12. Net Loss Per Share

The following table presents the calculation of basic and diluted net loss per share of common stock for the periods indicated:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2019		2018		2019		2018
	(unaudited)					(unaudited)
Net loss attributable to common shareholders (basic and diluted)	$	(11,682,949)	$	(6,138,352)	$	(36,707,937)	$	(20,487,172)
Shares used to compute net loss per common share, basic and diluted		5,841,790		162,506		2,746,523		143,012
Net loss per share attributable to common shareholders, basic and diluted	$	(2.00)	$	(37.77)	$	(13.37)	$	(143.25)

Basic net loss per share is calculated by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted-average number of common shares and common share equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company's potentially dilutive securities which include stock options, convertible preferred stock and common stock warrants have been excluded from the computation of diluted net loss per share as they would be anti-dilutive. For all periods presented, there is no difference in the number of shares used to compute basic and diluted shares outstanding due to the Company's net loss position.

The following outstanding common stock equivalents have been excluded from diluted net loss per common share for the nine months ended September 30, 2019 and 2018 because their inclusion would be anti-dilutive.


	September 30,	September 30,
	2019	2018
	(unaudited)
Options issued and outstanding	3,821,690	42,979
Inducement options issued and outstanding	—	2,994
Options available for grant under stock options plans	554,016	3,402
Restricted stock unit awards issued and outstanding	5,613	5,613
Warrants issued and outstanding	19,421,892	16,582
Convertible notes	—	23,469
Series A convertible preferred stock	473,565	—
Series B convertible preferred stock	985,500	—
Total	25,262,276	95,039