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Common Stock Warrants | 3 Months Ended
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Mar. 31, 2022
Equity [Abstract] |
Common Stock Warrants | 10. Common Stock Warrants In February 2015 and May 2015, the Company issued warrants to purchase 1,650,098 and 887,536 shares of Series B convertible preferred stock, respectively, at an exercise price of $1.24235 per share (the "Series B Warrants"). Each Series B Warrant was immediately exercisable and expires ten years from the original date of issuance. Pursuant to FASB ASC Topic 480, Distinguishing Liabilities from Equity, the Series B Warrants were classified as a liability and are re-measured to fair value at each balance sheet date and immediately prior to exercise. A total of 12,686 of The Series B Warrants were outstanding as of March 31, 2021. The Series B Warrants were converted into warrants to purchase 12,686 shares of common stock with an exercise price of $17.03 upon the completion of the IPO in November 2021. A total of 12,686 of the common stock warrants remained outstanding at March 31, 2022. The warrants were valued using the Black-Scholes option pricing model. The estimated fair value of the warrants and the significant assumptions used were as follows:
Common Stock Warrants |  | March 31, |
|  | 2022 |
Fair value |  | $ | 22.00 |
Volatility |  |  | 85.12 | %
Expected term (years) |  |  | 2.91 |
Risk free rate |  |  | 2.45 | %
Dividend yield |  |  | 7.00 | %

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