Form
SCHEDULE 13D/A
Active or control-oriented beneficial ownership filing.
MPM BioVentures 2014, L.P. - 22 Dec 2025 SCHEDULE 13D/A Report for WEREWOLF THERAPEUTICS, INC. Common Stock (HOWL)
- Filing manager
- MPM BioVentures 2014, L.P.
- Reporting owner
- ANSBERT GADICKE
- Beneficially owned shares
- 3,977,612 shares
- Large-stake signal
-
Ownership
8.2%Beneficial ownership of this reported class.
Shares
3,977,612 sharesShares beneficially owned as disclosed.
Event date
22 Dec 2025Date tied to the ownership event or amendment.
Accepted by SEC
29 Dec 2025EDGAR acceptance date.
How to read this large-stake filing
- Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
- Compare this filing with the holder history and issuer page before treating the percentage as a current position.
- Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
- Class ownership
- 8.2%
- Symbol
- HOWL
- Shares outstanding
- 48,507,463 shares
- SEC form
- SCHEDULE 13D/A
- Accepted by SEC
- 29 Dec 2025, 18:59:21 UTC
- Event date
- 22 Dec 2025
- Prior SEC filing
- 03 Dec 2025
- Next SEC filing
- 16 Jan 2026
- Source filing
- View source filing
Ownership signal
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Subject security
Names, identifiers, and filing context for this profile.
2 source fields
Source evidence
Original filing metadata and source links for verification.
6 source fields
Key filing fact
MPM BioVentures 2014, L.P. disclosed 8.2% ownership in WEREWOLF THERAPEUTICS, INC. Common Stock (HOWL) on 22 Dec 2025.
Key facts
- MPM BioVentures 2014, L.P. filed SCHEDULE 13D/A for WEREWOLF THERAPEUTICS, INC. Common Stock (HOWL).
- Disclosed ownership: 8.2%.
- Date of event: 22 Dec 2025.
Change
- Previous schedule filing date: 03 Dec 2025.
- Current filing was accepted on 29 Dec 2025, 18:59.
Research use
- This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
- Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.
Evidence
Backed by Schedule 13D/13G
View source filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting persons
Disclosed reporting parties (14)
Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.
| Name | Ownership | Shares owned | Sole voting power | Shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| MPM BioVentures 2014, L.P. | 3.6% | 1,725,184 | 1,725,184 | 0 | /s/ Ansbert Gadicke | Managing Director of MPM BioVentures 2014 LLC, the Managing Member of MPM BioVentures 2014 GP LLC, the General Partner of MPM BioVentures 2014, L.P. | 0001609492 |
| MPM BioVentures 2014 (B), L.P. | 0.2% | 115,066 | 115,066 | 0 | /s/ Ansbert Gadicke | Managing Director of MPM BioVentures 2014 LLC, Managing Member of MPM BioVentures 2014 GP LLC, the General Partner of MPM BioVentures 2014 (B), L.P. | 0001609493 |
| MPM Asset Management Investors BV2014 LLC | 0.1% | 59,379 | 59,379 | 0 | /s/ Ansbert Gadicke | Managing Director of MPM BioVentures 2014 LLC, the manager of MPM Asset Management Investors BV2014 LLC | 0001609495 |
| UBS Oncology Impact Fund L.P. | 2.9% | 1,426,938 | 1,426,938 | 0 | /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. | 0001691428 |
| MPM BioVentures 2014 GP LLC | 3.8% | 1,840,250 | 0 | 1,840,250 | /s/ Ansbert Gadicke | Managing Director of MPM BioVentures 2014 LLC, the Managing Member of MPM BioVentures 2014 GP LLC | 0001765091 |
| MPM BioVentures 2014 LLC | 3.9% | 1,899,629 | 0 | 1,899,629 | /s/ Ansbert Gadicke | Managing Director | 0001765021 |
| Oncology Impact Fund (Cayman) Management L.P. | 2.9% | 1,426,938 | 0 | 1,426,938 | /s/ Ansbert Gadicke | Managing Partner of MPM BioImpact LLC, the General Partner of Oncology Impact Fund (Cayman) Management L.P. | 0001721036 |
| MPM BioImpact LLC | 2.9% | 1,426,938 | 0 | 1,426,938 | /s/ Ansbert Gadicke | Managing Partner | 0001687078 |
| ANSBERT GADICKE | 8.2% | 3,977,612 | 0 | 3,977,612 | /s/ Ansbert Gadicke | Ansbert Gadicke | 0001134655 |
| LUKE EVNIN | 5.3% | 2,550,674 | 0 | 2,550,674 | /s/ Luke Evnin | Luke Evnin | 0001134657 |
| Todd Foley | 3.9% | 1,899,629 | 0 | 1,899,629 | /s/ Todd Foley | Todd Foley | 0001473930 |
| MPM ASSET MANAGEMENT LLC | 0.6% | 273,218 | 273,218 | 0 | /s/ Ansbert Gadicke | Member | 0001263048 |
| MPM ONCOLOGY INNOVATIONS FUND LP | 0.8% | 377,827 | 377,827 | 0 | /s/ Ansbert Gadicke | Manager of MPM Oncology Innovations Fund GP LLC, the General Partner of MPM Oncology Innovations Fund, L.P. | 0001719960 |
| MPM Oncology Innovations Fund GP LLC | 0.8% | 377,827 | 0 | 377,827 | /s/ Ansbert Gadicke | Manager | 0001857903 |
CIK / CUSIP context first