Bpifrance Participations SA - 26 May 2026 SCHEDULE 13D/A Report for Constellium SE Ordinary Shares, nominal value EUR0.02 per share (CSTM)

Filing manager: Bpifrance Participations SA
Reporting owner: Bpifrance Participations S.A.
Security: Constellium SE Ordinary Shares, nominal value EUR0.02 per share
Beneficially owned shares: 8,403,903 shares
Class ownership: 6.2%
Large-stake signal: Form
SCHEDULE 13D/A
Active or control-oriented beneficial ownership filing.
Ownership
6.2%
Beneficial ownership of this reported class.
Shares
8,403,903 shares
Shares beneficially owned as disclosed.
Event date
26 May 2026
Date tied to the ownership event or amendment.
Accepted by SEC
28 May 2026
EDGAR acceptance date.
How to read this large-stake filing
Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
Compare this filing with the holder history and issuer page before treating the percentage as a current position.
Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
Symbol: CSTM
Shares outstanding: 135,546,823 shares
Form type: SCHEDULE 13D/A
Accepted by SEC: 28 May 2026, 16:01:16 UTC
Event date: 26 May 2026
SEC filing: View on sec.gov

Key filing fact

Bpifrance Participations SA disclosed 6.2% ownership in Constellium SE Ordinary Shares, nominal value EUR0.02 per share (CSTM) on 26 May 2026.

Key facts

Bpifrance Participations SA filed SCHEDULE 13D/A for Constellium SE Ordinary Shares, nominal value EUR0.02 per share (CSTM).
Disclosed ownership: 6.2%.
Date of event: 26 May 2026.

This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.

Backed by Schedule 13D/13G

Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.

Reporting persons

Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.

Name	Ownership	Shares owned	Shared voting power	Signature	Title	CIK
Caisse des Depots (CDC)	6.2%	8,403,903	8,403,903	/s/ Laurence Giraudon	Laurence Giraudon/ Chief Operating Officer, Finance and Operations Department, Asset Management Division
Bpifrance Participations S.A.	6.2%	8,403,903	8,403,903	/s/ Sophie Paquin	Sophie Paquin/Director of Legal Affairs	0001581835
Bpifrance S.A.	6.2%	8,403,903	8,403,903	/s/ Boubakar Dione	Boubakar Dione/Group Director of Legal Affairs	0001731118
EPIC Bpifrance	6.2%	8,403,903	8,403,903	/s/ Sophie Paquin	Sophie Paquin/Director of Legal Affairs	0001731121

CIK / CUSIP context first

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