Alumis insider James B. Tananbaum adds 507k ALMS shares

Rhea-AI Filing Summary

Alumis Inc. (ALMS) director and 10% owner James B. Tananbaum reported multiple open-market purchases of the company’s common stock. On November 17–19, 2025, entities he is associated with bought a total of 507,874 shares at prices ranging from $5.59 to $6.56 per share, increasing his indirect beneficial ownership in Alumis. The shares are held across several Foresite-affiliated investment vehicles, including Foresite Capital Opportunity Fund V, Foresite Capital Fund VI, Foresite Capital Fund V, Labs Co-Invest V, Foresite Labs Fund I and Foresite Labs Affiliates 2021. Tananbaum reports potential voting and dispositive power through these entities but disclaims group status and beneficial ownership beyond his pecuniary interest.

Insider Trade Summary

Net Buyer: 507,874 shares ($3,094,725)

Net Buy 9 txns

Insider Tananbaum James B.

Role Director, 10% Owner

Bought 507,874 shs ($3.09M)

Type	Security	Shares	Price	Value
Purchase	Common Stock	190,500	$6.56	$1.25M
Purchase	Common Stock	117,374	$6.19	$727K
Purchase	Common Stock	50,000	$5.60	$280K
Purchase	Common Stock	150,000	$5.59	$839K
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 2,542,003 shares (Indirect, See Footnote)

Footnotes (1)

1. 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. 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. 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. 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. 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. 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.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Tananbaum James B.

(Last) (First) (Middle)

900 LARKSPUR LANDING CIRCLE

SUITE 150

(Street)

LARKSPUR CA 94939

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ALUMIS INC. [ ALMS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
11/17/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/17/2025		P		50,000	A	$5.6	2,084,129	I	See Footnote(1)
Common Stock	11/17/2025		P		150,000	A	$5.59	2,234,129	I	See Footnote(1)
Common Stock	11/18/2025		P		117,374	A	$6.19	2,351,503	I	See Footnote(1)
Common Stock	11/19/2025		P		190,500	A	$6.56	2,542,003	I	See Footnote(1)
Common Stock								4,247,670	I	See Footnote(2)
Common Stock								5,584,889	I	See Footnote(3)
Common Stock								194,459	I	See Footnote(4)
Common Stock								1,960,337	I	See Footnote(5)
Common Stock								1,176,470	I	See Footnote(6)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. 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.

2. 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.

3. 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.

4. 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.

5. 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.

6. 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.

Remarks:

This Form 4 is one of three Form 4s filed on the date hereof in respect of these transactions. The Reporting Persons for the other Form 4s are Fund V, Opportunity Fund V, Labs Co-Invest, Fund VI, Labs Fund I, Labs Affiliates, FCM V, FCOM V, FCM VI, FLM I and Labs.

	/s/ James B. Tananbaum	11/19/2025
	** Signature of Reporting Person	Date
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