13. Stock Warrants

The following is a description of the common stock warrant activity of the Company:


(in thousands, except per share amounts)	Warrants for the Purchase of Common Stock			Weighted Average Exercise Price
Balance—December 31, 2012		2,842		$	3.05
Exercised		(65	)	$	2.82

Balance—December 31, 2013		2,777		$	3.05
Exercised		(396	)	$	3.38

Balance—December 31, 2014		2,381		$	3.00
Exercised		(2,355	)	$	3.00
Cancelled		(26	)	$	3.00

Balance—December 31, 2015		—		$	—

During the year ended December 31, 2013, warrants to purchase approximately 65,000 shares of common stock were cashless exercised and 35,000 shares of common stock were issued. During the year ended December 31, 2014, warrants to purchase approximately 75,000 shares of common stock were cashless exercised and 38,000 shares of common stock were issued. During the year ended December 31, 2015, warrants to purchase approximately 2,295,000 shares of common stock were cashless exercised and 1,695,000 shares of common stock were issued. As of December 31, 2015, all remaining unexercised warrants for the purchase of common stock had expired and were cancelled.