STOCKHOLDERS' EQUITY

6 Months Ended

Jun. 30, 2013

Stockholders' Equity Attributable to Parent [Abstract]

Stockholders' Equity Note Disclosure

STOCKHOLDERS’ EQUITY

Common Stock.

Our Board of Directors is authorized to issue up to 150,000,000 shares of common stock, from time to time, as provided in a resolution or resolutions adopted by our shareholders.

On February 7, 2012, we entered into definitive agreements with institutional and other accredited investors and raised approximately $22.0 million in a private placement financing (the "Private Placement"), which included an aggregate of $3.0 million in convertible notes issued in December 2011 to entities affiliated with Third Security, LLC, a related party, that automatically converted into shares of our common stock and warrants to purchase such common stock on the same terms as all investors in the Private Placement. Pursuant to the purchase agreement, we issued an aggregate of 19,000,000 shares of our common stock at a price per share of $1.00, as well as five-year warrants to purchase up to an aggregate of 11,435,158 shares of common stock with an exercise price of $1.08 per share. In connection with the conversion of the convertible notes issued by us to the entities associated with Third Security, LLC, the entities received an aggregate of 3,000,000 shares of common stock and 1,736,110 warrants on the same terms as all investors in the Private Placement. The costs incurred to complete the Private Placement were recorded as a reduction in equity in the amount of $1.5 million. Net proceeds from this offering are being used for general corporate and working capital purposes, primarily to accelerate development of several of our key initiatives.

On January 24, 2013, we entered into a Securities Purchase Agreement with certain institutional and other accredited investors pursuant to which we: (i) sold to the investors an aggregate of 16,600,000 shares of our common stock at a price per share of $0.50 for aggregate gross proceeds of approximately $8.3 million; and (ii) issued to the investors warrants to purchase up to an aggregate of 8,300,000 shares of common stock with an exercise price of $0.75 per share (the "Offering"). The warrants may be exercised, in whole or in part, at any time from January 30, 2013 until January 30, 2018 and contain both cash and “cashless exercise” features. Affiliates of Third Security, LLC, a related party, purchased an aggregate of 6,000,000 shares of common stock and warrants to purchase an aggregate of 3,000,000 shares of common stock in the Offering on the same terms as the other investors. We are using the net proceeds from the Offering for general corporate and working capital purposes, primarily to accelerate development of several of our key initiatives.

In connection with the Offering, we entered into a registration rights agreement with the investors (the “Registration Rights Agreement”). The Registration Rights Agreement required that we file with the Securities and Exchange Commission a registration statement to register for resale the shares and the shares of common stock issuable upon exercise of the warrants (the “Warrant Shares”) by March 16, 2013. The registration statement was filed with the Securities and Exchange Commission on March 15, 2013 and was declared effective by the Securities and Exchange Commission on March 29, 2013.

Common Stock Warrants.

During the six months ended June 30, 2013 and 2012, we issued warrants to purchase 8,300,000 and 13,171,268, shares of common stock, respectively, and none of the issued warrants were exercised. Included in the warrants issued in 2013 were 8,300,000 warrants issued in connection with the sales of common stock on January 24, 2013. Included in the warrants issued in 2012 were 1,791,268 warrants issued due to repricing requirements contained in the February 2012 warrant agreement. Warrants to purchase an aggregate of 26,643,676 shares of common stock were outstanding at June 30, 2013.

Warrant Holder	Issue Year	Expiration	Underlying Shares	Exercise Price
Affiliates of Third Security, LLC(1)	2010	December 2015	5,172,408	$0.58
Various Institutional Holders(2)	2012	February 2017	11,435,158	$1.08
Affiliates of Third Security, LLC(2)	2012	February 2017	1,736,110	$1.08
Various Institutional Holders(3)	2013	January 2018	5,300,000	$0.75
Affiliates of Third Security, LLC(3)	2013	January 2018	3,000,000	$0.75
			26,643,676

(1) This warrant was issued in connection with the issuance of warrants to purchase shares of our Series A Preferred Stock to affiliates of Third Security, LLC in December 2010. The number of underlying shares shown reflects the number of shares of common stock issuable upon conversion of the shares of Series A Preferred Stock for which this warrant is currently exercisable.

(2) These Warrants were issued in connection with the private placement completed in February 2012. Warrants were repriced and additional warrants were issued in connection with the warrants issued with the private placement completed in January 2013.

(3) These warrants were issued in connection with the private placement completed in January 2013.