Net Income (Loss) Per Share Attributable to Common Stockholders and Pro Forma Net Loss Per Share

6 Months Ended

Jun. 30, 2012

Net Income (Loss) Per Share Attributable to Common Stockholders and Pro Forma Net Loss Per Share [Abstract]

Net Income (Loss) Per Share Attributable to Common Stockholders and Pro Forma Net Loss Per Share

(6) Net Income (Loss) Per Share Attributable to Common Stockholders and Pro Forma Net Loss Per Share

The following tables present the calculation of basic and diluted net income (loss) per share attributable to common stockholders (in thousands, except share and per share data):

	Three Months Ended June 30,						Six Months Ended June 30,
	2012			2011			2012			2011
Numerator:
Net income (loss)	$	(8,724	)	$	2,036		$	(14,364	)	$	5,027
Accretion of redeemable convertible preferred stock		(154	)		(158	)		(308	)		(314	)
Net income attributable to participating securities		—			(1,520	)		—			(3,835	)
Net income (loss) attributable to common stockholders - Basic	$	(8,878	)	$	358		$	(14,672	)	$	878
Undistributed earnings reallocated to participating securities	$	—		$	133		$	—		$	331
Net income (loss) attributable to common stockholders - Diluted	$	(8,878	)	$	491		$	(14,672	)	$	1,209
Denominator:
Weighted-average shares outstanding - Basic		27,788,547			19,668,851			26,452,100			19,188,210
Effect of potentially dilutive securities:
Common stock options		—			9,915,374			—			9,745,364
Weighted-average shares outstanding - Diluted		27,788,547			29,584,225			26,452,100			28,933,574
Net income (loss) per share attributable to common stockholders:
Basic	$	(0.32	)	$	0.02		$	(0.55	)	$	0.05
Diluted	$	(0.32	)	$	0.02		$	(0.55	)	$	0.04

Potentially dilutive securities not included in the calculation of diluted net income (loss) per share because doing so would be antidilutive are as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2012		2011		2012		2011
Common stock options		38,134,900		7,390,998		38,134,900		5,527,537
Convertible preferred stock		83,703,016		83,703,016		83,703,016		83,703,016
Restricted stock units		1,032,304		—		1,032,304		—
Common stock subject to repurchase		473,103		302,842		473,103		168,487
ESPP obligations (1)		701,671		—		701,671		—
Total potentially dilutive securities		124,044,994		91,396,856		124,044,994		89,399,040

⁽¹⁾  ESPP obligations for the three and six months ended June 30, 2012 represents an estimate, which includes the maximum employee contribution of 15% of each employee’s total compensation.