Warrants	3 Months Ended
Mar. 31, 2014
Warrants
Warrants	10. Warrants In connection with the line of credit secured in April 2012, the Company issued a warrant to purchase 12,797 shares of the Company’s Series D redeemable convertible preferred stock with an exercise price of $7.81 per share. The warrant was valued at $74 thousand on the date of grant and at $19 thousand and $119 thousand at December 31, 2013 and March 31, 2014, respectively. The warrant remained outstanding as of March 31, 2014 and will expire in 2022. In connection with the line of credit secured in December 2013, the Company issued a warrant to purchase 71,021 shares of the Company’s Series D redeemable convertible preferred stock with an exercise price of $7.81 per share. The warrant was valued at $107 thousand and $695 thousand as of December 31, 2013 and March 31, 2014, respectively. The warrant remained outstanding as of March 31, 2014 and will expire in 2023. Each of the Series D warrants are classified as a liability in the accompanying unaudited condensed consolidated balance sheets and adjusted to fair value due to the fact that at March 31, 2014, they were exercisable into redeemable convertible preferred securities. The inputs to the fair value model for the warrants are considered Level 3 inputs under ASC 820, Fair Value Measurements and Disclosures. All changes in the fair value of the warrants are recorded as a component of interest expense. The Company recorded a reduction of interest expense of $33 thousand for the year ended December 31, 2013, and interest expense of $688 thousand for the three months ended March 31, 2014, related to the fair value adjustment of the warrants. On April 2, 2014, upon closing of the Company’s IPO, the warrants to purchase Series D redeemable convertible preferred stock converted into warrants to purchase common stock and the liability at its then fair value of $814 thousand was reclassified to additional paid in capital.

10. Warrants

In connection with the line of credit secured in April 2012, the Company issued a warrant to purchase 12,797 shares of the Company’s Series D redeemable convertible preferred stock with an exercise price of $7.81 per share. The warrant was valued at $74 thousand on the date of grant and at $19 thousand and $119 thousand at December 31, 2013 and March 31, 2014, respectively. The warrant remained outstanding as of March 31, 2014 and will expire in 2022.

In connection with the line of credit secured in December 2013, the Company issued a warrant to purchase 71,021 shares of the Company’s Series D redeemable convertible preferred stock with an exercise price of $7.81 per share. The warrant was valued at $107 thousand and $695 thousand as of December 31, 2013 and March 31, 2014, respectively. The warrant remained outstanding as of March 31, 2014 and will expire in 2023.

Each of the Series D warrants are classified as a liability in the accompanying unaudited condensed consolidated balance sheets and adjusted to fair value due to the fact that at March 31, 2014, they were exercisable into redeemable convertible preferred securities.

The inputs to the fair value model for the warrants are considered Level 3 inputs under ASC 820, Fair Value Measurements and Disclosures. All changes in the fair value of the warrants are recorded as a component of interest expense. The Company recorded a reduction of interest expense of $33 thousand for the year ended December 31, 2013, and interest expense of $688 thousand for the three months ended March 31, 2014, related to the fair value adjustment of the warrants. On April 2, 2014, upon closing of the Company’s IPO, the warrants to purchase Series D redeemable convertible preferred stock converted into warrants to purchase common stock and the liability at its then fair value of $814 thousand was reclassified to additional paid in capital.