PFM Health Sciences and related entities report owning 401,110 shares (0.9%) of Werewolf Therapeutics, Inc. (HOWL). The filing states that PFM Health Sciences, LP, PFM Health Sciences GP, LLC, Partner Asset Management, LLC and Brian D. Grossman may each be deemed to beneficially own 401,110 shares, representing 0.9% of the 44,873,646 shares outstanding used for the calculation. All reporting persons indicate no sole voting or dispositive power and 401,110 shares of shared voting and dispositive power. The statement clarifies the relationships among the entities and includes a certification that the securities were not acquired to influence control.
Positive
None.
Negative
None.
Insights
TL;DR: Routine Schedule 13G filing disclosing a sub-5% passive stake; no control intent indicated.
The filing shows a passive position of 401,110 shares (0.9%) held through affiliated entities and HCM. The report emphasizes shared voting/dispositive power and expressly disclaims an intent to influence control. For investors, this is a transparency disclosure rather than an active governance signal. The position size is below 5%, so it does not trigger Schedule 13D requirements or suggest a takeover attempt. Metrics are straightforward and based on 44,873,646 shares outstanding used for the percentage calculation.
The filing details the chain of advisory and partnership relationships (PFM, PAM, PFM-GP, and Grossman) and shows identical beneficial ownership figures across reporting persons, which is common for investment manager structures. The certification and explicit statements about voting/dispositive powers indicate the holders view the stake as non-control and compliant with Schedule 13G standards. No group formation, dissolution, or contested actions are disclosed.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 4)
Werewolf Therapeutics, Inc.
(Name of Issuer)
Common stock, par value $0.0001 per share (the "Shares")
(Title of Class of Securities)
95075A107
(CUSIP Number)
06/30/2025
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
SCHEDULE 13G
CUSIP No.
95075A107
1
Names of Reporting Persons
PFM Health Sciences, LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
401,110.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
401,110.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
401,110.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.9 %
12
Type of Reporting Person (See Instructions)
IA, PN
Comment for Type of Reporting Person: The percentages reported in this Schedule 13G are based upon 44,873,646 Shares outstanding as of May 2, 2025 (according to the issuer's Form 10-Q as filed with the Securities and Exchange Commission on May 8, 2025).
SCHEDULE 13G
CUSIP No.
95075A107
1
Names of Reporting Persons
PFM Health Sciences GP, LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
401,110.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
401,110.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
401,110.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.9 %
12
Type of Reporting Person (See Instructions)
HC, OO
SCHEDULE 13G
CUSIP No.
95075A107
1
Names of Reporting Persons
Partner Asset Management, LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
401,110.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
401,110.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
401,110.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.9 %
12
Type of Reporting Person (See Instructions)
HC, OO
SCHEDULE 13G
CUSIP No.
95075A107
1
Names of Reporting Persons
Brian D. Grossman
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
401,110.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
401,110.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
401,110.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.9 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Werewolf Therapeutics, Inc.
(b)
Address of issuer's principal executive offices:
200 Talcott Avenue 2nd Floor Watertown, MA, 02472
Item 2.
(a)
Name of person filing:
This Schedule 13G is being jointly filed by PFM Health Sciences, LP ("PFM"), PFM Health Sciences GP, LLC ("PFM-GP"), Partner Asset Management, LLC ("PAM"), and Brian D. Grossman ("Grossman" and, collectively with PFM, PFM-GP, and PAM, the "Reporting Persons") with respect to shares of common stock of the above-named issuer owned by PFM Healthcare Master Fund, L.P., a Cayman Islands limited partnership ("HCM").
PFM is the investment advisor for the HCM. PAM is the general partner of the HCM. PFM-GP is the general partner of PFM and the manager of PAM. Grossman is the sole member of PFM-GP.
The filing of this statement shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any securities covered by the statement other than the securities actually owned by such person (if any).
(b)
Address or principal business office or, if none, residence:
The address of the principal business office of each of the Reporting Persons is c/o PFM Health Sciences, LP, 475 Sansome Street, Suite 1720, San Francisco, California 94111
(c)
Citizenship:
PFM is organized as a limited partnership under the laws of the State of Delaware. Each of PFM-GP and PAM is organized as a limited liability company under the laws of the State of Delaware. Grossman is a U.S. citizen.
(d)
Title of class of securities:
Common stock, par value $0.0001 per share (the "Shares")
(e)
CUSIP No.:
95075A107
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
1. Each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC may be deemed to beneficially own 401,110 Shares.
2. Mr. Grossman may be deemed to beneficially own 401,110 Shares.
(b)
Percent of class:
1. The number of Shares that each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC may be deemed to beneficially own constitutes 0.9% of the Shares outstanding.
2. The number of Shares that Mr. Grossman may be deemed to beneficially own constitutes 0.9% of the Shares outstanding.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
1. Each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC: 0
2. Mr. Grossman: 0
(ii) Shared power to vote or to direct the vote:
1. Each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC: 401,110
2. Mr. Grossman: 401,110
(iii) Sole power to dispose or to direct the disposition of:
1. Each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC: 0
2. Mr. Grossman: 0
(iv) Shared power to dispose or to direct the disposition of:
1. Each of PFM Health Sciences, LP, PFM Health Sciences GP, LLC and Partner Asset Management, LLC: 401,110
2. Mr. Grossman: 401,110
Item 5.
Ownership of 5 Percent or Less of a Class.
Ownership of 5 percent or less of a class
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
PFM Health Sciences, LP
Signature:
/s/ Darren Mooney
Name/Title:
Darren Mooney, Authorized Signatory
Date:
08/14/2025
PFM Health Sciences GP, LLC
Signature:
/s/ Darren Mooney
Name/Title:
Darren Mooney, Authorized Signatory
Date:
08/14/2025
Partner Asset Management, LLC
Signature:
/s/ Darren Mooney
Name/Title:
Darren Mooney, Authorized Signatory
Date:
08/14/2025
Brian D. Grossman
Signature:
/s/ Darren Mooney
Name/Title:
Darren Mooney, attorney-in-fact*
Date:
08/14/2025
Comments accompanying signature: * Darren Mooney is signing on behalf of Brian Grossman as attorney-in-fact pursuant to a power of attorney dated February 1, 2024, and incorporated by reference herein. The power of attorney was filed as an attachment to a filing by certain of the Reporting Persons on Schedule 13G/A for Praxis Precision Medicines, Inc. on February 14, 2024.
What stake does PFM Health Sciences report in Werewolf Therapeutics (HOWL)?
The reporting persons each disclose beneficial ownership of 401,110 shares, representing 0.9% of the class based on 44,873,646 shares outstanding.
Does the filing signal an attempt to change control of HOWL?
No. The filing includes a certification stating the securities were not acquired and are not held to change or influence control, consistent with a Schedule 13G passive filing.
Who are the reporting persons named in the Schedule 13G/A for HOWL?
The filing is jointly made by PFM Health Sciences, LP; PFM Health Sciences GP, LLC; Partner Asset Management, LLC; and Brian D. Grossman.
What voting and dispositive powers are reported for the shares?
Each reporting person reports 0 shares with sole voting or dispositive power and 401,110 shares with shared voting and shared dispositive power.
What date and documents support the outstanding share count used for the percentage?
The percentage is based on 44,873,646 shares outstanding as of May 2, 2025, according to the issuer filing referenced in the Schedule 13G/A.