In 2014, the Company adopted the Corbus 2014 Equity Incentive Plan (the “2014 Plan”). Pursuant to the 2014 Plan, the Company’s Board of Directors may grant incentive and nonqualified stock options and restricted stock to employees, officers, directors, consultants and advisors. As of September 30, 2014, there were options to purchase an aggregate of 2,299,382 shares of Common Stock outstanding under the 2014 Plan and 4,550,952 shares are available for future grants. Options issued under the 2014 Plan are exercisable for up to 10 years from the date of issuance.

Share-based compensation

For stock options issued and outstanding for the three and nine months ended September 30, 2014 and 2013, the Company recorded non-cash, stock-based compensation expense of $45,545, $71,957, $1,677 and $4,464, respectively, net of estimated forfeitures.

The fair value of each option award is estimated on the date of grant using the Black-Scholes option pricing model that uses the assumptions noted in the following table. Due to its limited operating history and limited number of sales of its Common Stock, the Company estimated its volatility in consideration of a number of factors, including the volatility of comparable public companies. The Company uses historical data, as well as subsequent events occurring prior to the issuance of the financial statements, to estimate option exercises and employee terminations within the valuation model. The expected term of options granted under the 2014 Plan, all of which qualify as “plain vanilla per SEC Staff Accounting Bulletin 1-7,” is based on the average of the 6.25 years. For non-employee options, the expected term is the contractual term. The risk-free rate is based on the yield of a U.S. Treasury security with a term consistent with the option.

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

A summary of option activity for the nine months ended September 30, 2014 and changes for the nine months ended September 30, 2014 is presented below:

The weighted average grant-date fair value of options granted during the nine months ended September 30, 2014 was $0.38 per share. The total fair value of options that were vested as September 30, 2014 was $307,032. As of September 30, 2014 there was approximately $403,034 of total unrecognized compensation expense, related to non-vested share-based option compensation arrangements. The unrecognized compensation expense is estimated to be recognized over a period of 3.07 years at September, 2014.