Redeemable Convertible Preferred Stock	12 Months Ended
Dec. 31, 2021
Redeemable Convertible Preferred Stock
Redeemable Convertible Preferred Stock	17. Redeemable Convertible Preferred Stock Series E Preferred Stock In November 2018, the Company issued an aggregate of 35,000 shares of the Company’s Series E Preferred Stock in a private placement to certain accredited investors in reliance on Section 4(a)(2) of the Securities Act. The Company received net proceeds of approximately $30.9 million, after deducting placement agent fees and expenses payable by the Company. The Company is required to redeem the Series E Preferred Stock in thirteen monthly installments in the amount of $2.7 million each from May 2019 through May 2020. The Company had no shares of Series E Preferred Stock outstanding at December 31, 2021 and 2020, as the Series E Preferred Stock was fully converted by early 2020. During 2019, certain conversions of the Series E preferred stock resulted in a deemed dividend of approximately $1.8 million that is reflected on the Company’s consolidated statement of operations as Preferred stock dividends declared, deemed dividends and accretion of discount. Series C Preferred Stock There were no shares of Series C Preferred Stock that were outstanding at December 31, 2021 or 2020. In April 2020, 870 shares of Series C Preferred Stock were converted to 923,819 shares of common stock. In May 2020, the remaining the 1,750 shares of Series C Preferred Stock were converted into 1,858,256 shares of common stock.

Redeemable Convertible Preferred Stock

12 Months Ended

Dec. 31, 2021

Redeemable Convertible Preferred Stock

17. Redeemable Convertible Preferred Stock

Series E Preferred Stock

In November 2018, the Company issued an aggregate of 35,000 shares of the Company’s Series E Preferred Stock in a private placement to certain accredited investors in reliance on Section 4(a)(2) of the Securities Act. The Company received net proceeds of approximately $30.9 million, after deducting placement agent fees and expenses payable by the Company. The Company is required to redeem the Series E Preferred Stock in thirteen monthly installments in the amount of $2.7 million each from May 2019 through May 2020. The Company had no shares of Series E Preferred Stock outstanding at December 31, 2021 and 2020, as the Series E Preferred Stock was fully converted by early 2020.

During 2019, certain conversions of the Series E preferred stock resulted in a deemed dividend of approximately $1.8 million that is reflected on the Company’s consolidated statement of operations as Preferred stock dividends declared, deemed dividends and accretion of discount.

Series C Preferred Stock

There were no shares of Series C Preferred Stock that were outstanding at December 31, 2021 or 2020.

In April 2020, 870 shares of Series C Preferred Stock were converted to 923,819 shares of common stock. In May 2020, the remaining the 1,750 shares of Series C Preferred Stock were converted into 1,858,256 shares of common stock.