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Redeemable Convertible Preferred Stock | 12 Months Ended
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Dec. 31, 2016
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Redeemable Convertible Preferred Stock | 9. Redeemable Convertible Preferred Stock In April 2016, 1,999,998 shares of Series B redeemable convertible preferred stock were issued in connection with the exercise of warrants for cash proceeds of $20,000. Following the closing of the IPO, all outstanding shares of the redeemable convertible preferred stock converted into 8,577,571 shares of common stock and the related carrying value was reclassified to common stock and additional paid-in capital. There were no shares of redeemable convertible preferred stock outstanding as of December 31, 2016. The table below provides information on the Company’s redeemable convertible preferred stock as of December 31, 2015 (in thousands, except shares and original issue price):
|  |  |  |  | Shares |  |  |  |  |  |  |
| Original Issue Price |  |  | Authorized |  |  | Issued and Outstanding |  |  | Carrying Value |  |  | Aggregate Liquidation Preference |
Series A |  | $ | 1.00 |  |  |  | 6,037,500 |  |  |  | 6,037,500 |  |  | $ | 1,751 |  |  | $ | 6,038 |
Series B |  | $ | 0.50 |  |  |  | 40,000,000 |  |  |  | 36,000,000 |  |  |  | 18,825 |  |  |  | 18,000 |
Series C |  | $ | 0.4979 |  |  |  | 80,337,411 |  |  |  | 35,147,617 |  |  |  | 16,420 |  |  |  | 17,500 |
Total redeemable convertible preferred stock |  |  |  |  |  |  | 126,374,911 |  |  |  | 77,185,117 |  |  | $ | 36,996 |  |  | $ | 41,538 |
As only the passage of time was required for Series A, B and C to become redeemable, the Company was accreting the carrying value of Series A, B and C to their redemption value over the period from the respective date of issuance to July 2022, (the earliest redemption date) up to the IPO date. In the event of a change of control of the Company, proceeds would be distributed in accordance with the liquidation preferences set forth in the Company’s Amended and Restated Certificate of Incorporation unless the holders of redeemable convertible preferred stock had converted their redeemable convertible preferred stock into shares of common stock. Therefore, redeemable convertible preferred stock was classified outside of stockholders’ equity (deficit) on the consolidated balance sheets, as Series A, B and C redeemable convertible preferred stock can be redeemed and as events triggering the liquidation preferences were not solely within the Company’s control. The Company recorded $558,000, $75,000, and $146,000 for the accretion of the redeemable convertible preferred stock during the years ended December 31, 2016, 2015, and 2014, respectively. The accretion was recorded as an offset to the additional paid in capital until such balance was depleted and any remaining accretion was recorded to accumulated deficit.

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