ALMS

SEC source: 0001415889-25-020804 · form4-07312025_090708.xml · derivative · entry 5

Goldstein David M · CIK 0001751719 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 107,950

Underlying: Common Stock · 107,950 shares

Expires 2035-07-28

F6 · derivative.exercise_date: 25% of the shares underlying this option vest on July 29, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

SEC source: 0001415889-25-020804 · form4-07312025_090708.xml · nonDerivative · entry 1

Goldstein David M · CIK 0001751719 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 29,115

F1 · shares: Represents shares of common stock issuable upon settlement of a restricted stock unit ("RSU") grant. 25% of the shares underlying this RSU vest on August 1, 2026, and the remaining shares vest in equal quarterly installments thereafter over the following 12 quarters, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

F2 · balance_after: Includes 2,115 shares acquired on May 20, 2025 under the Issuer's 2024 Employee Stock Purchase Plan.

SEC source: 0001415889-25-020803 · form4-07312025_090706.xml · derivative · entry 2

Drappa Jorn · CIK 0001789317 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 101,850

Underlying: Common Stock · 101,850 shares

Expires 2035-07-28

F3 · derivative.exercise_date: 25% of the shares underlying this option vest on July 29, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

SEC source: 0001415889-25-020803 · form4-07312025_090706.xml · nonDerivative · entry 1

Drappa Jorn · CIK 0001789317 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 28,450

F1 · shares: Represents shares of common stock issuable upon settlement of a restricted stock unit ("RSU") grant. 25% of the shares underlying this RSU vest on August 1, 2026, and the remaining shares vest in equal quarterly installments thereafter over the following 12 quarters, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

F2 · balance_after: Includes 3,000 shares acquired on May 20, 2025 under the Issuer's 2024 Employee Stock Purchase Plan.

SEC source: 0001415889-25-020801 · form4-07312025_090701.xml · derivative · entry 4

Babler Martin · CIK 0001435618 · Director · President, CEO and Chairman

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 150,000

Underlying: Common Stock · 150,000 shares

Expires 2035-07-28

F3 · derivative.exercise_date: 25% of the shares underlying this option vest on July 29, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

SEC source: 0001415889-25-020801 · form4-07312025_090701.xml · derivative · entry 3

Babler Martin · CIK 0001435618 · Director · President, CEO and Chairman

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 662,000

Underlying: Common Stock · 662,000 shares

Expires 2035-07-28

F3 · derivative.exercise_date: 25% of the shares underlying this option vest on July 29, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

SEC source: 0001415889-25-019705 · form4-07142025_080702.xml · derivative · entry 1

Pangali Sanam · CIK 0002023806 · Chief Legal Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 100,000 shares

Expires 2036-07-09

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on July 4, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's Continuous Service (as defined in the Issuer's 2024 Equity Incentive Plan) to the Issuer on each such vesting date.

SEC source: 0001415889-25-014559 · form4-05242025_120550.xml · nonDerivative · entry 1

AKKARAJU SRINIVAS · CIK 0001253170 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Samsara BioCapital, L.P.

Disclosed balance after: 4,801,370

F1 · shares: On May 21, 2025, pursuant to the Agreement and Plan of Merger, dated as of February 6, 2025 and amended on April 21, 2025, by and among the Issuer, ACELYRIN, Inc. ("ACELYRIN"), and Arrow Merger Sub, Inc., a direct wholly owned subsidiary of the Issuer ("Merger Sub"), Merger Sub merged with and into ACELYRIN with ACELYRIN continuing as the surviving corporation and as a wholly owned subsidiary of the Issuer (the "Merger"). Each share of ACELYRIN common stock was exchanged for 0.4814 shares of the Issuer's common stock.

F2 · price: Received in exchange for 2,523,022 shares of common stock of ACELYRIN in connection with the Merger (as described in footnote 1) on May 21, 2025.

F3 · ownership.nature: Shares are held directly by Samsara BioCapital, L.P. ("Samsara LP"). Samsara BioCapital GP, LLC ("Samsara GP") is the general partner of Samsara LP. The Reporting Person, as the managing member of Samsara GP, shares voting and investment authority over the shares held by Samsara LP. The Reporting Person disclaims beneficial ownership in these shares except to the extent of his pecuniary interest therein.

