Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2021

The following table summarizes common stock share activity for the three and nine months ended September 30, 2021 and 2020 (dollars in thousands):

	Three Months Ended September 30, 2021
	Shares of Common Stock		Common Stock		Additional Paid-in Capital			Accumulated Deficit			Total Stockholders’ Equity
Balance, June 30, 2021		23,147,552	$	26	$	361,925		$	(329,631	)	$	32,320
Net loss		—		—		—			(605	)		(605	)
Stock-based compensation expense		—		—		588			—			588
Common stock issued through employee stock purchase		2,759		—		13			—			13
Common stock issued, net of expenses		733,937		1		5,300			—			5,301
Common stock issued for vested restricted stock units		1,322		—		(3	)		—			(3	)
Balance, September 30, 2021		23,885,570	$	27	$	367,823		$	(330,236	)	$	37,614

	Nine Months September 30, 2021
	Shares of Common Stock		Common Stock		Additional Paid-in Capital			Accumulated Deficit			Total Stockholders’ Equity
Balance, December 31, 2020		19,663,698	$	20	$	349,351		$	(326,613	)	$	22,758
Net loss		—		—		—			(3,623	)		(3,623	)
Stock-based compensation expense		—		—		1,528			—			1,528
Common stock issued through employee stock purchase		4,943		—		22			—			22
Common stock issued, net of expenses		3,250,739		6		8,707			—			8,713
Common stock issued for conversion of April 2020 Notes		959,080		1		7,452			—			7,453
Common stock issued for vested restricted stock units		7,110		—		(3	)		—			(3	)
Vested Loan Agreement warrants		—		—		766			—			766
Balance, September 30, 2021		23,885,570	$	27	$	367,823		$	(330,236	)	$	37,614

	Three Months Ended September 30, 2020
	Shares of Common Stock		Common Stock		Additional Paid-in Capital			Accumulated Deficit			Total Stockholders’ Equity
Balance, June 30, 2020		10,478,927	$	10	$	291,134		$	(284,811	)	$	6,333
Net loss		—		—		—			909			909
Stock-based compensation expense		—		—		399			—			399
Common stock issued, net of expenses		315,939		—		1,909			—			1,909
Common stock issued through employee stock purchase plan		2,284		—		9			—			9
Common stock issued for vested restricted stock units		969		—		(1	)		—			(1	)
Balance, September 30, 2020		10,798,119	$	10	$	293,450		$	(283,902	)	$	9,558

	Nine Months Ended September 30, 2020
	Shares of Common Stock		Common Stock		Additional Paid-in Capital			Accumulated Deficit			Total Stockholders’ Equity
Balance, December 31, 2019		9,741,372	$	10	$	284,313		$	(271,428	)	$	12,895
Net loss		—		—		—			(12,474	)		(12,474	)
Stock-based compensation expense		—		—		1,220			—			1,220
Common stock issued through employee stock purchase plan and stock option plans		4,652		—		28			—			28
Common stock issued, net of expenses		647,504		—		4,578			—			4,578

Common stock issued for conversion of April 2020 Notes	316,461		—		2,784			—			2,784
Common stock issued for commitment shares	70,910		—		602			—			602
Common stock issued for vested restricted stock units	17,220		—		(75	)		—			(75	)
Balance, September 30, 2020	10,798,119	$	10	$	293,450		$	(283,902	)	$	9,558

Common Stock Reserved For Future Issuances

The Company had reserved shares of common stock for future issuance as follows:

	September 30, 2021		December 31, 2020
Outstanding stock options		1,643,506		830,343
Outstanding restricted stock units		149,134		29,087
Warrants to purchase common stock associated with June 2016 Public Offering		—		421,867
Warrants to purchase common stock associated with March 2018 Public Offering – Series 2		798,810		798,810
Warrants to purchase common stock associated with December 2019 Public Offering		4,472,205		4,472,205
Warrants to purchase common stock associated with December 2020 Public Offering - Series 1		6,439,866		6,800,000
Warrants to purchase common stock associated with December 2020 Public Offering - Series 2		6,800,000		6,800,000
Prefunded warrants to purchase common stock associated with December 2020 Public Offering		3,200,000		5,260,000
Warrants to purchase common stock associated with Loan Agreement		170,410		—
Warrants to purchase common stock associated with Solar loan agreement		—		12,243
For possible future issuance for the conversion of the March 2019 Notes		1,138,200		1,138,200
For possible future issuance for the conversion of the April 2020 Notes		—		1,299,790
For possible future issuance under 2014 Plan (Note 8)		184,497		146,488
For possible future issuance under Employee Stock Purchase Plan		3,893		5,895
For possible future issuance under 2015 Plan (Note 8)		231,450		14,050
Total common shares reserved for future issuance		25,231,971		28,028,978