Net Loss Per Share Attributable to Common Stockholders

12 Months Ended

Dec. 31, 2016

Net Loss Per Share Attributable to Common Stockholders

Note 8. Net Loss Per Share Attributable to Common Stockholders

The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for companies with participating securities. The Company considers all series of convertible preferred stock to be participating securities. Under the two-class method, the net loss attributable to common stockholders is not allocated to the convertible preferred stock as the holders of convertible preferred stock do not have a contractual obligation to share in losses.

The diluted net loss per share attributable to common stockholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, convertible preferred stock, options to purchase common stock and warrants to purchase common stock and convertible preferred stock are considered common stock equivalents, but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is antidilutive. Basic and diluted net loss per share was the same for each period presented, as the inclusion of all potential common shares outstanding would have been antidilutive.

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


	Years Ended December 31,
	2016			2015			2014
Numerator:
Net loss attributable to common stockholders	$	(31,553	)	$	(41,007	)	$	(32,872	)
Denominator:
Weighted-average common shares outstanding - basic and diluted		19,595			12,653			12,080
Net loss per common share - basic and diluted	$	(1.61	)	$	(3.24	)	$	(2.72	)

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


	Years Ended December 31,
	2016		2015		2014
Options to purchase common shares		10,969		9,294		8,283
Restricted stock units		41		—		—
Employee stock purchase plan shares		29		—		—
Common stock warrant		36		6		—
Convertible preferred shares (as converted)		13,505		18,240		18,240
Preferred stock warrant (as converted)		20		27		27
		24,600		27,567		26,550