SEC source: 0000902664-25-002532 · ownership.xml · nonDerivative · entry 1

AyurMaya Capital Management Company, LP · CIK 0001975990 · Director · 10% owner · See Remarks

GOEL DAVID E. · CIK 0001548144 · Director · 10% owner · See Remarks

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 15,139,707

F1 · kind: Pursuant to the Agreement and Plan of Merger, as amended on April 20, 2025, by and among ACELYRIN, Inc., a Delaware corporation ("ACELYRIN") and Alumis Inc., a Delaware corporation (the "Issuer") and the other parties thereto (the "Merger Agreement"), the shares of Common Stock were issued to the AyurMaya Fund (as defined below) in exchange for 9,334,735 shares of ACELYRIN common stock on the effective date of the merger contemplated by the Merger Agreement.

F2 · shares: Reflects the estimated number of shares of Common Stock to be issued to the AyurMaya Fund (as defined below) pursuant to the Merger Agreement. The Reporting Persons will file an amendment to this Form 4 to the extent the actual number of shares of Common Stock issued differs in any material respect from the number reported in column (4).

F1 · price: Pursuant to the Agreement and Plan of Merger, as amended on April 20, 2025, by and among ACELYRIN, Inc., a Delaware corporation ("ACELYRIN") and Alumis Inc., a Delaware corporation (the "Issuer") and the other parties thereto (the "Merger Agreement"), the shares of Common Stock were issued to the AyurMaya Fund (as defined below) in exchange for 9,334,735 shares of ACELYRIN common stock on the effective date of the merger contemplated by the Merger Agreement.

F3 · ownership.nature: The securities reported herein are held by AyurMaya Capital Management Fund, LP (the "AyurMaya Fund"). AyurMaya Capital Management Company, LP (the "Investment Manager"), a Delaware limited partnership, is the investment advisor to the AyurMaya Fund. Mr. David E. Goel ("Mr. Goel", and together with the Investment Manager, the "Reporting Persons"), serves as the managing member of AyurMaya Capital Management Company GP, LLC, the general partner of the Investment Manager.

F4 · ownership.nature: The filing of this statement shall not be deemed an admission that either of the Reporting Persons is the beneficial owner of the securities reported herein for purposes of Section 16 of the Securities Act of 1934, as amended, or otherwise. Each of the Reporting Persons expressly disclaims beneficial ownership of the securities reported herein except to the extent of its or his pecuniary interest therein, if any.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · derivative · entry 6

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,528

Underlying: Class A Common Stock · 19,528 shares

Expires 2031-07-25

F9 · security: Received in the Merger in exchange for an employee stock option to acquire 40,567 shares of ACELYRIN common stock for $0.7683 per share.

F4 · derivative.exercise_price: Pursuant to the Merger Agreement, at the Effective Time each stock option that was outstanding and unexercised immediately prior to the Effective Time with a per share exercise price of $18.00 or less was assumed by Issuer and converted into an option to purchase a number of shares of Issuer Common Stock equal to (i) the number of shares subject to the option immediately prior to the Effective Time, multiplied by (ii) the Exchange Ratio, with any fractional shares rounded down to the nearest whole share, which stock option shall have an exercise price equal to (i) the per share exercise price for shares subject to the corresponding ACELYRIN stock option immediately prior to the Effective Time, divided by (ii) the Exchange Ratio, rounded up to the nearest whole cent.

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F5 · derivative.exercise_date: Stock Option is fully vested and exercisable.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · derivative · entry 5

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,804

Underlying: Class A Common Stock · 13,804 shares

Expires 2032-11-20

F8 · security: Received in the Merger in exchange for an employee stock option to acquire 28,675 shares of ACELYRIN common stock for $5.8766 per share.

F4 · derivative.exercise_price: Pursuant to the Merger Agreement, at the Effective Time each stock option that was outstanding and unexercised immediately prior to the Effective Time with a per share exercise price of $18.00 or less was assumed by Issuer and converted into an option to purchase a number of shares of Issuer Common Stock equal to (i) the number of shares subject to the option immediately prior to the Effective Time, multiplied by (ii) the Exchange Ratio, with any fractional shares rounded down to the nearest whole share, which stock option shall have an exercise price equal to (i) the per share exercise price for shares subject to the corresponding ACELYRIN stock option immediately prior to the Effective Time, divided by (ii) the Exchange Ratio, rounded up to the nearest whole cent.

