Note 10 - Warrants

3 Months Ended

Mar. 31, 2016

Notes to Financial Statements

Warrants [Text Block]

10.  Warrants

Warrants to purchase 13,167,396 shares and 1,782,222 shares of our common stock were outstanding as of March 31, 2016 and March 31, 2015, respectively. Warrants to purchase 11,085,174 shares of common stock were issued in the 2015 Offering. Warrants to purchase 2,060,000 shares of common stock were issued in 2014 and 2015 to the guarantors of our lines of credit. The remaining warrants to purchase 22,222 shares of common stock expire on February 1, 2017 and have an exercise price of $1.50 per share. The weighted average price of the outstanding warrants to purchase an aggregate of 13,167,397 of our common stock at March 31, 2016 was $0.85.