13. Net Loss per Share

Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2018		2019		2018
Numerator:
Net Loss	$	(47,015)	$	(26,362)	$	(118,986)	$	(62,012)

Denominator:
Weighted average common shares outstanding, basic and diluted		79,115,305		62,311,111		78,357,791		26,662,233
Net loss per share, basic and diluted	$	(0.59)	$	(0.42)	$	(1.52)	$	(2.33)

The Company’s potential dilutive securities have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential common shares from the periods in the table above, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect:


	September 30,
	2019	2018
Restricted common stock	397,252	2,644,423
Stock options to purchase common stock	15,849,584	14,701,283
	16,246,836	17,345,706