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F5 · derivative.exercise_date: Stock Option is fully vested and exercisable.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · derivative · entry 4

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,499

Underlying: Class A Common Stock · 41,499 shares

Expires 2032-11-20

F7 · security: Received in the Merger in exchange for an employee stock option to acquire 86,206 shares of ACELYRIN common stock for $5.8766 per share.

F4 · derivative.exercise_price: Pursuant to the Merger Agreement, at the Effective Time each stock option that was outstanding and unexercised immediately prior to the Effective Time with a per share exercise price of $18.00 or less was assumed by Issuer and converted into an option to purchase a number of shares of Issuer Common Stock equal to (i) the number of shares subject to the option immediately prior to the Effective Time, multiplied by (ii) the Exchange Ratio, with any fractional shares rounded down to the nearest whole share, which stock option shall have an exercise price equal to (i) the per share exercise price for shares subject to the corresponding ACELYRIN stock option immediately prior to the Effective Time, divided by (ii) the Exchange Ratio, rounded up to the nearest whole cent.

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F5 · derivative.exercise_date: Stock Option is fully vested and exercisable.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · derivative · entry 3

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,189

Underlying: Class A Common Stock · 11,189 shares

Expires 2033-05-03

F6 · security: Received in the Merger in exchange for an employee stock option to acquire 23,243 shares of ACELYRIN common stock for $18.00 per share.

F4 · derivative.exercise_price: Pursuant to the Merger Agreement, at the Effective Time each stock option that was outstanding and unexercised immediately prior to the Effective Time with a per share exercise price of $18.00 or less was assumed by Issuer and converted into an option to purchase a number of shares of Issuer Common Stock equal to (i) the number of shares subject to the option immediately prior to the Effective Time, multiplied by (ii) the Exchange Ratio, with any fractional shares rounded down to the nearest whole share, which stock option shall have an exercise price equal to (i) the per share exercise price for shares subject to the corresponding ACELYRIN stock option immediately prior to the Effective Time, divided by (ii) the Exchange Ratio, rounded up to the nearest whole cent.

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F5 · derivative.exercise_date: Stock Option is fully vested and exercisable.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · derivative · entry 2

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 44,364

Underlying: Class A Common Stock · 44,364 shares

Expires 2034-06-06

F3 · security: Received in the Merger in exchange for an employee stock option to acquire 92,158 shares of ACELYRIN common stock for $4.46 per share.

F4 · derivative.exercise_price: Pursuant to the Merger Agreement, at the Effective Time each stock option that was outstanding and unexercised immediately prior to the Effective Time with a per share exercise price of $18.00 or less was assumed by Issuer and converted into an option to purchase a number of shares of Issuer Common Stock equal to (i) the number of shares subject to the option immediately prior to the Effective Time, multiplied by (ii) the Exchange Ratio, with any fractional shares rounded down to the nearest whole share, which stock option shall have an exercise price equal to (i) the per share exercise price for shares subject to the corresponding ACELYRIN stock option immediately prior to the Effective Time, divided by (ii) the Exchange Ratio, rounded up to the nearest whole cent.

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F5 · derivative.exercise_date: Stock Option is fully vested and exercisable.

SEC source: 0001415889-25-014422 · form4-05232025_040512.xml · nonDerivative · entry 1

Machado Patrick · CIK 0001311210 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Trust

Disclosed balance after: 7,064

F1 · price: On February 6, 2025, the Issuer entered into an Agreement and Plan of Merger (as amended on April 20, 2025, the "Merger Agreement") with ACELYRIN, Inc., a Delaware corporation ("ACELYRIN"), and Arrow Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Issuer ("Merger Sub"). Pursuant to the Merger Agreement, on May 21, 2025, Merger Sub merged with and into ACELYRIN (the "Merger"), with ACELYRIN surviving as a wholly owned subsidiary of Issuer. At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.00001 per share, of ACELYRIN issued and outstanding was converted into the right to receive 0.4814 (the "Exchange Ratio") shares of voting common stock of Issuer, par value $0.0001 per share, and cash in lieu of any fractional shares.

