10. Net loss per share attributable to common stockholders

The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2016			2015			2016			2015
	(in thousands)
Numerator:
Net loss attributable to common stockholders, basic and diluted	$	(5,709	)	$	(4,819	)	$	(22,959	)	$	(18,638	)
Denominator:
Weighted average common stock, basic and diluted	38,189			37,041			37,897			36,722
Net loss per share attributable to common stockholders:
Basic and diluted	$	(0.15	)	$	(0.13	)	$	(0.61	)	$	(0.51	)

For the three and nine months ended September 30, 2016 and 2015, we excluded all assumed exercises of stock options and the assumed issuance of common stock under RSUs from the computation of diluted net loss per share as the effect would be anti-dilutive due to the net loss for the period.

On April 1, 2013, the Company approved a stock repurchase program to repurchase up to $10,000 of the Company’s common stock in the open market, exclusive of any commissions, markups or expenses. The stock repurchased will be retired and will resume the status of authorized but unissued shares of common stock. The Company did not repurchase any of our common stock during the nine months ended September 30, 2016. As of September 30, 2016, the remaining approved amount for repurchases was approximately $5,180.