Washington, D.C. 20549


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 Number: 3235-0104
Estimated average burden
hours per response: 0.5
1. Name and Address of Reporting Person*
Haldor Topsoe Holding A/S

(Last) (First) (Middle)


(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
3. Issuer Name and Ticker or Trading Symbol
IGM Biosciences, Inc. [ IGMS ]
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director X 10% Owner
Officer (give title below) Other (specify below)
5. 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 Beneficially Owned
1. Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5)
Table II - Derivative Securities Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4) 2. Date Exercisable and Expiration Date (Month/Day/Year) 3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 6. Nature of Indirect Beneficial Ownership (Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Series B Preferred Stock (1) (1) Common Stock 9,039,453 0.00 D(2)
Series C Preferred Stock (3) (3) Non-Voting Common Stock 2,269,838 0.00 D(2)
Explanation of Responses:
1. The Series B Preferred Stock will automatically convert into shares of Common Stock on a 1-for-1 basis immediately prior to the closing of the Issuer's initial public offering. The Series B Preferred Stock does not have an expiration date.
2. All shares are held directly by Haldor Topsoe Holdings A/S (HTH). Mr. Jakob Haldor Topsoe, Ms. Christina Teng Topsoe, Mr. Martin Topsoe and Mr. Emil Oigaard, members of the board of directors of HTH, may be deemed to share voting and investment power with respect to the shares reported herein and disclaim beneficial ownership of such shares, except to the extent of his or her pecuniary interest therein, if any. Mr. Jakob Haldor Topsoe and Ms. Christina Teng Topsoe are members of the Issuer's board of directors.
3. The Series C Preferred Stock will automatically convert into shares of Non-Voting Common Stock on a 1-for-1 basis, pursuant to an election made by the Reporting Person, immediately prior to the closing of the Issuer's initial public offering, and has no expiration date. Each share of Non-Voting Common Stock is convertible at any time at the option of the Reporting Person into one share of Common Stock (subject to a 4.99% beneficial ownership limitation that may be increased or decreased by the Reporting Person) and has no expiration date.
/s/ Misbah Tahir, by power of attorney 09/17/2019
** Signature of Reporting Person Date
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 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

The undersigned, as a Section 16 reporting person of IGM Biosciences, Inc. (the
"Company"), hereby constitutes and appoints Fred Schwarzer and Misbah Tahir, and
each of them, as the undersigned's true and lawful attorney-in-fact to:

1.	complete and execute Forms 3, 4 and 5 and other forms and all amendments
thereto as such attorney-in fact shall in his discretion determine to be
required or advisable pursuant to Section 16 of the Securities Exchange Act of
1934 (as amended) and the rules and regulations promulgated thereunder, or any
successor laws and regulations, as a consequence of the undersigned's ownership,
acquisition or disposition of securities of the Company; and

2.	do all acts necessary in order to file such forms with the Securities and
Exchange Commission, any securities exchange or national association, the
Company and such other person or agency as the attorneys-in-fact shall deem

The undersigned hereby ratifies and confirms all that said attorneys-in-fact and
agents shall do or cause to be done by virtue hereof. The undersigned
acknowledges that the foregoing attorneys-in-fact, in serving in such capacity
at the request of the undersigned, are not assuming, nor is the Company
assuming, any of the undersigned's responsibilities to comply with Section 16 of
the Securities Exchange Act of 1934 (as amended). This Power of Attorney shall
remain in full force and effect until the undersigned is no longer required to
file Forms 3, 4 and 5 with respect to the undersigned's holdings of and
transactions in securities issued by the Company, unless earlier revoked by the
undersigned in a signed writing delivered to the Company and the foregoing

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 12th day of  September, 2019.


By: /s Henrik Gaarn Bak
Name: Henrik Gaarn Bak
Title: Managing Director