F2 · ownership.nature: Shares held directly by Patrick Machado Revocable Trust, Patrick Machado, TEE, for which the Reporting Person serves as trustee.

SEC source: 0001104659-25-045221 · tm2514241-2_4seq1.xml · nonDerivative · entry 2

Foresite Labs, LLC · CIK 0002027905 · 10% owner

Foresite Labs Affiliates 2021, LLC · CIK 0002028005 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,247,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Each of the Reporting Persons disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, other than Fund VI, disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001104659-25-045219 · tm2514241-1_4seq1.xml · nonDerivative · entry 2

Foresite Capital Management VI LLC · CIK 0002013341 · 10% owner

Foresite Capital Management V, LLC · CIK 0001792206 · 10% owner

Foresite Capital Fund V, L.P. · CIK 0001792204 · 10% owner

Foresite Capital Opportunity Management V, LLC · CIK 0001792207 · 10% owner

Foresite Capital Opportunity Fund V, L.P. · CIK 0001792205 · 10% owner

Foresite Capital Fund VI LP · CIK 0001932516 · 10% owner

Labs Co-Invest V, LLC · CIK 0001810063 · 10% owner

Foresite Labs Management I, LLC · CIK 0001848577 · 10% owner

Foresite Labs Fund I, L.P. · CIK 0001848472 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,247,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Each of the Reporting Persons disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, other than Fund VI, disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001104659-25-045222 · tm2514241-3_4seq1.xml · nonDerivative · entry 2

Tananbaum James B. · CIK 0001581754 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,247,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Tananbaum disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001415889-25-012166 · form4-05062025_100542.xml · nonDerivative · entry 3

AKKARAJU SRINIVAS · CIK 0001253170 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Samsara BioCapital, L.P.

Disclosed balance after: 3,586,788

F4 · price: The price reported in Column 4 is a weighted average price. These securities were purchased in multiple transactions at prices ranging from $5.19 to $5.48 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities purchased at each separate price within the range set forth in this footnote.

F2 · ownership.nature: Shares are held directly by Samsara BioCapital, L.P. ("Samsara LP"). Samsara BioCapital GP, LLC ("Samsara GP") is the general partner of Samsara LP. The Reporting Person, as the managing member of Samsara GP, shares voting and investment authority over the shares held by Samsara LP. The Reporting Person disclaims beneficial ownership in these shares except to the extent of his pecuniary interest therein.

SEC source: 0001415889-25-012166 · form4-05062025_100542.xml · nonDerivative · entry 2

AKKARAJU SRINIVAS · CIK 0001253170 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Samsara BioCapital, L.P.

Disclosed balance after: 3,564,786

F3 · price: The price reported in Column 4 is a weighted average price. These securities were purchased in multiple transactions at prices ranging from $4.19 to $5.1899 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities purchased at each separate price within the range set forth in this footnote.

F2 · ownership.nature: Shares are held directly by Samsara BioCapital, L.P. ("Samsara LP"). Samsara BioCapital GP, LLC ("Samsara GP") is the general partner of Samsara LP. The Reporting Person, as the managing member of Samsara GP, shares voting and investment authority over the shares held by Samsara LP. The Reporting Person disclaims beneficial ownership in these shares except to the extent of his pecuniary interest therein.

SEC source: 0001104659-25-045221 · tm2514241-2_4seq1.xml · nonDerivative · entry 1

Foresite Labs, LLC · CIK 0002027905 · 10% owner

Foresite Labs Affiliates 2021, LLC · CIK 0002028005 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,227,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Each of the Reporting Persons disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, other than Fund VI, disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001104659-25-045219 · tm2514241-1_4seq1.xml · nonDerivative · entry 1

Foresite Capital Management VI LLC · CIK 0002013341 · 10% owner

Foresite Capital Management V, LLC · CIK 0001792206 · 10% owner

Foresite Capital Fund V, L.P. · CIK 0001792204 · 10% owner

Foresite Capital Opportunity Management V, LLC · CIK 0001792207 · 10% owner

Foresite Capital Opportunity Fund V, L.P. · CIK 0001792205 · 10% owner

Foresite Capital Fund VI LP · CIK 0001932516 · 10% owner

Labs Co-Invest V, LLC · CIK 0001810063 · 10% owner

Foresite Labs Management I, LLC · CIK 0001848577 · 10% owner

Foresite Labs Fund I, L.P. · CIK 0001848472 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,227,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Each of the Reporting Persons disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, other than Fund VI, disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001104659-25-045222 · tm2514241-3_4seq1.xml · nonDerivative · entry 1

