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Reserved for Future Issuance (Details) | Sep. 30, 2021 shares | Jun. 02, 2021 | Dec. 31, 2020 shares
--- | --- | --- | ---
Common Stock |  |  |
Number of shares reserved for future issuance | 8,392,932 |  | 1,607,657
Series X redeemable convertible preferred stock |  |  |
Common Stock |  |  |
Number of shares reserved for future issuance | 5,242,501 |  |
Preferred stock, outstanding (in shares) | 31,455 |  | 0
Number of shares of common stock into which each share of Series X Preferred Stock may be converted | 166.67 | 166.67 |
Warrants for the purchase of common stock |  |  |
Common Stock |  |  |
Number of shares reserved for future issuance | 1,530,380 |  | 1,032,291
Options outstanding to purchase Common Stock |  |  |
Common Stock |  |  |
Number of shares reserved for future issuance | 1,334,399 |  | 227,846
Options available for future issuance to purchase Common Stock |  |  |
Common Stock |  |  |
Number of shares reserved for future issuance | 254,748 |  | 322,695
Shares reserved for the employee stock purchase plan |  |  |
Common Stock |  |  |
Number of shares reserved for future issuance | 30,904 |  | 24,825

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