Net Loss per Share

9 Months Ended

Sep. 30, 2017

11. Net Loss per Share

Basic net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period, excluding shares subject to repurchase and without consideration of potentially dilutive securities. Diluted net loss per share is computed by giving effect to all potentially dilutive common shares outstanding for the period. For purposes of this computation, outstanding common stock options, restricted stock units, unvested common shares subject to repurchase and warrants are considered to be common share equivalents. Common share equivalents are excluded from the computation in periods in which they have an anti-dilutive effect.

For the three and nine months ended September 30, 2017, the warrants were excluded from the computation of diluted net loss per share as the change in its fair value and assumed exercises yielded an anti-dilutive effect. Other potentially dilutive common share equivalents such as outstanding common stock options, restricted stock and unvested common shares subject to repurchase were not included in the computation of diluted net loss per share for all periods as they also gave an anti-dilutive effect, which represents a reduction of the net loss per share.

The following table provides the basic and diluted net loss per share computations for the three and nine months ended September 30, 2017 and 2016.


	Three months ended				Nine months ended
	September 30,				September 30,
(in thousands, except per share data)	2017		2016		2017		2016

Numerator:
Net loss, basic and diluted	$	(27,119)	$	(26,017)	$	(90,812)	$	(57,858)

Denominator:
Weighted-average shares outstanding		53,447		52,012		53,100		51,422
Less: weighted-average unvested shares subject to repurchase		—		—		—		(121)
Weighted-average number of shares used in computing net loss per share, basic and diluted		53,447		52,012		53,100		51,301

Net loss per share, basic and diluted	$	(0.51)	$	(0.50)	$	(1.71)	$	(1.13)

The following table shows total outstanding potentially dilutive shares excluded from the computation of diluted loss per share as their effect would be anti-dilutive, as of September 30, 2017 and 2016:


	September 30,
	2017	2016
	(in thousands)
Options to purchase common stock	9,959	9,146
Warrants to purchase common stock	377	377
Restricted stock units	379	174
Employee stock purchase plan	201	145
	10,916	9,842