Capital Stock	12 Months Ended
Dec. 31, 2019
Capital Stock
Capital Stock	9. Capital Stock Class A and Class B Common Stock On June 2, 2019 the board of directors of the Company authorized the issuance of 650,000,000 shares of Class A common stock, $0.0001 par value per share, 50,000,000 shares of Class B common stock, $0.0001 par value per share and 300,000,000 shares of preferred stock, $0.0001 par value per share, upon the filing of the Company’s Amended and Restated Certificate of Incorporation in connection with the reverse stock split. Each holder of Class A common stock will be entitled to one vote and each holder of Class B common stock is not entitled to vote except as may be required by law and shall not be entitled to vote on the election of directors at any time. Convertible Preferred Stock Warrant Upon the IPO, the 49,997 preferred stock warrants were revalued and converted to common stock warrants of Class A common stock shares and the warrant liability of $0.5 million was reclassified to additional paid-in capital as a result of the conversion. The warrants were not subject to further remeasurement for fair value. The balances of the preferred stock warrant liabilities were zero and $0.4 million, respectively, as of December 31, 2019 and 2018. Common Stock Warrant In connection with the issuance of Series A in August 2015, the Company issued a warrant to purchase an aggregate of 62,936 shares of common stock at $0.0001 per share. The warrant was immediately exercisable and expires, if not exercised, in August 2025. At issuance, the fair value of the warrant was determined to be $41,509, which was recorded as a Series A preferred stock issuance cost and additional paid-in capital. The warrant was exercised in full during the year ended December 31, 2019 and the Company issued 62,936 shares of Class A common stock upon such exercise.

9. Capital Stock

Class A and Class B Common Stock

On June 2, 2019 the board of directors of the Company authorized the issuance of 650,000,000 shares of Class A common stock, $0.0001 par value per share, 50,000,000 shares of Class B common stock, $0.0001 par value per share and 300,000,000 shares of preferred stock, $0.0001 par value per share, upon the filing of the Company’s Amended and Restated Certificate of Incorporation in connection with the reverse stock split. Each holder of Class A common stock will be entitled to one vote and each holder of Class B common stock is not entitled to vote except as may be required by law and shall not be entitled to vote on the election of directors at any time.

Convertible Preferred Stock Warrant

Upon the IPO, the 49,997 preferred stock warrants were revalued and converted to common stock warrants of Class A common stock shares and the warrant liability of $0.5 million was reclassified to additional paid-in capital as a result of the conversion. The warrants were not subject to further remeasurement for fair value. The balances of the preferred stock warrant liabilities were zero and $0.4 million, respectively, as of December 31, 2019 and 2018.

Common Stock Warrant

In connection with the issuance of Series A in August 2015, the Company issued a warrant to purchase an aggregate of 62,936 shares of common stock at $0.0001 per share. The warrant was immediately exercisable and expires, if not exercised, in August 2025. At issuance, the fair value of the warrant was determined to be $41,509, which was recorded as a Series A preferred stock issuance cost and additional paid-in capital. The warrant was exercised in full during the year ended December 31, 2019 and the Company issued 62,936 shares of Class A common stock upon such exercise.