Stockholder's Equity

6 Months Ended

Jun. 30, 2018

Equity [Abstract]

Stockholders' Equity

6. Stockholders’ Equity

Equity Incentive Plans

The Company’s Board of Directors, or Board, and stockholders previously approved the 2014 Equity Incentive Plan, or the 2014 Plan, which became effective on March 21, 2014.  As of June 30, 2018, the total number of shares of common stock available for issuance under the 2014 Plan was approximately 2,355,000.  Unless the Board provides otherwise, beginning on January 1, 2015, and continuing until the expiration of the 2014 Plan, the total number of shares of common stock available for issuance under the 2014 Plan will automatically increase annually on January 1 by 4.5% of the total number of issued and outstanding shares of common stock as of December 31 of the immediately preceding year. As of June 30, 2018, approximately 4,391,000 shares of common stock were subject to outstanding awards under the 2014 Plan.

In March 2014, the Board and stockholders approved the 2014 Employee Stock Purchase Plan, or the ESPP, which became effective as of March 5, 2014. The Company initially reserved a total of 150,000 shares of common stock for issuance under the ESPP. Unless the Board provides otherwise, beginning on January 1, 2015, and continuing until the expiration of the ESPP, the total number of shares of common stock available for issuance under the ESPP will automatically increase annually on January 1 by the lesser of (i) 1% of the total number of issued and outstanding shares of common stock as of December 31 of the immediately preceding year, or (ii) 300,000 shares of common stock. As of June 30, 2018, the Company has issued approximately 224,000 shares of common stock under the ESPP.