Net Loss per Share

3 Months Ended

Mar. 31, 2013

Earnings Per Share [Abstract]

Net Loss per Share

7. Net Loss per Share

A reconciliation of the number of shares used in the calculation of basic and diluted net loss per share is as follows (in thousands):

	Three Months Ended March 31,
	2013		2012
Weighted-average shares of common stock outstanding		28,024		15,901
Less: weighted-average number of unvested restricted common shares outstanding		—		58
Weighted-average number of common shares used in calculating net loss per common share		28,024		15,843

The following potentially dilutive common stock equivalent shares have been excluded from the computation of the weighted-average shares outstanding as their effect would have been anti-dilutive (in thousands):

	Three Months Ended March 31,
	2013		2012
Redeemable convertible preferred stock		—		8,696
Options outstanding		3,401		3,971
Restricted stock units outstanding		1,419		—
Unvested restricted shares		—		58
Warrants		28		47
Total		4,848		12,772