Quarterly report pursuant to Section 13 or 15(d)

Stock Options (Tables)

v3.8.0.1
Stock Options (Tables)
3 Months Ended
Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Summary of Assumptions Used Principally in Determining Fair Value of Options Granted

The weighted average assumptions used principally in determining the fair value of options granted to employees were as follows:

 

    Three Months Ended March 31,  
    2018     2017  
Risk free interest rate     2.34 %     2.17 %
Expected dividend yield     0 %     0 %
Expected term in years     6.25       6.35  
Expected volatility     88.1 %     85.8 %
Estimated forfeiture rate     5 %     5 %

Summary of Option Activity

A summary of option activity for the three months ended March 31, 2018 is presented below:

 

                Weighted        
                Average        
          Weighted     Remaining        
          Average     Contractual     Aggregate  
Options   Shares     Exercise Price     Term in Years     Intrinsic Value  
Outstanding at December 31, 2017     7,844,966     $ 3.75                  
Granted     1,574,500       8.32                  
Exercised     (36,465 )     4.30                  
Forfeited     (40,417 )     7.28                  
Outstanding at March 31, 2018     9,342,584     $ 4.50       7.85     $ 29,325,265  
Vested at March 31, 2018     5,049,555     $ 2.41       6.93     $ 24,544,006