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

Basic 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 during the period. In computing diluted net income (loss) attributable to common stockholders, 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 or there is no income attributable to common stockholders, 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 (on a one-to-one basis) 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 June 30,
	2017						2016
	Class		Class		Class		Class			Class			Class
	A		B		C		A			B			C
	(unaudited)
BASIC:
Net income (loss) attributable to common stockholders	$	4,565	$	407	$	121	$	(3,805	)	$	(537	)	$	(104	)
Weighted-average common shares outstanding		773,704		68,904		20,517		747,482			105,394			20,517
Basic net income (loss) per share	$	0.01	$	0.01	$	0.01	$	(0.01	)	$	(0.01	)	$	(0.01	)
DILUTED:
Net income (loss) attributable to common stockholders	$	4,565	$	407	$	121	$	(3,805	)	$	(537	)	$	(104	)
Reallocation of net income (loss) as a result of conversion of Class C shares to Class A shares		121		—		—		(104	)		—			—
Reallocation of net income (loss) as a result of conversion of Class B shares to Class A shares		407		—		—		(537	)		—			—
Net income (loss) attributable to common stockholders-diluted	$	5,093	$	407	$	121	$	(4,446	)	$	(537	)	$	(104	)
Weighted-average common shares outstanding-basic		773,704		68,904		20,517		747,482			105,394			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		68,904		—		—		105,394			—			—
Weighted-average effect of dilutive securities:
Stock options and employee stock purchase plan		9,811		917		—		—			—			—
ZSUs		14,710		—		—		—			—			—
Performance-based ZSUs		345		—		—		—			—			—
Weighted-average common shares outstanding-diluted		887,991		69,821		20,517		873,393			105,394			20,517
Diluted net income (loss) per share	$	0.01	$	0.01	$	0.01	$	(0.01	)	$	(0.01	)	$	(0.01	)

	Six Months Ended June 30,
	2017									2016
	Class			Class			Class			Class			Class			Class
	A			B			C			A			B			C
	(unaudited)
BASIC:
Net income (loss) attributable to common stockholders	$	(3,896	)	$	(382	)	$	(103	)	$	(26,384	)	$	(3,891	)	$	(729	)
Weighted-average common shares outstanding		772,679			75,829			20,517			742,271			109,455			20,517
Basic net income (loss) per share	$	(0.01	)	$	(0.01	)	$	(0.01	)	$	(0.04	)	$	(0.04	)	$	(0.04	)
DILUTED:
Net income (loss) attributable to common stockholders	$	(3,896	)	$	(382	)	$	(103	)	$	(26,384	)	$	(3,891	)	$	(729	)
Reallocation of net income (loss) as a result of conversion of Class C shares to Class A shares		(103	)		—			—			(729	)		—			—
Reallocation of net income (loss) as a result of conversion of Class B shares to Class A shares		(382	)		—			—			(3,891	)		—			—
Net income (loss) attributable to common stockholders-diluted	$	(4,381	)	$	(382	)	$	(103	)	$	(31,004	)	$	(3,891	)	$	(729	)
Weighted-average common shares outstanding-basic		772,679			75,829			20,517			742,271			109,455			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		75,829			—			—			109,455			—			—
Weighted-average common shares outstanding-diluted		869,025			75,829			20,517			872,243			109,455			20,517
Diluted net income (loss) per share	$	(0.01	)	$	(0.01	)	$	(0.01	)	$	(0.04	)	$	(0.04	)	$	(0.04	)

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

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Stock options and employee stock purchase plan		16,827		24,939		35,138		24,059
Restricted shares		—		3,692		1,062		4,580
ZSUs		2,770		63,239		49,263		62,983
Total		19,597		91,870		85,463		91,622