Tananbaum James B. · CIK 0001581754 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 4,227,670

F1 · ownership.nature: The shares are held of record by Foresite Capital Fund VI, L.P. ("Fund VI"). Foresite Capital Management VI, LLC ("FCM VI") is the general partner of Fund VI and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCM VI, may be deemed to have sole voting and dispositive power over such shares. Tananbaum disclaims the existence of a "group", as defined in Rule 13d-5 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and disclaims beneficial ownership of the shares held by Fund VI, except to the extent of such person's pecuniary interest in such securities.

SEC source: 0001415889-25-012166 · form4-05062025_100542.xml · nonDerivative · entry 1

AKKARAJU SRINIVAS · CIK 0001253170 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Samsara BioCapital, L.P.

Disclosed balance after: 3,426,418

F1 · price: The price reported in Column 4 is a weighted average price. These securities were purchased in multiple transactions at prices ranging from $3.97 to $4.84 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of securities purchased at each separate price within the range set forth in this footnote.

F2 · ownership.nature: Shares are held directly by Samsara BioCapital, L.P. ("Samsara LP"). Samsara BioCapital GP, LLC ("Samsara GP") is the general partner of Samsara LP. The Reporting Person, as the managing member of Samsara GP, shares voting and investment authority over the shares held by Samsara LP. The Reporting Person disclaims beneficial ownership in these shares except to the extent of his pecuniary interest therein.

SEC source: 0001415889-25-010050 · form4-04032025_100437.xml · nonDerivative · entry 2

Colowick Alan · CIK 0001316163 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Revocable Living Trust

Disclosed balance after: 18,404

F3 · price: Price reported is a weighted-average purchase price. The shares were purchased at prices ranging from $7.33 to $7.75. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares purchased at each separate price.

F2 · ownership.nature: Shares are held directly by The Colowick Trust, for which Reporting Person serves as a trustee.

SEC source: 0001415889-25-010050 · form4-04032025_100437.xml · nonDerivative · entry 1

Colowick Alan · CIK 0001316163 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By Revocable Living Trust

Disclosed balance after: 16,104

F1 · price: Price reported is a weighted-average purchase price. The shares were purchased at prices ranging from $6.79 to $7.10. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares purchased at each separate price.

F2 · ownership.nature: Shares are held directly by The Colowick Trust, for which Reporting Person serves as a trustee.

SEC source: 0001415889-25-010049 · form4-04032025_100402.xml · nonDerivative · entry 1

Babler Martin · CIK 0001435618 · Director · President, CEO and Chairman

10b5-1 filing: No plan indicated

Ownership: Indirect · By Trust

Disclosed balance after: 106,454

F1 · price: Price reported is a weighted-average purchase price. The shares were purchased at prices ranging from $6.18 to $6.95. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares purchased at each separate price.

F2 · ownership.nature: Shares are held directly by Martin Babler revocable trust UAD October 25, 2006, for which Reporting Person serves as a trustee.

SEC source: 0001415889-25-004942 · form4-02202025_060215.xml · derivative · entry 1

Richardson Derrick · CIK 0002022896 · SVP, People and Culture

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 50,000

Underlying: Common Stock · 50,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004940 · form4-02202025_060210.xml · derivative · entry 1

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 140,000

Underlying: Common Stock · 140,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004939 · form4-02202025_060208.xml · derivative · entry 1

Klein Sara · CIK 0002022981 · Chief Legal Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 180,000

Underlying: Common Stock · 180,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004958 · form4-02212025_120222.xml · derivative · entry 1

Hardiman Roy C. · CIK 0001506218 · Chief Business & Strategy Ofcr

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 140,000

Underlying: Common Stock · 140,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004941 · form4-02202025_060213.xml · derivative · entry 1

Schroer John R. · CIK 0001744578 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 140,000

