Ansbert Gadicke - 02 Dec 2025 Form 4 Insider Report for Werewolf Therapeutics, Inc. (HOWL)

Reporting relationship: Former 10% Owner
Issuer ticker: HOWL
Reported as of: 02 Dec 2025
Net transaction value: -$183,275
SEC form: 4
Accepted by SEC: 04 Dec 2025, 18:18:45 UTC
Prior SEC filing: 01 Dec 2025
Next SEC filing: 08 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Ansbert Gadicke, Manager of MPM Oncology Innovations Fund GP LLC, the GP of MPM Oncology Innovations Fund, L.P.

Key filing fact

Ansbert Gadicke filed Form 4 for Werewolf Therapeutics, Inc. (HOWL) on 04 Dec 2025.

Key facts

This page summarizes Ansbert Gadicke's Form 4 filing for Werewolf Therapeutics, Inc. (HOWL).
3 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 04 Dec 2025, 18:18.

Change

Previous filing in this sequence was filed on 01 Dec 2025.
Current net transaction value: -$183,275.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (7)

CIK 0001134655 Primary reporting owner

GADICKE ANSBERT

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, Manager of MPM Oncology Innovations Fund GP LLC, the GP of MPM Oncology Innovations Fund, L.P.
Signature date: 04 Dec 2025

CIK 0001719960

MPM ONCOLOGY INNOVATIONS FUND LP

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, Manager of MPM Oncology Innovations Fund GP LLC
Signature date: 04 Dec 2025

CIK 0001691428

UBS Oncology Impact Fund L.P.

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, Managing Partner of MPM BioImpact LLC
Signature date: 04 Dec 2025

CIK 0001721036

Oncology Impact Fund (Cayman) Management L.P.

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, member of MPM Asset Management LLC
Signature date: 04 Dec 2025

CIK 0001687078

MPM BioImpact LLC

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke
Signature date: 04 Dec 2025

CIK 0001857903

MPM Oncology Innovations Fund GP LLC

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, Managing Partner of MPM BioImpact LLC, the GP of Oncology Impact Fund (Cayman) Management L.P., the GP of UBS Oncology Impact Fund, L.P.
Signature date: 04 Dec 2025

CIK 0001263048

MPM ASSET MANAGEMENT LLC

Relationship: Former 10% Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke, Managing Partner of MPM BioImpact LLC, the GP of Oncology Impact Fund (Cayman) Management L.P.
Signature date: 04 Dec 2025

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

HOWL transaction

Common Stock

Sale

Transaction value: $52,757
Shares: -59,277
Change %: -1.2%
Price: $0.8900
Shares after: 4,924,566
Date: 02 Dec 2025
Ownership: See Footnotes
Footnotes: F1, F2, F3, F4, F5

HOWL transaction

Common Stock

Sale

Transaction value: $49,786
Shares: -57,225
Change %: -1.2%
Price: $0.8700
Shares after: 4,867,341
Date: 03 Dec 2025
Ownership: See Footnotes
Footnotes: F1, F4, F6, F7, F8

HOWL transaction

Common Stock

Sale

Transaction value: $80,733
Shares: -83,230
Change %: -1.7%
Price: $0.9700
Shares after: 4,784,111
Date: 04 Dec 2025
Ownership: See Footnotes
Footnotes: F1, F4, F9, F10, F11

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Section 16 status

Ansbert Gadicke is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may still apply in specific circumstances.

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 11 footnotes

Footnote F1

Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated September 24, 2025.

Footnote F2

The shares were sold as follows: 4,070 by MPM Asset Management LLC ("AM LLC"), 25,712 by MPM BioVentures 2014, L.P. ("BV 2014"), 1,715 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 884 by MPM Asset Management Investors BV2014 LLC ("AM BV2014"), 5,662 by MPM Oncology Innovations Fund, L.P. ("MPM OIF") and 21,234 by UBS Oncology Impact Fund L.P. ("UBS Oncology").

Footnote F3

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.852 to $0.9246 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F4

MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV LLC is the manager of AM BV2014. MPM Oncology Innovations Fund GP LLC ("MPM OIF GP") is the general partner of MPM OIF. MPM BioImpact LLC ("BioImpact") is the General Partner of Oncology Impact Fund (Cayman) Management L.P., the General Partner of UBS Oncology. Ansbert Gadicke is a member of AM LLC, a managing director of BV LLC, a manager of MPM OIF GP and the managing partner of BioImpact. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its pecuniary interest therein.

Footnote F5

The shares are held as follows: 338,231 by AM LLC, 2,135,926 by BV 2014, 142,463 by BV 2014(B), 73,518 by AM BV2014, 468,282 by MPM OIF and 1,766,146 by UBS Oncology.

Footnote F6

The shares were sold as follows: 3,929 by AM LLC, 24,821 by BV 2014, 1,656 by BV 2014(B), 854 by AM BV2014, 5,466 by MPM OIF and 20,499 by UBS Oncology.

Footnote F7

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.82 to $0.9256 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F8

The shares are held as follows: 334,302 by AM LLC, 2,111,105 by BV 2014, 140,807 by BV 2014(B), 72,664 by AM BV2014, 462,816 by MPM OIF and 1,745,647 by UBS Oncology.

Footnote F9

The shares were sold as follows: 5,714 by AM LLC, 36,101 by BV 2014, 2,408 by BV 2014(B), 1,243 by AM BV2014, 7,950 by MPM OIF and 29,814 by UBS Oncology.

Footnote F10

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.92 to $1.0208 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F11

The shares are held as follows: 328,588 by AM LLC, 2,075,004 by BV 2014, 138,399 by BV 2014(B), 71,421 by AM BV2014, 454,866 by MPM OIF and 1,715,833 by UBS Oncology.

SEC remarks

This filing is 1 of 2 identical filings due to limitations on number of Reporting Persons. See Form 4 filed by MPM BioVentures 2014, L.P.