Sec Form 4 Filing - Redmile Group, LLC @ IGM Biosciences, Inc. - 2025-08-14

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

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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Redmile Group, LLC 2. Issuer Name and Ticker or Trading Symbol IGM Biosciences, Inc. [ IGMS] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) ONE LETTERMAN DRIVE, BUILDING D, SUITE D3-300 3. Date of Earliest Transaction (MM/DD/YY) 08/14/2025 (Street) SAN FRANCISCO, CA94129 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 08/14/2025 D 2,964,843 D 0 I See Footnotes ( 5 ) ( 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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 7. Title and Amount of Underlying Securities (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 of Derivative Security: 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 Non-Voting Common Stock ( 3 ) 08/14/2025 D 7,199,325 ( 1 ) ( 3 ) ( 3 ) Common Stock 7,199,325 ( 1 ) 0 I See Footnotes ( 5 ) ( 6 ) Pre-Funded Warrants to Purchase Common Stock $ 0.01 08/14/2025 D 667,666 ( 2 ) 12/11/2020 ( 4 ) Common Stock 667,666 ( 2 ) 0 I See Footnotes ( 5 ) ( 6 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Redmile Group, LLC ONE LETTERMAN DRIVE, BUILDING D SUITE D3-300 SAN FRANCISCO, CA94129 X X Green Jeremy C/O REDMILE GROUP, LLC (NY OFFICE) 45 W. 27TH STREET, FLOOR 11 NEW YORK, NY10001 X Signatures By: /s/ Jeremy Green, Managing Member of Redmile Group, LLC 08/15/2025 Signature of Reporting Person Date /s/ Jeremy Green 08/15/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )On August 14, 2025, pursuant to the terms of the Agreement and Plan of Merger (the "Merger Agreement"), dated as of July 1, 2025, among the Issuer, Concentra Biosciences, LLC, a Delaware limited liability company ("Parent"), and Concentra Merger Sub V, Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"), Merger Sub completed a tender offer to purchase all outstanding shares of the Issuer's Common Stock and Non-Voting Common Stock ("Issuer Shares") in exchange for (a) a price per share of $1.247 in cash (the "Offer Price"), subject to applicable tax withholding and without interest, plus (b) one contingent value right ("CVR") per share subject to the terms and conditions of a Contingent Value Rights Agreement ("CVR Agreement"). The tender offer expired one minute following 11:59 p.m., Eastern Time, on August 13, 2025 (the "Offer Closing"). ( 2 )On August 14, 2025, the Issuer completed its merger transaction with and into Merger Sub pursuant to the terms of the Merger Agreement, with the Issuer surviving as a wholly owned subsidiary of Parent (the "Merger"). At the effective date and time of the Merger (the "Merger Closing"), each outstanding and unexercised pre-funded warrant to purchase shares of the Issuer's Common Stock (each, a "Pre-Funded Warrant") was cancelled and the holder received the right to a cash amount based on the Offer Price, subject to applicable tax withholding and without interest, less the exercise price per share underlying the Pre-Funded Warrant, plus one CVR per underlying share subject to the terms and conditions of a CVR Agreement. ( 3 )The Non-Voting Common Stock was convertible into shares of the Issuer's common stock at any time, in accordance with the terms of the Issuer's Amended and Restated Certificate of Incorporation at any time and from time to time at the holder's election on a 1-for-1 basis. The Non-Voting Common Stock had no expiration date. ( 4 )The Pre-Funded Warrants to purchase common stock of the Issuer have no expiration date. ( 5 )The Common Stock, Non-Voting Common Stock, and Pre-Funded Warrants of the Issuer reported herein were directly owned by certain private investment vehicles managed by Redmile (each, a "Redmile Fund"), and may have been deemed beneficially owned by Redmile as investment manager of the Redmile Funds. ( 6 )The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile (collectively with Redmile, the "Reporting Persons"). The Reporting Persons disclaim beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any, and this Form 4 shall not be deemed an admission that either Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

Remarks: Michael Lee, a managing director of Redmile, resigned as a member of the board of directors of the Issuer immediately prior to the Merger Closing.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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