Form 4: Werewolf Therapeutics 10% Owner Sells Shares

A 10% owner and director of Werewolf Therapeutics, Ansbert Gadicke and related entities, reported the sale of over 160,000 common shares in mid-November 2025 under a pre-established trading plan.

Summary

• Ansbert Gadicke, a director and 10% owner of Werewolf Therapeutics, Inc. (HOWL), along with several affiliated entities (MPM Oncology Innovations Fund LP, UBS Oncology Impact Fund L.P., Oncology Impact Fund (Cayman) Management L.P., MPM BioImpact LLC, MPM Oncology Innovations Fund GP LLC, and MPM Asset Management LLC), reported sales of common stock.
• A total of 160,103 shares were sold across three transactions between November 18, 2025, and November 20, 2025.
• The sales were executed pursuant to a Rule 10b5-1 trading plan established on September 24, 2025.
• On November 18, 2025, 52,627 shares were sold at a weighted average price of $0.93, with prices ranging from $0.8902 to $0.9601.
• On November 19, 2025, 66,324 shares were sold at a weighted average price of $0.94, with prices ranging from $0.901 to $0.9806.
• On November 20, 2025, 41,152 shares were sold at a weighted average price of $0.89, with prices ranging from $0.8506 to $0.9556.
• Following these transactions, the reporting persons beneficially own 5,321,436 shares indirectly through various MPM entities.

Sentiment

Score: 3

Explanation: The sentiment is negative due to significant insider selling by a director and 10% owner, even though it was pre-planned. The declining weighted average sale price over the transaction period further contributes to a cautious outlook.

Positives

• The sales were conducted under a pre-established Rule 10b5-1 trading plan, indicating they were not opportunistic and were planned in advance, which can mitigate the negative signal of insider selling.

Negatives

• A director and 10% owner, along with affiliated entities, sold a significant number of common shares (160,103 shares).
• The sales occurred at prices ranging from $0.8506 to $0.9806, which are relatively low, especially the $0.89 weighted average on November 20, 2025.
• The continued reduction in beneficial ownership by a significant insider group could be interpreted as a lack of confidence in the company's near-term stock performance.

Risks

• Insider selling, even under a 10b5-1 plan, can sometimes be perceived by the market as a negative signal regarding the company's future prospects or valuation.
• The declining weighted average price of sales over the three days ($0.93, $0.94, $0.89) could suggest a downward trend in the stock price during the transaction period.

Future Outlook

NA

Industry Context

This Form 4 filing is specific to insider transactions at Werewolf Therapeutics and does not provide broader industry context or trends. However, insider selling in the biotechnology sector can sometimes be viewed with caution, especially for companies in early development stages where investor confidence is crucial.

Related Party Transactions

• Ansbert Gadicke, a director and 10% owner, is associated with multiple entities (MPM Oncology Innovations Fund LP, UBS Oncology Impact Fund L.P., Oncology Impact Fund (Cayman) Management L.P., MPM BioImpact LLC, MPM Oncology Innovations Fund GP LLC, MPM Asset Management LLC) that collectively sold shares. These entities are considered related parties due to common control and influence by Mr. Gadicke.

Stakeholder Impact

• Shareholders: Existing shareholders may view the insider selling as a negative signal, potentially leading to downward pressure on the stock price.
• Employees: No direct impact mentioned, but a declining stock price could affect morale or equity compensation value.
• Customers/Suppliers/Creditors: No direct impact mentioned.

Key Dates

Recommendation

The significant selling by a director and 10% owner, Ansbert Gadicke, and his affiliated entities, signals a lack of conviction in the company's near-term prospects. While executed under a 10b5-1 plan, the sheer volume of shares sold (over 160,000) and the declining weighted average sale prices over the three days suggest that these insiders are reducing their exposure. This insider activity, particularly from a substantial owner, often precedes periods of underperformance or reflects a belief that the stock is fully valued or may face headwinds. Therefore, a 'sell' recommendation is warranted for investors to consider reducing their own exposure.

Keywords

Werewolf Therapeutics, HOWL, SEC Form 4, Insider Selling, Ansbert Gadicke, MPM BioImpact, 10b5-1 Plan, Biotechnology, Stock Sales, Beneficial Ownership