Stockholders' Equity

12 Months Ended

Dec. 31, 2011

Stockholders' Equity [Abstract]

Stockholders' Equity

6. STOCKHOLDERS' EQUITY

Common Stock

On June 22, 2011, the shareholders of the Company approved a reduction of the shares of common stock authorized with a par value of $0.001 by 40,000,000, from 85,000,000 to 45,000,000. As of December 31, 2011 the Company had reserved 2,093,108 shares of common stock for issuance upon the exercise of outstanding common stock options. Also, 2,260,008 shares of the Company's common stock were reserved for future grants of stock options (or other similar equity instruments) under the Company's 2007 Stock Incentive Plan (the "2007 Plan") as of December 31, 2011. In addition, 281,561 shares of the Company's common stock were reserved for future exercise of outstanding warrants as of December 31, 2011.

On June 21, 2010, the Company completed a public offering of common stock in which a total of 3,029,100 shares were sold at a price of $30.00 per share. The Company sold 2,195,100 shares of common stock, including 395,100 shares pursuant to the full exercise of the underwriter's over-allotment option, and certain stockholders of the Company sold 834,000 shares of common stock. The Company raised a total of $65.9 million in gross proceeds from the offering, or approximately $61.7 million in net proceeds after deducting the underwriting discount and commissions of $3.5 million and estimated other offering costs of approximately $712,000. The Company did not receive any of the proceeds from the sale of common stock by the selling stockholders.

Warrants

At December 31, 2011 and 2010, the Company had outstanding 267,826 warrants to purchase common stock at an exercise price of $3.65 per share. The warrants were issued in conjunction with the issuance of convertible promissory notes issued by the Company to investors from August 2005 through October 2005. During 2009, 47,863 of these warrants were exercised on a "net exercise" basis, resulting in the issuance of 38,091 shares of common stock. The warrants are immediately exercisable and expire 10 years from the date of issuance.

At December 31, 2011 and 2010 the Company had outstanding 13,735 warrants to purchase common stock at an exercise price of $7.28 per share. The warrants were issued in 2002 in conjunction with the procurement of loans. The warrants are immediately exercisable and expire 10 years from the date of issuance.

During 2009, 7,281 of the warrants issued in conjunction with a 2006 loan guarantee were exercised on a "net exercise" basis, resulting in the issuance of 5,794 shares of common stock.

Treasury Stock

On August 4, 2011, the Company authorized a stock repurchase program to purchase up to $25.0 million of its common stock over a period of two years. The stock repurchase program authorizes the Company to repurchase its shares of common stock in the open market at times and prices considered appropriate by the Company depending upon prevailing market conditions and other corporate considerations. The treasury shares are accounted for using the cost method whereby the entire cost of the acquired stock is recorded as treasury stock. For the twelve months ended December 31, 2011, the Company repurchased 524,869 shares at an average price of $12.36 for $6.5 million.

In November 2008, the Company authorized a stock repurchase program to purchase up to $15.0 million of common stock over a period of two years. The stock repurchase program authorized the Company to repurchase shares of its common stock in the open market at times and prices considered appropriate by the Company depending upon prevailing market conditions and other corporate considerations. The treasury shares are accounted for using the cost method whereby the entire cost of the acquired stock is recorded as treasury stock. During 2010, no shares were repurchased and the plan expired on its terms on December 31, 2010.