At June 30, 2016, there were warrants outstanding to purchase 1,964,250 shares of common stock with a weighted average exercise price of $0.97 and a weighted average remaining life of 2.83 years. During the six months ended June 30, 2016, warrants to purchase 3,750 shares of common stock were exercised on a cashless basis resulting in the issuance of 1,849 shares and 1,250 shares of common stock were exercised on a for cash basis. During the six months ended June 30, 2015, warrants to purchase 4,598,129 shares of common stock were exercised for net proceeds of approximately $4,398,000. There were no warrants issued or cancelled during the six months ended June 30, 2016 and 2015.