SCHEDULE: MPM Entities Reduce Werewolf Therapeutics Stake

MPM BioVentures and affiliated entities reported open market sales of Werewolf Therapeutics common stock, reducing their collective beneficial ownership.

Summary

• Amendment No. 1 to Schedule 13D was filed by MPM BioVentures and affiliated entities (Filing Persons) regarding Werewolf Therapeutics Inc. common stock.
• The filing reports open market sales of the Issuer's Common Stock by certain Filing Persons.
• Ansbert Gadicke's aggregate beneficial ownership is 6,147,610 shares, representing 13.4% of the class.
• Luke Evnin's aggregate beneficial ownership is 3,943,359 shares, representing 8.6% of the class.
• Todd Foley's aggregate beneficial ownership is 2,936,048 shares, representing 6.4% of the class.
• MPM BioVentures 2014 LLC's aggregate beneficial ownership is 2,936,048 shares, representing 6.4% of the class.
• MPM BioVentures 2014, L.P. beneficially owns 2,666,424 shares, or 5.8% of the class.
• UBS Oncology Impact Fund L.P. beneficially owns 2,204,251 shares, or 4.8% of the class.
• The percentage of shares beneficially owned is calculated based on 45,728,999 common shares outstanding as of August 8, 2025.

Sentiment

Score: 3

Explanation: The filing reports significant open market sales by major beneficial owners and affiliated entities, including venture capital funds and their managing directors. While not a direct commentary on company performance, such a reduction in stake by key investors is generally perceived negatively by the market as it may signal a lack of confidence or a strategic exit.

Negatives

• Filing Persons, including MPM BioVentures and UBS Oncology Impact Fund, conducted open market sales of Werewolf Therapeutics common stock.
• Sales occurred between October 27, 2025, and November 3, 2025, with average prices ranging from $1.28 to $1.72 per share.
• Significant individual sales include 207,799 shares by BV 2014 and 177,519 shares by UBS Oncology.
• The aggregate number of shares sold by the reporting persons in the sixty days preceding the filing date is 486,210.

Future Outlook

NA

Industry Context

This filing reflects a significant reduction in stake by key venture capital and oncology-focused investment funds, MPM BioVentures and UBS Oncology Impact Fund, in a biotechnology company. Such sales by early-stage investors can sometimes signal a shift in investment strategy or a re-evaluation of the company's near-term prospects within the competitive biotech landscape.

Stakeholder Impact

• Shareholders: May interpret the significant sales by major investors as a negative signal, potentially leading to downward pressure on the stock price.
• Company Management: Could face questions regarding the reasons behind the substantial reduction in holdings by key institutional investors.

Key Dates

Recommendation

The substantial open market sales by multiple MPM BioVentures and UBS Oncology Impact Fund entities, along with their managing directors, suggest a significant reduction in their investment in Werewolf Therapeutics. This action by sophisticated institutional investors and insiders often signals a lack of conviction in the company's future prospects or current valuation, making a 'sell' recommendation prudent for investors considering the implications of such insider activity.

Keywords

WEREWOLF THERAPEUTICS, WW, MPM BioVentures, UBS Oncology Impact Fund, Schedule 13D/A, beneficial ownership, insider sales, biotechnology, venture capital, investment funds