Net Income (Loss) per Share

Net income (loss) per share is presented in conformity with the two‑class method required for multiple classes of common stock and participating securities.

The participating securities include Series C, D, E, F and G convertible preferred stock, as the holders of these series of preferred stock are entitled to receive a noncumulative dividend in preference to the common stockholders in the event that a dividend is declared on common stock. During the three months ended March 31, 2018 the amount of income generated by the Company was less than the stated annual dividend amount that would have been allocated to the preferred stockholders in the event that a dividend had been declared and thus no income has been allocated to the common stockholders. The holders of Series C, D, E, F and G preferred stock do not have a contractual obligation to share in the losses. As such, net loss for the three months ended March 31, 2017 was not allocated to these participating securities.

Basic income (loss) per share is computed using the weighted average number of common shares outstanding during the period, and excludes any dilutive effects of common stock equivalent shares such as stock options, warrants, and convertible preferred stock. Diluted income (loss) per share is computed using the weighted average number of common shares outstanding and potentially dilutive common stock options, warrants, and convertible preferred stock.

The following table sets forth the calculation of basic and diluted net income (loss) per share attributable to common stockholders during the periods presented:



	Three Months Ended March 31,
(in thousands, except per share data)	2018			2017
Numerator:
Net income (loss)	$	2,916		$	(1,213	)
Participating securities:
Income allocated to participating securities	(2,916		)	—
Net income (loss) attributable to common stockholders	—			(1,213		)

Denominator:
Weighted-average common shares outstanding, basic and diluted	3,031			2,600
Net income (loss) per share:
Net income (loss) per share attributable to common stockholders, basic and diluted	$	0.00		$	(0.47	)

The following potentially dilutive shares of convertible preferred stock, preferred stock warrants, and stock options were not included in the calculation of diluted shares above as the effect would have been anti‑dilutive:



	Three Months Ended March 31,
(in thousands)	2018	2017
Convertible preferred stock	24,642	19,837
Preferred stock warrants	214	214
Stock options to purchase common stock	5,630	4,382
Total	30,486	24,433