3. Net Income (Loss) Per Share

We compute net income (loss) per common share by dividing the net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of common stock equivalents. Diluted net income (loss) per share is computed by dividing the net income (loss) attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period. The treasury stock method is used to determine the dilutive effect of the Company’s stock option grants. Potentially dilutive securities consisting of stock issuable under options and our 2013 Employee Stock Purchase Plan (ESPP) are not included in the per common share calculation in periods where there is a net loss where the inclusion of such shares would have had an antidilutive effect.

Basic and diluted net income (loss) per common share is computed as follows (in thousands except share and per share data):


	Three Months Ended					Nine Months Ended
	September 30,					September 30,
	2018			2017		2018		2017
			(As Revised)						(As Revised)
	(in thousands, except share and per share data)
Numerator:
Net income (loss) attributable to common stockholders	$	3,150		$	(22,652)	$	(52,210)	$	(45,853)
Denominator:
Weighted-average common shares outstanding used in computing basic net income (loss)		55,974,080			46,929,498		53,165,774		46,766,562
Weighted-average common shares outstanding used in computing diluted net income (loss)		58,313,002			46,929,498		53,165,774		46,766,562
Basic net income (loss) per common share	$	0.06		$	(0.48)	$	(0.98)	$	(0.98)
Diluted net income (loss) per common share	$	0.05		$	(0.48)	$	(0.98)	$	(0.98)

For the three months ended September 30, 2018 potentially dilutive securities consisting of stock options were included in the diluted net income per common share calculation. For the three months ended September 30, 2017 and nine months ended September 30, 2018 and 2017, all outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per common share as the effect of including such securities would have been antidilutive. The table below summarizes the number of common stock equivalents included in the calculation of the weighted-average common shares outstanding used in computing diluted net income (loss):


	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2018	2017	2018	2017
	(in thousands)		(in thousands)
Options to purchase common stock	2,339	—	—	—