Note 9 - Stockholders' equity

On July 7, 2010, the Company sold 2,737,500 units, with the aggregate units consisting of 2,737,500 shares of the Company’s common stock and warrants to purchase 1,368,750 shares, at a price of $2.00 per unit in a registered direct offering (the “2010 Offering”). The warrants issued as part of the 2010 Offering had an exercise price of $2.60 per share and were exercisable for a five-year period, which commenced on January 7, 2011. The net proceeds pursuant to the 2010 Offering were approximately $4.9 million. The value of the aggregate number of warrants issued pursuant to the 2010 Offering was approximately $1.3 million and such amount was charged as a component of stockholders’ equity to additional paid-in capital.

Effective as of March 4, 2011, the Company re-purchased warrants to purchase 150,000 shares of the Company’s common stock, at a price of $0.60 per share, which warrants were issued in connection with the 2010 Offering.

On March 7, 2011, the remaining 1,218,750 warrants issued in connection with the 2010 Offering were amended upon consent of the holders of more than two-thirds of the remaining warrants, to among other things, extend the expiration date of the warrants to July 7, 2016.

Between January 2016 and July 2016, 1,161,252 warrants issued in connection with the 2010 Offering were exercised at $2.60 per share. In July 2016, 7,498 warrants issued in connection with the 2010 Offering expired.

On December 8, 2016 the Company entered into an Underwriting Agreement with two investment banking firms for themselves and as representatives for two other investment banking firms (collectively, the “Underwriters”), in connection with an underwritten offering (the “Offering”) of 6,428,571 shares of the Company’s common stock, par value $0.01 per share (the “Firm Shares”). Pursuant to the Underwriting Agreement, the Company agreed to sell to the Underwriters, and the Underwriters agreed to purchase from the Company, an aggregate of 6,428,571 shares of common stock and also granted the Underwriters a 30 day option to purchase up to 964,285 additional shares of its common stock to cover over-allotments, if any. The Company also agreed to reimburse certain expenses incurred by the Underwriters in the Offering.

The closing of the Offering was held on December 14, 2016, at which time the Company sold 7,392,856 shares of its common stock to the Underwriters (including 964,285 shares to cover over-allotments) at a price to the public of $7.00 per share, less underwriting discounts and commissions, and received gross proceeds of $51.7 million. The Company incurred approximately $3.3 million of transaction fees in connection with the Offering, resulting in net proceeds of $48.4 million.