Net Income (Loss) Per Share Attributable to Common Stockholders

The following table presents the basic and diluted net income (loss) per share attributable to common stockholders:



	Year Ended
	December 31, 2015			December 31, 2014			December 31, 2013

	(In thousands, except per share data)
Basic EPS:
Net income (loss) attributable to common stockholders	$	422		$	(19,789	)	$	(13,493	)
Weighted-average common shares outstanding	42,067			29,921			11,540
Weighted-average unvested restricted shares	(1,677		)	(1,704		)	(52		)
Weighted-average escrow shares	(727		)	—			—
Weighted-average common shares outstanding used to compute net income (loss) per share attributable to common stockholders	39,663			28,217			11,488
Basic net income (loss) per share attributable to common stockholders	$	0.01		$	(0.70	)	$	(1.17	)
Diluted EPS:
Net income (loss) attributable to common stockholders	$	422		$	(19,789	)	$	(13,493	)
Weighted-average common shares used in basic EPS	39,663			28,217			11,488
Dilutive effect of weighted-average common stock options	2,510			—			—
Dilutive effect of weighted-average restricted stock awards	532			—			—
Dilutive effect of weighted-average restricted stock units	426			—			—
Dilutive effect of weighted-average ESPP	25			—			—
Dilutive effect of weighted-average escrow shares	591			—			—
Dilutive effect of weighted-average contingent shares	748			—			—
Weighted-average shares used to compute diluted net income (loss) per share attributable to common stockholders	44,495			28,217			11,488
Diluted net income (loss) per share attributable to common stockholders	$	0.01		$	(0.70	)	$	(1.17	)

The following shares have been excluded from the calculation of diluted net loss per share attributable to common stockholders for each period presented because they are anti-dilutive:



	December 31, 2015	December 31, 2014	December 31, 2013

	(in thousands)
Options to purchase common stock	—	8,113	8,360
Unvested restricted stock awards	—	1,750	—
Unvested restricted stock units	—	845	—
Shares held in escrow	—	125	—
Contingent shares	704	—	—
Conversion of convertible preferred stock	—	—	14,410
Conversion of preferred stock warrants	—	—	436
Total shares excluded from net income (loss) per share attributable to common stockholders	704	10,833	23,206

Prior to December 31, 2015, shares contingently issuable if certain milestones were achieved on December 31, 2015 related to business combinations that occurred during the year ended December 31, 2014 were excluded from the calculation of diluted net income (loss) per share attributable to common stockholders for the year ended December 31, 2014.

In connection with the acquisition of Chango, which occurred during the year ended December 31, 2015, the Company agreed to pay up to $18.2 million of contingent consideration in addition to 126,098 shares held in escrow, if certain milestones were achieved by December 31, 2015. The Company had the option to pay the contingent consideration in cash or common stock, or a combination thereof. As of December 31, 2015, the entire contingent consideration issuable in connection with the Chango acquisition was deemed earned (See Note 7). The Company elected to pay the contingent consideration in shares, with the number of shares issued in connection with the contingent consideration based on the greater of the volume-weighted-average closing prices of the Company's common stock for the ten consecutive trading days ending on (and including) the trading day that is one day prior to December 31, 2015 and $18.77. On December 31, 2015, the Company issued 971,481 shares in connection with the contingent consideration and released 126,098 shares from escrow. These shares were included in the calculation of basic net income (loss) per share attributable to common stockholders effective December 31, 2015, the date of issuance, and were included in the calculation of diluted net income (loss) per share attributable to common stockholders for periods between the date of acquisition and immediately prior to December 31, 2015.

In connection with the acquisition of iSocket, Inc., or iSocket, which occurred during the year ended December 31, 2014, the Company was required to issue up to $9.6 million of contingent consideration payable in shares of common stock if certain performance milestones were achieved by December 31, 2015. The number of shares issued was based on the average closing price of the Company's common stock for the ten consecutive trading days ending on (and including) the last trading day of 2015. On December 31, 2015, the Company issued 585,170 shares in connection with the contingent consideration. These shares were included in the calculation of basic net income (loss) per share attributable to common stockholders effective December 31, 2015, the date of issuance, and were excluded in the calculation of diluted net income (loss) per share attributable to common stockholders for periods between the date of acquisition and immediately prior to December 31, 2015 because they were anti-dilutive.

For the years ended December 31, 2014 and 2013, the Company increased net loss by $1.1 million and $4.2 million, respectively, for cumulative preferred stock dividends in determining its net loss attributable to common stockholders. Upon the completion of the Company’s IPO in April 2014, all of the preferred stock converted to common stock and accordingly, after the IPO the Company was no longer required to increase its net loss for preferred stock dividends in determining its net loss attributable to common stockholders.