan
Employees
Maximum
Jul. 31, 2013
2011 Plan
Employees
Minimum
Jul. 31, 2013
2011 Plan
Consultant
Jul. 31, 2012
2011 Plan
Consultant
Jul. 31, 2013
2011 Plan
Consultant
Maximum
Jul. 31, 2012
2011 Plan
Consultant
Maximum
Jul. 31, 2013
2011 Plan
Consultant
Minimum
Jul. 31, 2012
2011 Plan
Consultant
Minimum
Jul. 31, 2013
2011 Plan
Director
Jul. 31, 2012
2011 Plan
Director
Apr. 15, 2013
Amended 2011 Plan
Stock-based compensation                                                    
Number of additional shares authorized                     5,200,000                             3,800,000
Number of shares authorized                                                   9,000,000
Purchase price of incentive stock options as a percentage of its fair value                         100.00%                          
Term of stock options                       10 years   10 years 10 years                 10 years 10 years  
Provisional percentage of outstanding stock owned by stockholders                         10.00%                          
Exercise price as a percentage of fair value of common stock for stockholders who own more than 10% of outstanding stock                         110.00%                          
Options granted to purchase shares 3,015,000 3,260,000                       685,000 1,300,000     2,030,000 1,560,000         300,000 400,000  
Vesting period                             2 years 3 years 2 years     10 years 10 years 3 years 3 years 1 year 1 year  
Exercise price, high end of the range (in dollars per share)                           $ 0.42 $ 0.40     $ 0.35 $ 0.39           $ 0.40  
Exercise price, low end of the range (in dollars per share)                           $ 0.20 $ 0.21     $ 0.18 $ 0.18           $ 0.21  
Exercise price (in dollars per share)                                               $ 0.25    
Expected volatility, minimum (as a percent) 80.32% 85.96%                                                
Expected volatility, maximum (as a percent) 97.85% 125.00%                                                
Risk-free interest rate (as a percent)     1.97% 2.08% 0.31% 0.35%                                        
Expected forfeiture rate (as a percent) 0.00% 0.00%                                                
Expected term     10 years 10 years 3 years 3 years                                        
Forfeiture rate (as a percent) 0.00%                                                  
Stock-based compensation expense recognized $ 452,000 $ 333,000         $ 41,000 $ 89,000 $ 411,000 $ 244,000                                
Option Shares Outstanding                                                    
Balance at the beginning of the period (in shares) 3,175,000                                                  
Granted (in shares) 3,015,000 3,260,000                       685,000 1,300,000     2,030,000 1,560,000         300,000 400,000  
Exercised (in shares) (766,500)                                                  
Forfeited/Cancelled (in shares) (273,500) (85,000)                                                
Balance at the end of the period (in shares) 5,150,000 3,175,000                                                
Weighted-Average Exercise Price                                                    
Balance at the beginning of the period (in dollars per share) $ 0.24                                                  
Granted (in dollars per share) $ 0.22 $ 0.24                                                
Exercised (in dollars per share) $ 0.18                                                  
Forfeited/Cancelled (in dollars per share) $ 0.33 $ 0.40                                                
Balance at the end of the period (in dollars per share) $ 0.23 $ 0.24                                                
Aggregate Intrinsic Value                                                    
Balance at the beginning of the period (in dollars) 24,000                                                  
Granted (in dollars) 232,000                                                  
Exercised (in dollars) 52,000                                                  
Forfeited/Cancelled (in dollars) 9,000                                                  
Balance at the end of the period (in dollars) $ 372,000 $ 24,000