At June 30, 2015, there were warrants outstanding to purchase 8,896,848 shares of common stock with a weighted average exercise price of $0.99 and a weighted average remaining life of four years. During the six months ended June 30, 2015, warrants to purchase 4,598,129 shares of common stock were exercised for net proceeds (see Note 8) of approximately $4,398,000. Additionally, in accordance with the warrant agreements, warrants to purchase 215,000 shares of common stock were exercised in cashless exercises resulting the issuance of 176,145 shares. There were no warrants issued or cancelled during the six months ended June 30, 2015.