Loss Per Share of Common Stock

6 Months Ended

Jun. 30, 2016

Loss Per Share of Common Stock

Loss Per Share of Common Stock

8. Loss Per Share of Common Stock

Basic net loss per common share is computed by dividing net loss by the weighted average number of common shares outstanding for the period.  Diluted net loss per common share is computed by giving effect to all potentially dilutive securities outstanding for the period.

In accordance with ASC Topic 260, Earnings per Share, when calculating diluted net loss per common share, the gain associated with the decrease in the fair value of certain warrants classified as derivative liabilities results in an adjustment to the net loss; and the dilutive impact of the assumed exercise of the warrants results in an adjustment to the weighted average common shares outstanding. We utilize the treasury stock method to calculate the dilutive impact of the assumed exercise of the warrants.  For the three and six months ended June 30, 2015, the effect of the adjustments for our 2006 Warrants and our 2009/2010 Warrants were dilutive.  For the three and six months ended June 30, 2016, the effect of the adjustments for our 2006 Warrants and our 2009/2010 Warrants were non-dilutive.

The following table sets forth the computation of diluted net loss per share for the three and six months ended June 30, 2015 and 2016:

	Three Months Ended June 30,				Six Months Ended June 30,
	2015		2016		2015		2016
Numerator:
Net loss	$	(11,873,047)	$	(6,746,601)	$	(24,556,029)	$	(17,811,871)
Less: income from change in fair value of warrant liability		(125,557)		—		(158,180)		—
Numerator for diluted net loss per common share	$	(11,998,604)	$	(6,746,601)	$	(24,714,209)	$	(17,811,871)
Denominator:
Basic weighted average common shares outstanding		23,332,096		24,769,083		23,074,550		24,769,083
Dilutive common shares from assumed warrant exercises		38,239		—		41,703		—
Diluted weighted average shares of common stock outstanding		23,370,335		24,769,083		23,116,253		24,769,083
Diluted net loss per share of common stock	$	(0.51)	$	(0.27)	$	(1.07)	$	(0.72)

The following potentially dilutive securities outstanding for the three and six months ended June 30, 2015 and 2016 have been excluded from the computation of diluted weighted average shares outstanding, as they would be antidilutive:

	Three Months Ended June 30,		Six Months Ended June 30,
	2015	2016	2015	2016
Warrants	23,747	54,776	23,747	54,776
Stock options	4,027,517	3,448,930	3,654,220	3,527,711
Common shares issuable upon conversion of the 8% Notes	8,058,271	8,058,271	8,058,271	8,058,271
	12,109,535	11,561,977	11,736,238	11,640,758