Net Income (Loss) per Share Attributable to Common Stockholders

6 Months Ended

12 Months Ended

Jun. 30, 2013

Dec. 31, 2012

Net Income (Loss) per Share Attributable to Common Stockholders

10. Net Income (Loss) per Share Attributable to Common Stockholders

The following outstanding shares of common stock equivalents were excluded from the computation of diluted net income (loss) per share attributable to common stockholders for the periods presented because including them would have been antidilutive:

	Six Months Ended June 30,
	2012		2013
Convertible preferred stock		24,026,797		—
Common stock subject to repurchase		—		875
Stock options to purchase common stock		1,540,613		3,787,915
Preferred stock warrants		81,075		—
Common stock warrants		1,500		82,575

The following table sets forth the computation of our unaudited basic and diluted net income (loss) per share attributable to common stockholders (in thousands, except share and per share data):

	Six Months Ended June  30,
	2013			2012
Net income (loss)	$	(39,741	)	$	36,636
Noncumulative dividends on convertible preferred stock )		—			(12,664	)
Undistributed earnings allocated to participating securities )		—			(22,715	)
Net income (loss) attributable to common stockholders, basic		(39,741	)		1,257
Adjustment to undistributed earnings allocated to participating securities		—			559
Net income (loss) attributable to common stockholders, diluted	$	(39,741	)	$	1,816
Basic shares:
Weighted average common shares outstanding		8,078,308			1,329,133
Diluted shares:
Weighted average common shares outstanding		8,078,308			1,329,133
Weighted average effect of dilutive stock options		—			639,688
		8,078,308			1,968,821
Net income (loss) per share attributable to common stockholders:
Basic	$	(4.92	)	$	0.95
Diluted	$	(4.92	)	$	0.92

15. Net Income (Loss) per Share Attributable to Common Stockholders

The following table sets forth the computation of our basic and diluted net income (loss) per share attributable to common stockholders (in thousands, except share and per share data):

	Year Ended December 31,
	2010			2011			2012
Net income (loss)	$	(20,269	)	$	19,984		$	11,366
Noncumulative dividends on convertible preferred stock		–			(18,757	)		(11,366	)
Undistributed earnings allocated to participating securities		–			(1,148	)		–
Net income (loss) attributable to common stockholders, basic		(20,269	)		79			–
Adjustment to undistributed earnings allocated to participating securities		–			48			–
Net income (loss) attributable to common stockholders, diluted	$	(20,269	)	$	127		$	–
Shares used in computing net income (loss) per share attributable to common stockholders, basic		1,207,106			1,249,778			1,350,939
Dilutive effect of common stock options		–			839,428			697,928
Shares used in computing net income (loss) per share attributable to common stockholders, diluted		1,207,106			2,089,206			2,048,867
Net income (loss) per share attributable to common stockholders:
Basic	$	(16.79	)	$	0.06		$	0.00
Diluted	$	(16.79	)	$	0.06		$	0.00

The following outstanding shares of common stock equivalents were excluded from the computation of diluted net income (loss) per share attributable to common stockholders for the periods presented because including them would have been antidilutive:

	Year Ended December 31,
	2010		2011		2012
Convertible preferred stock		17,103,729		24,026,797		24,026,797
Common stock subject to repurchase		13,662		–		–
Stock options to purchase common stock		290,166		962,225		1,653,298
Convertible preferred stock warrants		81,075		81,075		81,075
Common stock warrants		1,500		1,500		1,500