Capital Stock

Exercise of Options

For the nine months ended September 30, 2017 and 2016, 63,509 and 361,145 shares, respectively, were exercised at a weighted-average exercise price of $2.76 and $2.60 per share, respectively, with net cash proceeds of $0.2 million and $0.9 million, respectively.

Warrants

On September 28, 2017, warrants to purchase 72,727 shares of common stock, at an exercise price of $8.25 per share, expired. No warrants were outstanding as of September 30, 2017.

Public Offering

In April 2017, we completed a public offering in which we issued and sold 6.3 million shares of our common stock, par value $0.0001 per share, at a public offering price of $4.00 per share. We received net proceeds of approximately $23.2 million after deducting the underwriting discounts, commissions and other offering expenses of $0.6 million.

Consolidated statements of stockholders' equity as of September 30, 2017 and 2016 are as follows (in thousands):



								Accumulated
					Additional			Other						Total
	Common Stock				Paid-in			Comprehensive			Accumulated			Stockholders’
	Shares		Amount		Capital			Income			Deficit			Equity
December 31, 2015	40,343		$	4	$	305,981		$	405		$	(283,511	)	$	22,879
Exercise of stock options	361		—		939			—			—			939
Release of stock awards	911		—		—			—			—			—
Employee stock-based compensation	—		—		3,861			—			—			3,861
Cancelled shares	(397	)	—		(1,523		)	—			—			(1,523		)
Total comprehensive loss	—		—		—			(22		)	(3,298		)	(3,320		)
September 30, 2016	41,218		$	4	$	309,258		$	383		$	(286,809	)	$	22,836

December 31, 2016	41,255		$	4	$	311,164		$	—		$	(292,069	)	$	19,099
Exercise of stock options	64		—		175			—			—			175
Release of stock awards	1,096		—		—			—			—			—
Employee stock-based compensation	—		—		5,212			—			—			5,212
Cancelled shares	(397	)	—		(1,670		)	—			—			(1,670		)
Issuance of common stock, net of issuance costs	6,325		1		23,229			—			—			23,230
Total comprehensive loss	—		—		—			13			(23,966		)	(23,953		)
September 30, 2017	48,343		$	5	$	338,110		$	13		$	(316,036	)	$	22,092