Stockholders' equity

12 Months Ended

Dec. 31, 2013

Stockholders' equity

Stockholders' equity

10. Stockholders' equity

• Convertible preferred stock

        Each share of Series A, Series A-2, Series B and Series C convertible preferred stock was immediately convertible, at the holder's option, into shares of common stock based on the formula of the issuance price divided by the conversion price. The conversion price was $3.00 for Series A and B convertible preferred stock, $4.026072935 for Series A-2 convertible preferred stock and $4.95835 for Series C convertible preferred stock. Each share of Series A and Series B convertible preferred stock was convertible into one share of common stock. Series A-2 convertible preferred stock was convertible into shares of common stock as obtained by multiplying the number of shares of the convertible stock by $4.30 and dividing the result by the conversion price of $4.026072935 per share, which approximates a 1 for 1.07 shares of common stock conversion rate. Series C convertible preferred stock was convertible into shares of common stock as obtained by multiplying the number of shares of the convertible stock by $5.95 and dividing the result by the conversion price of $4.95835 per share, which approximates a 1 for 1.2 shares of common stock conversion rate. Conversion of each share of Series A, Series A-2, Series B and Series C convertible preferred stock was automatic upon the completion of our IPO.

        The holders of the Series A, Series A-2, Series B and Series C convertible preferred stock were also entitled to receive cumulative dividends, whether or not earned or declared, out of funds legally available therefore, at the rate of $0.15 per share per annum for the Series A and Series B convertible preferred stock, $0.215 for the Series A-2 convertible preferred stock and $0.2975 for the Series C convertible preferred stock (the "accruing dividends"). Accruing dividends accrued on each share of convertible preferred stock from the date of issuance until the earlier of (i) a liquidation, dissolution or winding up of the company, including an acquisition, consolidation or merger, or the sale of all or substantially all of the assets of the company (a "liquidation event") and (ii) the date of redemption. We accrued dividends in the year ended December 31, 2011, which were accreted in the respective carrying values of the convertible preferred stock before they were converted into common stock.

• Reserve for unissued shares

        At December 31, 2013 and 2012, we are authorized to issue up to 100,000,000 shares of common stock. We are required to reserve and keep available out of our authorized but unissued shares of common stock such number of shares sufficient to effect the exercise of all outstanding common stock warrants, plus shares granted and available for grant under our Amended and Restated 2001 Stock Incentive Plan (the "2001 Plan") and 2011 Equity Incentive Plan (the "2011 Plan").

        The amount of such shares of common stock reserved for these purposes is as follows:

	December 31, 2013		December 31, 2012
	(in thousands)
Outstanding stock options under the 2001 Plan		1,859		2,345
Outstanding stock options under the 2011 Plan		3,096		2,700
Outstanding RSUs under the 2011 Plan		753		—
Shares available for grant under the 2011 Plan		3,259		2,811
Total		8,967		7,856

• Note receivable from stockholder

        During 2002, we granted 290,000 shares of restricted common stock to an officer at the deemed fair value of $0.30 per share in exchange for cash proceeds of approximately $9 and issuance of a partial recourse note ("Note") of approximately $78 payable with an interest rate equal to the applicable federal rate. On January 11, 2011, we forgave the Note and the principal and interest outstanding of $103 was expensed as compensation. Interest accrued on the Note, and was included in interest and other income (expense), net in the accompanying consolidated statements of operations.

• Treasury stock

        On July 29, 2011, we approved the retirement of all 1,256,608 outstanding shares of treasury stock. The treasury stock, at cost, of $4,575 was transferred to additional paid-in capital in the accompanying consolidated statements of convertible preferred stock and stockholder's equity (deficit).

• Common stock warrants

        On June 28, 2011, our 26,322 common stock warrants outstanding were exercised into 21,525 shares of common stock on a net exercise basis.