Net Loss Per Share

6 Months Ended

Jun. 30, 2015

Earnings Per Share [Abstract]

Net Loss Per Share

3. Net Loss Per Share

Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, less common stock issued that is subject to repurchase, without consideration for common stock equivalents. Diluted net loss per share is computed by dividing net loss by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. For purposes of this calculation, convertible and redeemable convertible preferred stock and warrants for preferred stock, stock options and common stock subject to repurchase are considered to be common stock equivalents and are only included in the calculation of diluted net loss per share when their effect is dilutive.

The following outstanding shares of common stock equivalents were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been antidilutive:

	As of June 30,
	2015		2014
Options to purchase common stock		3,294,849		966,778
Common stock subject to repurchase		116,674		—
Convertible preferred stock		252,817		252,818
Redeemable convertible preferred stock		17,328,059		17,236,784
Warrants for preferred stock		885,201		984,529
Total potential dilutive shares		21,877,600		19,440,909

In future periods, if the Company were to generate net income, it would allocate participating securities a proportional share of the net income, determined by dividing total weighted average participating securities by the sum of the total weighted average common shares and participating securities (the two-class method). The Company’s redeemable convertible preferred stock participate in any dividends declared by the Company and are therefore considered to be participating securities. Participating securities have the effect of diluting both basic and diluted earnings per share during periods of income.

To date, the Company has only incurred net losses and has not allocated any loss to participating securities because the preferred stockholders have no contractual obligation to share in the losses of the Company. The Company computes diluted loss per common share after giving consideration to the dilutive effect of stock options, warrants and non-vested stock that are outstanding during the period, except where such non-participating securities would be anti-dilutive.