12. Net Income (Loss) Per Share of Common Stock

Basic net income (loss) per share is computed by dividing net income (loss) by the weighted-average number of common shares outstanding during the period. In computing diluted net income (loss) per share, net income (loss) is re-allocated to reflect the potential impact of dilutive securities, including stock options, warrants, unvested restricted stock and unvested ZSUs. Diluted net income (loss) per share is computed by dividing net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding, including potential dilutive securities. For periods in which we have generated a net loss, we do not include stock options, warrants, unvested restricted stock and unvested ZSUs in our computation of diluted net income (loss) per share, as the impact of these awards is anti-dilutive. The net per share amounts are the same for Class A, Class B and Class C common stock because the holders of each class are legally entitled to equal per share distributions whether through dividend or distribution. Further, as we assume the conversion of Class B and Class C common shares into Class A common shares for the Class A diluted net income (loss) per share computation, the net income (loss) is equal to total net income (loss) for that computation.

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


	Three Months Ended September 30,
	2013									2012
	Class			Class			Class			Class			Class			Class
	A			B			C			A			B			C
	(unaudited)
BASIC:
Net income (loss)	$	(54	)	$	(12	)	$	(2	)	$	(35,781	)	$	(15,511	)	$	(1,433	)
Weighted-average common shares outstanding		639,360			144,252			20,517			512,269			222,076			20,517

Basic net income (loss) per share	$	0.00		$	0.00		$	0.00		$	(0.07	)	$	(0.07	)	$	(0.07	)

DILUTED:
Net income (loss)	$	(54	)	$	(12	)	$	(2	)	$	(35,781	)	$	(15,511	)	$	(1,433	)
Reallocation of net income (loss) as a result of conversion of Class C shares to Class A shares		(2	)		—			—			(1,433	)		—			—
Reallocation of net income (loss) as a result of conversion of Class B shares to Class A shares		(12	)		—			—			(15,511	)		—			—

Net income (loss) attributable to common stockholders-diluted	$	(68	)	$	(12	)	$	(2	)	$	(52,725	)	$	(15,511	)	$	(1,433	)

Weighted-average common shares outstanding-basic		639,360			144,252			20,517			512,269			222,076			20,517
Conversion of Class C to Class A common shares outstanding		20,517			—			—			20,517			—			—
Conversion of Class B to Class A common shares outstanding		144,252			—			—			222,076			—			—

Weighted-average common shares outstanding-diluted		804,129			144,252			20,517			754,862			222,076			20,517

Diluted net income (loss) per share	$	0.00		$	0.00		$	0.00		$	(0.07	)	$	(0.07	)	$	(0.07	)


	Nine Months Ended September 30,
	2013									2012
	Class			Class			Class			Class			Class			Class
	A			B			C			A			B			C
	(unaudited)
BASIC:
Net income (loss)	$	(9,102	)	$	(2,333	)	$	(305	)	$	(70,840	)	$	(85,520	)	$	(4,527	)
Weighted-average common shares outstanding		613,323			157,192			20,517			321,067			387,599			20,517

Basic net income (loss) per share	$	(0.01	)	$	(0.01	)	$	(0.01	)	$	(0.22	)	$	(0.22	)	$	(0.22	)

DILUTED:
Net income (loss) attributable to common stockholders-basic	$	(9,102	)	$	(2,333	)	$	(305	)	$	(70,840	)	$	(85,520	)	$	(4,527	)
Reallocation of net income (loss) as a result of conversion of Class C shares to Class A shares		(305	)		—			—			(4,527	)		—			—
Reallocation of net income (loss) as a result of conversion of Class B shares to Class A shares		(2,333	)		—			—			(85,520	)		—			—

Net income (loss) attributable to common stockholders-diluted	$	(11,740	)	$	(2,333	)	$	(305	)	$	(160,887	)	$	(85,520	)	$	(4,527	)

Weighted-average common shares outstanding-basic		613,323			157,192			20,517			321,067			387,599			20,517
Conversion of Class C to Class A common shares outstanding		20,517			—			—			20,517			—			—
Conversion of Class B to Class A common shares outstanding		157,192			—			—			387,599			—			—

Weighted -average common shares outstanding-diluted		791,032			157,192			20,517			729,183			387,599			20,517

Diluted net income (loss) per share	$	(0.01	)	$	(0.01	)	$	(0.01	)	$	(0.22	)	$	(0.22	)	$	(0.22	)

The following weighted-average equity awards were excluded from the calculation of diluted net income (loss) per share because their effect would have been anti-dilutive for the periods presented (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2013		2012		2013		2012
Stock options		60,320		80,385		65,803		88,720
Warrants		695		695		695		695
Restricted shares		3,649		13,915		4,439		16,394
ZSUs		63,448		73,855		61,326		74,750

Total		128,112		168,850		132,263		180,559