Form 4: Westlake BioPartners Increases Kyverna Stake

Westlake BioPartners, a 10% owner and director, acquired 133,333 shares of Kyverna Therapeutics common stock at $7.50 per share, increasing its indirect beneficial ownership.

Summary

• Westlake BioPartners Opportunity Fund I, L.P., a 10% owner and director of Kyverna Therapeutics, Inc. (KYTX), acquired additional common stock.
• On December 18, 2025, 133,333 shares of common stock were purchased at a price of $7.50 per share.
• This transaction was made pursuant to a Rule 10b5-1(c) pre-arranged plan.
• Following this acquisition, Westlake BioPartners Opportunity Fund I, L.P. indirectly beneficially owns 869,317 shares.
• Westlake BioPartners Fund I, L.P. indirectly beneficially owns an additional 3,787,940 shares.
• The total indirect beneficial ownership by the Westlake BioPartners entities is 4,657,257 shares.
• Sean Harper is no longer a managing director of Westlake Opportunity GP I and Westlake GP I, and therefore is not a reporting person on this Form 4.

Sentiment

Score: 7

Explanation: The insider purchase by a significant investor and director, Westlake BioPartners, indicates a positive sentiment and confidence in the company's valuation and future prospects. The transaction being part of a 10b5-1 plan suggests a pre-planned investment strategy.

Positives

• A significant insider purchase of 133,333 shares by a 10% owner and director, Westlake BioPartners, indicates confidence in Kyverna Therapeutics' future prospects.
• The transaction was executed at $7.50 per share, providing a clear valuation point for this insider acquisition.

Negatives

• No specific negative points are detailed in this Form 4 filing.

Risks

• No specific risks are mentioned in this Form 4 filing.

Future Outlook

The filing does not provide specific forward-looking statements or guidance beyond the reported transaction.

Management Comments

• Beth Seidenberg disclaims beneficial ownership of the shares held by Westlake Opportunity and Westlake I except to the extent of such person's pecuniary interest therein, if any.
• Sean Harper is no longer a managing director of Westlake Opportunity GP I and Westlake GP I, and accordingly, is not a Reporting Person on this Form 4.

Industry Context

This insider purchase by a significant institutional investor in Kyverna Therapeutics, a biotechnology company, suggests continued belief in the company's long-term potential within the competitive biotech sector. Such transactions can be viewed positively by the market, especially in a sector often characterized by high R&D costs and regulatory hurdles.

Comparison to Industry Standards

• Not applicable as this Form 4 details an insider transaction rather than operational or financial performance metrics that would typically be compared to industry benchmarks or specific comparable companies/projects.

Management Changes

Corporate Governance

Legal Proceedings

• No legal proceedings or regulatory matters are mentioned in this Form 4 filing.

Related Party Transactions

• The acquisition of 133,333 shares of common stock by Westlake BioPartners Opportunity Fund I, L.P., a 10% owner and director of Kyverna Therapeutics, Inc., constitutes a related party transaction.

Stakeholder Impact

• Shareholders: The insider purchase by a significant investor could instill greater confidence among existing and potential shareholders, potentially leading to positive market perception.
• Management: The continued investment by a director and major shareholder may reinforce alignment between management and key investors.

Next Steps

• The filing does not explicitly mention any future actions, events, or milestones.

Key Dates

Recommendation

The significant insider purchase by Westlake BioPartners, a 10% owner and director, at a price of $7.50 per share, signals strong confidence in Kyverna Therapeutics' valuation and future outlook. Such an acquisition, especially when part of a pre-arranged 10b5-1 plan, suggests a deliberate investment strategy and positive long-term conviction from a sophisticated investor. This insider buying activity typically serves as a bullish indicator for the stock.

Keywords

Kyverna Therapeutics, KYTX, Westlake BioPartners, Insider Buying, Form 4, Stock Purchase, Beneficial Ownership, 10b5-1 plan, Biotechnology, Investment Fund