Quarterly report pursuant to Section 13 or 15(d)

Warrants

Warrants

6 Months Ended

Jun. 30, 2015

The following is a summary of activity in the number of warrants outstanding to purchase the Company’s common stock for the six months ended June 30, 2015 (in thousands):

	Warrants accounted for as: Equity							Warrants accounted for as: Liabilities
	January 2012 warrants		March 2013 warrants		April 2013 warrants			February 2012 warrants		August 2013 warrants			October 2013 warrants			October 2013 Series A warrants			January 2014 warrants			Total

Outstanding, December 31, 2014		650		455		1,864			1,000		10,000			200			7,100			5,500			26,769
Warrants exercised		-		-		(864	)		-		(10,000	)		(200	)		(6,325	)		(1,000	)		(18,389	)
Outstanding, June 30, 2015		650		455		1,000			1,000		-			-			775			4,500			8,380
Expiration date	January 11, 2016		March 1, 2016		April 25, 2018			February 28, 2016		August 26, 2023			October 18, 2018			October 24, 2023			January 16, 2024

For the six months ended June 30, 2015, there were a total of 18,389,000 warrants exercised. All warrants were exercised on a net exercise basis and resulted in the issuance of 8,636,000 shares of the Company’s common stock during that period.

Warrants consist of warrants potentially settleable in cash, which are liability-classified warrants, and equity-classified warrants.

Warrants classified as liabilities

Liability-classified warrants consist of warrants issued in connection with equity financings in February 2012, October 2013 and January 2014. These warrants are potentially settleable in cash and were determined not to be indexed to the Company’s own stock and are therefore accounted for as liabilities.

The estimated fair value of outstanding warrants accounted for as liabilities is determined at each balance sheet date. Any decrease or increase in the estimated fair value of the warrant liability since the most recent balance sheet date is recorded in the consolidated statement of comprehensive loss as changes in fair value of derivative liabilities. The fair value of the warrants classified as liabilities is estimated using the Black-Scholes option-pricing model with the following inputs as of June 30, 2015:

	February 2012 warrants			October 2013 warrants			January 2014 warrants

Strike price	$	0.60		$	0.50		$	0.50

Expected term (years)		0.7			8.3			8.6
Cumulative volatility %		82	%		100	%		103	%
Risk-free rate %		0.27	%		2.17	%		2.19	%

The Company’s expected volatility is based on a combination of implied volatilities of similar publicly traded entities given that the Company has limited history of its own observable stock price. The expected life assumption is based on the remaining contractual terms of the warrants. The risk-free rate is based on the zero coupon rates in effect at the balance sheet date. The dividend yield used in the pricing model is zero, because the Company has no present intention to pay cash dividends.

Warrants classified as equity

Warrants that were recorded in equity at fair value upon issuance, and are not reported as liabilities on the balance sheet, are included in the above table which shows all warrants.