SCHEDULE: Citadel Entities Adjust Boundless Bio Stake

Citadel entities have updated their beneficial ownership filings for Boundless Bio, Inc., reporting a combined 0.6% stake.

Summary

• This filing is an amendment to a Schedule 13G, indicating a change in beneficial ownership of Boundless Bio, Inc. common stock.
• Citadel Securities LLC now beneficially owns 65,617 shares, representing 0.3% of the class.
• Citadel Securities Group LP, Citadel Securities GP LLC, and Kenneth Griffin each beneficially own 145,118 shares, representing 0.6% of the class.
• Other reporting entities, including Citadel Advisors LLC, Citadel Advisors Holdings LP, and Citadel GP LLC, report 0 shares beneficially owned.
• The percentages are based on 22,474,777 shares outstanding as of June 15, 2026.

Sentiment

Score: 3

Explanation: StockSavvy.ai views this as a neutral filing, primarily reporting changes in beneficial ownership without new material financial or strategic information.

Positives

• The filing clarifies the beneficial ownership structure of Citadel entities concerning Boundless Bio, Inc.
• The reporting entities are acting in compliance with SEC disclosure requirements.

Negatives

• The filing does not provide any new financial performance data or strategic updates for Boundless Bio, Inc.
• The reported ownership stakes are relatively small, suggesting no significant control or influence by these entities.

Risks

• The filing itself does not introduce new risks, but the underlying business of Boundless Bio, Inc. may be subject to risks detailed in its other SEC filings.

Future Outlook

This filing does not contain any forward-looking statements or guidance regarding Boundless Bio, Inc.'s future performance.

Industry Context

StockSavvy.ai notes that Schedule 13G filings are routine disclosures for institutional investors and do not typically signal significant shifts in company strategy or performance unless they represent a substantial change in ownership percentage or intent.

Stakeholder Impact

• Shareholders: The filing provides transparency regarding ownership by significant financial entities, which can be a factor in market perception, though the current stakes are small.

Next Steps

• The reporting persons will continue to file amendments to Schedule 13G as required by SEC regulations for any material changes in their beneficial ownership.

Key Dates

Keywords

Schedule 13G, Beneficial Ownership, Citadel, Boundless Bio, Securities, Investment