Form 4: ALUMIS Director Boosts Stake with $7.0M Stock Purchase

James B. Tananbaum, a Director and 10% owner of ALUMIS INC., acquired 411,764 shares of common stock for $17 per share, totaling approximately $7.0 million, on January 8, 2026.

Summary

• James B. Tananbaum, a Director and 10% owner of ALUMIS INC. (ALMS), purchased common stock.
• The transactions occurred on January 8, 2026.
• A total of 411,764 shares of common stock were acquired at a price of $17 per share.
• The total value of the acquired shares is approximately $7,000,000.
• The shares were acquired indirectly through various entities including Foresite Capital Fund V, L.P., Foresite Capital Opportunity Fund V, L.P., Foresite Capital Fund VI, L.P., Labs Co-Invest V, LLC, Foresite Labs Fund I, L.P., and Foresite Labs Affiliates 2021, LLC.
• Tananbaum disclaims beneficial ownership of the shares held by these entities, except to the extent of his pecuniary interest in such securities.

Sentiment

Score: 7

Explanation: The significant purchase of shares by a director and 10% owner suggests strong insider confidence in the company's valuation and future prospects.

Positives

• A Director and 10% owner, James B. Tananbaum, purchased a significant number of shares (411,764 shares) at $17 per share, indicating strong insider confidence.
• The total investment of approximately $7.0 million by a key insider suggests a positive outlook on the company's future valuation.

Stakeholder Impact

• Shareholders may interpret the significant insider purchase as a strong signal of confidence from a key director and major investor, potentially leading to increased investor interest.

Key Dates

Recommendation

The significant purchase of shares by a director and 10% owner, James B. Tananbaum, signals strong insider confidence in ALUMIS INC. This action, while positive, should be considered as one data point within a broader investment analysis. It reinforces a 'hold' position for existing investors and could be a positive indicator for those considering an investment, but a 'buy' recommendation would require further fundamental analysis beyond this transaction.

Keywords

ALUMIS INC., ALMS, Insider Trading, Form 4, Stock Purchase, Director, 10% Owner, James B. Tananbaum, Foresite Capital