Underlying: Common Stock · 140,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004938 · form4-02202025_060206.xml · derivative · entry 1

Drappa Jorn · CIK 0001789317 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 180,000

Underlying: Common Stock · 180,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004936 · form4-02202025_060201.xml · derivative · entry 1

Babler Martin · CIK 0001435618 · Director · President, CEO and Chairman

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 523,000

Underlying: Common Stock · 523,000 shares

Expires 2035-02-17

F1 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-25-004937 · form4-02202025_060203.xml · derivative · entry 3

Goldstein David M · CIK 0001751719 · Chief Scientific Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 180,000

Underlying: Common Stock · 180,000 shares

Expires 2035-02-17

F4 · derivative.exercise_date: 25% of the shares underlying this option vest on February 18, 2026, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 21

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 53,475

Underlying: Common Stock · 53,475 shares

Expires 2034-06-05

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F10 · derivative.exercise_date: 25% of the shares underlying this option vest on June 6, 2025, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 20

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 53,475 shares

Expires 2034-06-05

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F10 · derivative.exercise_date: 25% of the shares underlying this option vest on June 6, 2025, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 19

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 155,304

Underlying: Common Stock · 155,304 shares

Expires 2034-05-05

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F9 · derivative.exercise_date: The option vests in three equal installments, subject to the Issuer's satisfaction of certain performance criteria on each of May 6, 2028, May 6, 2029 and May 6, 2030, and subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 18

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 155,304 shares

Expires 2034-05-05

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F9 · derivative.exercise_date: The option vests in three equal installments, subject to the Issuer's satisfaction of certain performance criteria on each of May 6, 2028, May 6, 2029 and May 6, 2030, and subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 17

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,093

Underlying: Common Stock · 23,093 shares

Expires 2033-10-08

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F8 · derivative.exercise_date: 25% of the shares underlying this option vest on October 9, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 16

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 23,093 shares

Expires 2033-10-08

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F8 · derivative.exercise_date: 25% of the shares underlying this option vest on October 9, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 15

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,834

Underlying: Common Stock · 12,834 shares

Expires 2033-06-22

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F7 · derivative.exercise_date: 25% of the shares underlying this option vested on May 22, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 14

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 12,834 shares

Expires 2033-06-22

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F7 · derivative.exercise_date: 25% of the shares underlying this option vested on May 22, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 13

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 128,342

Underlying: Common Stock · 128,342 shares

Expires 2032-01-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F6 · derivative.exercise_date: 33% of the shares underlying this option vested on January 27, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 48 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 12

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 128,342 shares

Expires 2032-01-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F6 · derivative.exercise_date: 33% of the shares underlying this option vested on January 27, 2024, and the remaining shares vest in equal monthly installments thereafter over the following 48 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 11

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 130,481

Underlying: Common Stock · 130,481 shares

Expires 2032-01-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F5 · derivative.exercise_date: 25% of the shares underlying this option vested on January 27, 2023, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 10

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 130,481 shares

Expires 2032-01-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F5 · derivative.exercise_date: 25% of the shares underlying this option vested on January 27, 2023, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and subject to the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 9

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,278

Underlying: Common Stock · 4,278 shares

Expires 2034-06-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F4 · derivative.exercise_date: 25% of the shares underlying this option vest on June 21, 2025, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · derivative · entry 8

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 4,278 shares

Expires 2034-06-26

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F4 · derivative.exercise_date: 25% of the shares underlying this option vest on June 21, 2025, and the remaining shares vest in equal monthly installments thereafter over the following 36 months, subject to acceleration and the Reporting Person's continuous service to the Issuer on each such vesting date.

SEC source: 0001415889-24-018591 · form4-07012024_080730.xml · nonDerivative · entry 6

Bradley Mark Christopher · CIK 0002023657 · Chief Development Officer

10b5-1 filing: No plan indicated

Ownership: Indirect · By GRAT

Disclosed balance after: 20,026

F1 · kind: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F1 · price: Pursuant to a reclassification exempt under Rule 16b-7 and Rule 16b-3, each share of Class A Common Stock was reclassified into one share of voting Common Stock.

F3 · ownership.nature: Shares are owned directly by MB 2023 GRAT, for which Reporting Person serves as a trustee.