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Stockholders' Equity | 9 Months Ended
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Sep. 30, 2025
Stockholders' Equity |
Stockholders' Equity |
11. | Stockholders’ Equity
As of September 30, 2025, the Company was authorized to issue 50,000,000 shares of preferred stock, 492,815,092 shares of voting common stock and 7,184,908 shares of non-voting common stock, all with par values of $0.0001 per share. As of September 30, 2025, there were no shares of preferred stock issued or outstanding, 97,174,231 shares of voting common stock issued and outstanding and 7,184,908 shares of non-voting common stock issued and outstanding. The holders of voting and non-voting common stock have the same rights except that non-voting common stock does not have voting rights, except as may be required by law. Each holder of non-voting common stock has a right to convert each share of non-voting common stock to one share of voting common stock subject to the following limitations. At any time following the Company’s registration of any class of equity securities under the Exchange Act, the holders of shares of non-voting common stock may not convert a number of shares of non-voting common stock into shares of voting common stock in excess of that number of shares of non-voting common stock which would cause the holder thereof to beneficially own (for purposes of Section 13(d) of the Exchange Act), in excess of 4.99% of the total number of issued and outstanding shares of voting common stock. Such maximum percentage may be increased or decreased to such other percentage as any holder of outstanding shares of non-voting common stock may designate in writing (in the case of an increase upon 61 days’ prior written notice). Common stock reserved for issuance, on an as-converted basis, consisted of the following as of September 30, 2025 and December 31, 2024: ​
​ | ​ | ​ | ​ | ​
​ |  | September 30, |  | December 31,
​ | ​ | 2025 | ​ | 2024
Stock options issued and outstanding |  | 20,090,359 |  | 9,458,788
RSUs issued and outstanding | ​ | 2,670,905 | ​ | —
Shares available for grant under the 2024 Equity Incentive Plan | ​ | 930,301 | ​ | 6,893,517
Shares available for grant under the 2024 Employee Stock Purchase Plan | ​ | 1,009,440 | ​ | 650,000
Shares available for grant under the ACELYRIN, Inc. 2023 Equity Incentive Plan | ​ | 6,448,105 | ​ | —
Shares available for grant under the 2024 Performance Option Plan | ​ | 199,856 | ​ | 92,800
Total |  | 31,348,966 |  | 17,095,105
​ Common Stock Issued to Executives In February 2021, the Company issued 100,532 shares of restricted common stock to two executives at a purchase price of $0.94 per share. The shares vested over a four-year period with a one-year cliff. While the shares were unvested, the holders had voting and dividends rights and the Company had the right to repurchase unvested shares of common stock at the price paid by the holder in the event of termination of the holder’s continuous status as a service provider. The Company estimated the fair value of the restricted stock awards based on the fair value of common stock at the grant dates. The expense was recognized ratably over the vesting terms. The Company recognized less than $0.1 million of stock-based compensation expense for the three and nine months ended September 30, 2025 and 2024. The following table summarizes the activity for the Company’s restricted common stock for the nine months ended September 30, 2025: ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | Weighted-
​ | ​ | ​ | ​ | Average
​ | ​ | Number of | ​ | Grant Date
​ | ​ | Shares | ​ | Fair Value
Unvested as of December 31, 2024 |  | 2,583 | ​ | $ | 2.90
Vested |  | (2,583) | ​ | $ | 2.90
Unvested as of September 30, 2025 |  | — | ​ | $ | —
​

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