SCHEDULE: Invus Group Discloses 5% Stake in Abivax S.A.

Invus Public Equities and related entities have reported a 5.0% beneficial ownership stake in Abivax S.A., totaling 3,922,995 ordinary shares.

Summary

• Invus Public Equities, L.P., along with its controlling entities Invus Public Equities Advisors, LLC, Invus Global Management, LLC, Siren, L.L.C., and Raymond Debbane, collectively reported beneficial ownership of 3,922,995 ordinary shares of Abivax S.A.
• This ownership represents 5.0% of Abivax S.A.'s outstanding ordinary shares.
• The calculation is based on 77,830,067 shares outstanding as of September 30, 2025, as previously reported by Abivax S.A. in a Form 6-K filed on December 15, 2025.
• The reporting persons hold sole voting and dispositive power over all 3,922,995 shares.
• The shares are ordinary shares with a nominal value of Euro 0.01 per share, which are equivalent to American Depositary Shares (ADSs) quoted on the Nasdaq Global Market under the symbol "ABVX".

Sentiment

Score: 6

Explanation: StockSavvy.ai views this as a moderately positive signal, as the disclosure of a 5.0% beneficial ownership by Invus Public Equities suggests institutional confidence in Abivax S.A.'s long-term prospects.

Positives

• A significant institutional investor group, Invus Public Equities, has disclosed a 5.0% beneficial ownership stake in Abivax S.A., indicating a notable investment and potential confidence in the company's prospects.

Negatives

• NA

Risks

• NA

Future Outlook

NA

Industry Context

StockSavvy.ai notes that a 5.0% beneficial ownership stake by an investment group like Invus Public Equities in a biotechnology company such as Abivax S.A. can signal institutional confidence. Such a stake suggests that the investor sees long-term value or strategic potential, which is particularly relevant in the capital-intensive and research-driven biotech sector.

Comparison to Industry Standards

• This filing is a standard Schedule 13G disclosure, which is a regulatory requirement for investors acquiring more than 5% of a company's voting class of securities. The disclosure of a 5.0% stake by an institutional investor is a common occurrence across various industries, including biotechnology. There are no specific comparable companies, projects, or results mentioned in this filing to assess against industry standards beyond the regulatory compliance itself.

Stakeholder Impact

• Shareholders: The disclosure of a significant institutional stake may instill confidence among existing shareholders and potentially attract new investors, signaling a vote of confidence from a sophisticated investor.
• Management: Management may view this as validation of their strategy and potentially engage with the new significant shareholder.

Next Steps

• The reporting persons will be required to file further amendments to this Schedule 13G if there are material changes to their beneficial ownership, such as an increase or decrease of 1% or more, or if their intent changes from passive investment to influencing control.

Key Dates

Recommendation

This filing is a regulatory disclosure of beneficial ownership and does not contain operational or financial performance data to warrant a 'buy' or 'sell' recommendation. The establishment of a 5.0% stake by a sophisticated investor group like Invus Public Equities is a neutral to slightly positive signal, suggesting confidence in the company's long-term value. However, without further fundamental analysis of Abivax S.A.'s business, financials, and market position, a 'hold' recommendation is appropriate for existing investors, while potential investors should conduct further due diligence.

Keywords

Abivax S.A., ABVX, Invus Public Equities, Beneficial Ownership, Schedule 13G, Biotechnology, Pharmaceuticals, Institutional Investment, Equity Stake