Form 4: ARCH Venture Funds Adjust Boundless Bio Holdings

ARCH Venture Funds report changes in beneficial ownership of Boundless Bio, Inc. common stock, including option exercises and share dispositions.

Summary

• ARCH Venture Fund IX, L.P. acquired 16,000 shares of common stock at $1.03 per share on July 1, 2026, through the exercise of a stock option.
• The same entity, ARCH Venture Fund IX, L.P., disposed of 16,000 shares of common stock at $2.49 per share on July 1, 2026.
• Various ARCH Venture entities collectively hold a significant number of Boundless Bio shares, with ownership structures detailed through general partners and managing directors.
• The stock option exercised was granted to Kristina Burow in connection with her board of directors service and vested over 11 months, with the final portion vesting on June 15, 2026.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral filing, as it reports routine transactions of a venture capital fund adjusting its holdings rather than indicating significant company performance changes.

Positives

• The exercise of a stock option indicates potential value realization for the option holder.
• The acquisition of shares at $1.03 suggests a favorable entry point for the fund.
• The disposition of shares at $2.49 indicates a profitable transaction for the fund.

Negatives

• The disposition of shares at a higher price than the acquisition price suggests a partial exit or rebalancing by the fund.

Future Outlook

No specific future outlook or guidance is provided in this Form 4 filing, which primarily reports on past transactions.

Management Comments

• The stock option was granted to Kristina Burow in connection with her service on the board of directors of the Issuer.
• The net proceeds of the stock option exercise were remitted to ARCH Venture Fund IX, L.P., ARCH Venture Fund IX Overage, L.P., and ARCH Venture Fund X, L.P.
• Various ARCH Venture entities disclaim beneficial ownership except to the extent of any pecuniary interest therein.

Industry Context

StockSavvy.ai notes that Form 4 filings are standard for venture capital firms and other significant shareholders to report changes in their holdings, reflecting typical portfolio management activities.

Related Party Transactions

• The stock option was granted to Kristina Burow in connection with her service on the board of directors of the Issuer, indicating a transaction related to her role as a director.

Stakeholder Impact

• Shareholders may note the activity of a significant investor, which could influence market perception.
• The transactions reflect the investment strategy and portfolio management of ARCH Venture Funds.

Key Dates

Keywords

Form 4, SEC Filing, Beneficial Ownership, Stock Option, Common Stock, ARCH Venture Fund, Boundless Bio, Insider Trading, Venture Capital