Form 4: Foresite Labs Boosts ALUMIS Stake by $7 Million

Foresite Labs, a 10% owner and director, increased its indirect beneficial ownership in ALUMIS INC. by acquiring 411,764 shares of common stock at $17 per share.

Summary

• Foresite Labs, LLC and Foresite Labs Affiliates 2021, LLC, both identified as 10% owners and directors of ALUMIS INC. (ALMS), reported an increase in their indirect beneficial ownership.
• On January 8, 2026, Foresite Capital Fund V, L.P. (an entity associated with Foresite Labs, LLC) acquired 117,647 shares of ALUMIS INC. common stock at a price of $17.00 per share.
• On the same date, Foresite Capital Opportunity Fund V, L.P. (another entity associated with Foresite Labs, LLC) acquired 294,117 shares of ALUMIS INC. common stock at a price of $17.00 per share.
• The total number of shares acquired in these transactions is 411,764, amounting to a total value of approximately $7,000,000.
• Following these transactions, the reporting persons indirectly beneficially own a total of 16,189,804 shares of ALUMIS INC. common stock across various affiliated funds and entities.
• The beneficial ownership is distributed among Foresite Capital Fund V, L.P. (5,702,536 shares), Foresite Capital Opportunity Fund V, L.P. (2,908,332 shares), Foresite Capital Fund VI, L.P. (4,247,670 shares), Labs Co-Invest V, LLC (194,459 shares), Foresite Labs Fund I, L.P. (1,960,337 shares), and Foresite Labs Affiliates 2021, LLC (1,176,470 shares).

Sentiment

Score: 7

Explanation: The sentiment is positive due to significant insider buying by a 10% owner and director, indicating confidence in the company's value. However, it's a single transaction report, not a comprehensive financial update.

Positives

• Significant insider buying by a 10% owner and director can signal strong confidence in the company's future prospects and valuation.
• The acquisition of 411,764 shares at a fixed price of $17.00 per share represents a substantial investment by a key stakeholder.

Risks

• The reporting persons disclaim the existence of a 'group' as defined in Rule 13d-5 of the Exchange Act, which could impact interpretations of collective ownership and influence.
• Beneficial ownership is disclaimed by the reporting persons, except to the extent of their pecuniary interest in the securities, which may complicate the assessment of direct control or influence.

Future Outlook

This Form 4 filing reports past transactions and does not contain explicit forward-looking statements or guidance from ALUMIS INC. or the reporting persons regarding future performance or strategy.

Management Comments

• James B. Tananbaum, as the managing member of various entities (FCM V, FCOM V, FCM VI, FLM I) and a manager of Foresite Labs, LLC, may be deemed to have sole or shared voting and dispositive power over the beneficially owned shares.

Industry Context

This insider transaction reflects a specific investment decision by a significant shareholder and director in ALUMIS INC. It does not directly provide broader industry trends or competitive analysis, but such a move by a prominent investment firm like Foresite Labs could be interpreted as a positive signal for the biotechnology or healthcare sector in which ALUMIS INC. likely operates.

Stakeholder Impact

• Shareholders may view this significant insider purchase as a positive indicator of management and major investor confidence in the company's future prospects, potentially influencing investor sentiment and stock price.
• The increased stake by Foresite Labs reinforces its position as a key institutional investor, potentially strengthening its influence on corporate strategy and governance.

Key Dates

Recommendation

Insider buying by a significant shareholder and director often signals confidence in the company's future prospects. However, this single transaction, while positive, does not provide enough comprehensive information to warrant a 'strong buy' or 'sell' recommendation without further fundamental analysis of ALUMIS INC.'s overall financial health, operational performance, and market position. A 'hold' recommendation reflects cautious optimism based on the insider's conviction.

Keywords

ALUMIS INC, ALMS, Foresite Labs, Insider Transaction, Form 4, Beneficial Ownership, Stock Acquisition, Institutional Investment, Director Purchase