Ansbert Gadicke - 26 Nov 2025 Form 4 Insider Report for Werewolf Therapeutics, Inc. (HOWL)

Reporting relationship: 10%+ Owner
Issuer ticker: HOWL
Reported as of: 26 Nov 2025
Net transaction value: -$136,855
SEC form: 4
Accepted by SEC: 01 Dec 2025, 18:11:02 UTC
Prior SEC filing: 25 Nov 2025
Next SEC filing: 04 Dec 2025
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 01 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: 01 Dec 2025, 18:11.

Change

Previous filing in this sequence was filed on 25 Nov 2025.
Current net transaction value: -$136,855.

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: 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: 01 Dec 2025

CIK 0001719960

MPM ONCOLOGY INNOVATIONS FUND LP

Relationship: 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: 01 Dec 2025

CIK 0001691428

UBS Oncology Impact Fund L.P.

Relationship: 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: 01 Dec 2025

CIK 0001721036

Oncology Impact Fund (Cayman) Management L.P.

Relationship: 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: 01 Dec 2025

CIK 0001687078

MPM BioImpact LLC

Relationship: 10%+ Owner
Address: C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON
Signature: /s/ Ansbert Gadicke
Signature date: 01 Dec 2025

CIK 0001857903

MPM Oncology Innovations Fund GP LLC

Relationship: 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: 01 Dec 2025

CIK 0001263048

MPM ASSET MANAGEMENT LLC

Relationship: 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: 01 Dec 2025

Reported non-derivative transactions

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

HOWL transaction

Common Stock

Sale

Transaction value: $59,518
Shares: -60,733
Change %: -1.2%
Price: $0.9800
Shares after: 5,065,037
Date: 26 Nov 2025
Ownership: See Footnotes
Footnotes: F1, F2, F3, F4, F5

HOWL transaction

Common Stock

Sale

Transaction value: $20,074
Shares: -20,277
Change %: -0.4%
Price: $0.9900
Shares after: 5,044,760
Date: 28 Nov 2025
Ownership: See Footnotes
Footnotes: F1, F4, F6, F7, F8

HOWL transaction

Common Stock

Sale

Transaction value: $57,262
Shares: -60,917
Change %: -1.2%
Price: $0.9400
Shares after: 4,983,843
Date: 01 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

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: 4,170 by MPM Asset Management LLC ("AM LLC"), 26,343 by MPM BioVentures 2014, L.P. ("BV 2014"), 1,757 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 907 by MPM Asset Management Investors BV2014 LLC ("AM BV2014"), 5,801 by MPM Oncology Innovations Fund, L.P. ("MPM OIF") and 21,755 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 $0.9328 to $1.01 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: 347,875 by AM LLC, 2,196,856 by BV 2014, 146,527 by BV 2014(B), 75,615 by AM BV2014, 481,700 by MPM OIF and 1,816,464 by UBS Oncology.

Footnote F6

The shares were sold as follows: 1,392 by AM LLC, 8,795 by BV 2014, 587 by BV 2014(B), 303 by AM BV2014, 1,937 by MPM OIF and 7,263 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 $0.9681 to $1.01 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: 346,483 by AM LLC, 2,188,061 by BV 2014, 145,940 by BV 2014(B), 75,312 by AM BV2014, 479,763 by MPM OIF and 1,809,201 by UBS Oncology.

Footnote F9

The shares were sold as follows: 4,182 by AM LLC, 26,423 by BV 2014, 1,762 by BV 2014(B), 910 by AM BV2014, 5,819 by MPM OIF and 21,821 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 $0.905 to $1.00 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: 342,301 by AM LLC, 2,161,638 by BV 2014, 144,178 by BV 2014(B), 74,402 by AM BV2014, 473,944 by MPM OIF and 1,787,380 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.