ALUMIS INC. — Director's Dealing 2025

Nov 20, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ALUMIS INC. (ALMS)
CIK: 0001847367
Period of Report: 2025-11-17

Reporting Person: Tananbaum James B. (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-11-17	Common Stock	P	50000	$5.60	Acquired	2084129	Indirect
2025-11-17	Common Stock	P	150000	$5.59	Acquired	2234129	Indirect
2025-11-18	Common Stock	P	117374	$6.19	Acquired	2351503	Indirect
2025-11-19	Common Stock	P	190500	$6.56	Acquired	2542003	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	4247670	Indirect
Common Stock	5584889	Indirect
Common Stock	194459	Indirect
Common Stock	1960337	Indirect
Common Stock	1176470	Indirect

Footnotes

F1: The shares are held of record by Foresite Capital Opportunity Fund V, L.P. ("Opportunity Fund V"). Foresite Capital Opportunity Management V, LLC ("FCOM V") is the general partner of Opportunity Fund V and may be deemed to have sole voting and dispositive power over such shares. James B. Tananbaum ("Tananbaum"), the managing member of FCOM V, 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, other than Opportunity Fund V, disclaims beneficial ownership of the shares held by Opportunity Fund V, except to the extent of such person's pecuniary interest in such securities.

F2: 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. 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 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.

F3: The shares are held of record by Foresite Capital Fund V, L.P. ("Fund V"). Foresite Capital Management V, LLC ("FCM V") is the general partner of Fund V and may be deemed to have sole voting and dispositive power over such shares. Tananbaum, the managing member of FCM V, 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 Exchange Act, and disclaims beneficial ownership of the shares held by Fund V, except to the extent of such person's pecuniary interest in such securities.

F4: The shares are held of record by Labs Co-Invest V, LLC ("Labs Co-Invest"). FCM V is the managing member of Labs Co-Invest and may be deemed to have sole voting and dispositive power over such shares. Tananbaum, the managing member of FCM V, 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 Exchange Act, and disclaims beneficial ownership of the shares held by Labs Co-Invest, except to the extent of such person's pecuniary interest in such securities.

F5: The shares are held of record by Foresite Labs Fund I, L.P. ("Labs Fund I"). Foresite Labs Management I, LLC ("FLM I") is the general partner of Labs Fund I and may be deemed to have sole voting and dispositive power over such shares. Tananbaum, the managing member of FLM I, 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 Exchange Act, and disclaims beneficial ownership of the shares held by Labs Fund I, except to the extent of such person's pecuniary interest in such securities.

F6: The shares are held of record by Foresite Labs Affiliates 2021, LLC ("Labs Affiliates"). Foresite Labs, LLC ("Labs") is the managing member of Labs Affiliates and may be deemed to have sole voting and dispositive power over such shares. Tananbaum, a manager of Labs, may be deemed to share voting and dispositive power over such shares. Tananbaum disclaims the existence of a "group", as defined in Rule 13d-5 of the Exchange Act, and disclaims beneficial ownership of the shares held by Labs Affiliates, except to the extent of such person's pecuniary interest in such securities.