4. Employee Stock-Based Compensation

Stock Option Grant

On February 11, 2014, our board of directors granted 1,268,000 stock options to employees under our 2007 Incentive Plan and 549,000 stock options to employees under our 2005 Incentive Plan. All the awards vest at 25% per year at each anniversary of the grant date over four years. The exercise price for the options was $7.67 per share, which was the closing stock price on the grant date. The weighted average grant date fair value of the options was $5.71 and was determined using the Black-Scholes option-pricing model with the following weighted average assumptions:

Expected life	5.8 years
Expected volatility	92.1%
Expected dividend yield	0.00%
Risk-free rate	1.83%

The expected life represents the period of time the options are expected to be outstanding. We used the simplified method for determining the expected life assumption due to limited historical exercise experience on our stock options. The expected volatility is based on the historical volatility of our common stock over the most recent period equal to the expected life of the option. The expected dividend yield is based on our history of not paying regular dividends in the past and our current intention to not pay regular dividends in the foreseeable future. The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant and has a term equal to the expected life of the options.

2014 Incentive Plan

Under our 2014 Incentive Plan (“2014 Plan”), the Company is authorized to grant awards in the form of incentive stock options, non-qualified stock options, restricted stock shares, restricted stock units, other common stock-based awards and cash-based awards. The maximum number of common shares reserved for the grant of awards under the 2014 Plan is 5.0 million, subject to adjustment as provided by the 2014 Plan. All 5.0 million shares under the Plan may be made subject to options, stock appreciation rights (“SARs”), or stock-based awards. Stock options and SARs granted under the 2014 Plan may not have a term exceeding 10 years from the date of grant. The 2014 Plan also provides that all awards will become fully vested and/or exercisable upon a change in control (as defined in the 2014 Plan) if those awards (i) are not assumed or equitably substituted by the surviving entity or (ii) have been assumed or equitably substituted by the surviving entity, and the grantee’s employment is terminated under certain circumstances. Other specific terms for awards granted under the 2014 Plan shall be determined by our Compensation Committee (or the board of directors if so determined by the board of directors). Awards granted under the 2014 Plan generally vest ratably over a four year period. As of June 30, 2014, 3.7 million shares were available for issuance under the 2014 Plan.

Restricted Stock Unit Grant

On June 16, 2014, our board of directors granted 1,303,000 restricted stock units to employees under our 2014 Incentive Plan and 513,000 restricted stock units to employees under our 2007 Incentive Plan. All the awards vest at 25% per year and vesting will coincide with the vesting of the stock options granted on February 11, 2014 over the next four years. The grant date fair value for the restricted stock units was $7.52 per share, which was the closing stock price on the grant date.