Feeds › Ownership stakes (13D / 13G)
Ownership stakes (13D / 13G)
Investors who own more than 5% of a company, from activists (13D) to passive holders (13G).
About this data
- What it is
- An investor who owns more than 5% of a public company must say so. Investors who may try to influence the company, such as activists, file the longer Schedule 13D; passive holders file the shorter Schedule 13G.
- Who files it
- The investor, within days of crossing 5%, and again whenever the stake changes materially.
- How current
- We collect new filings throughout the day on SEC business days.
- Worth knowing
- 13G filings are far more common than 13D. A 13D usually means the investor intends to push for changes, so it tends to get more attention.
All of this comes from public filings.
Source and freshness · Information, not investment advice (disclaimer).
Filings per day, last 30 days
13D (activist) 13G (passive)
Latest ownership filings
Showing: ticker HOWL
| Filed | ScheduleBoth report a stake of more than 5%. A 13D is filed by investors who may try to influence the company, such as activists; a 13G by passive holders. | Company | Investor | Shares | % of shares | Filing |
|---|---|---|---|---|---|---|
| Sep 21, 2026 | SCHEDULE 13G | HOWL Werewolf Therapeutics, Inc. | Peter Moll | 2.54M | 5.2% | SCHEDULE 13G ↗ |
| Jul 2, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Healthcare Fund, L.P. | 1.85M | 3.8% | SCHEDULE 13D/A ↗ |
| Jul 2, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Rajeev Shah | 1.99M | 4.1% | SCHEDULE 13D/A ↗ |
| Jul 2, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Peter Kolchinsky | 1.99M | 4.1% | SCHEDULE 13D/A ↗ |
| Jul 2, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Management, L.P. | 1.99M | 4.1% | SCHEDULE 13D/A ↗ |
| Jun 26, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Healthcare Fund, L.P. | 2.72M | 5.6% | SCHEDULE 13D/A ↗ |
| Jun 26, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Rajeev Shah | 2.92M | 6.0% | SCHEDULE 13D/A ↗ |
| Jun 26, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Peter Kolchinsky | 2.92M | 6.0% | SCHEDULE 13D/A ↗ |
| Jun 26, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Management, L.P. | 2.92M | 6.0% | SCHEDULE 13D/A ↗ |
| Jun 22, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Healthcare Fund, L.P. | 3.41M | 7.0% | SCHEDULE 13D/A ↗ |
| Jun 22, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Rajeev Shah | 3.65M | 7.5% | SCHEDULE 13D/A ↗ |
| Jun 22, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Peter Kolchinsky | 3.65M | 7.5% | SCHEDULE 13D/A ↗ |
| Jun 22, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Management, L.P. | 3.65M | 7.5% | SCHEDULE 13D/A ↗ |
| Jun 15, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Healthcare Fund, L.P. | 4.80M | 9.9% | SCHEDULE 13D/A ↗ |
| Jun 15, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Rajeev Shah | 5.14M | 10.6% | SCHEDULE 13D/A ↗ |
| Jun 15, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Peter Kolchinsky | 5.14M | 10.6% | SCHEDULE 13D/A ↗ |
| Jun 15, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Management, L.P. | 5.14M | 10.6% | SCHEDULE 13D/A ↗ |
| May 14, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Healthcare Fund, L.P. | 5.71M | 11.7% | SCHEDULE 13D/A ↗ |
| May 14, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Rajeev Shah | 6.12M | 12.6% | SCHEDULE 13D/A ↗ |
| May 14, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Peter Kolchinsky | 6.12M | 12.6% | SCHEDULE 13D/A ↗ |
| May 14, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | RA Capital Management, L.P. | 6.12M | 12.6% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Oncology Innovations Fund GP LLC | 173,334 | 0.4% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Oncology Innovations Fund LP | 173,334 | 0.4% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Asset Management LLC | 125,480 | 0.3% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Todd Foley | 872,361 | 1.8% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Luke Evnin | 1.17M | 2.4% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Ansbert Gadicke | 1.83M | 3.8% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioImpact LLC | 655,471 | 1.3% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Oncology Impact Fund (Cayman) Management L.P. | 655,471 | 1.3% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 LLC | 872,361 | 1.8% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 GP LLC | 845,094 | 1.7% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | UBS Oncology Impact Fund L.P. | 655,471 | 1.3% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Asset Management Investors BV2014 LLC | 27,267 | 0.1% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 (B), L.P. | 52,840 | 0.1% | SCHEDULE 13D/A ↗ |
| May 12, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014, L.P. | 792,254 | 1.6% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Oncology Innovations Fund GP LLC | 247,526 | 0.5% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Oncology Innovations Fund LP | 247,526 | 0.5% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Asset Management LLC | 179,188 | 0.4% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Todd Foley | 1.25M | 2.6% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Luke Evnin | 1.67M | 3.4% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Ansbert Gadicke | 2.61M | 5.4% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioImpact LLC | 936,031 | 1.9% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | Oncology Impact Fund (Cayman) Management L.P. | 936,031 | 1.9% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 LLC | 1.25M | 2.6% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 GP LLC | 1.21M | 2.5% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | UBS Oncology Impact Fund L.P. | 936,031 | 1.9% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM Asset Management Investors BV2014 LLC | 38,939 | 0.1% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014 (B), L.P. | 75,458 | 0.2% | SCHEDULE 13D/A ↗ |
| May 5, 2026 | SCHEDULE 13D/A (amended) | HOWL Werewolf Therapeutics, Inc. | MPM BioVentures 2014, L.P. | 1.13M | 2.3% | SCHEDULE 13D/A ↗ |
| Feb 11, 2026 | SCHEDULE 13G/A (amended) | HOWL Werewolf Therapeutics, Inc. | Longwood Fund III, L.P. | 1.68M | 3.5% | SCHEDULE 13G/A ↗ |
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