CONSTELLIUM SE

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

For the quarterly period ended March 31, 2026

OR

For the transition period from _________ to __________

Commission file number:001-35931

Constellium SE

(Exact name of registrant as specified in its charter)

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange

Act of 1934 during the preceding 12 months, (or for such shorter period that the registrant was required to file such reports), and (2) has been

subject to such filing requirements for the past 90 days.☑ Yes ☐ No

Indicate by check mark whether the registrant submitted electronically every Interactive Data File required to be submitted pursuant to Rule

405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required

to submit such files).☑ Yes ☐ No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting

company or emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company", and

"emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicated by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). ☐ Yes☑ No

The number of outstanding ordinary shares of the registrant on March 31, 2026, was 136,150,450 shares.

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Explanatory Note

Constellium SE (“Constellium SE” or “the Company”, and when referred to together with its subsidiaries, “the Group”

or “Constellium”), is a corporation organized under the laws of France. On June 30, 2025, the Company determined it no longer

qualified as a “foreign private issuer,” as determined by Rule 3b-4 under the Securities Exchange Act of 1934, as amended (the

“Exchange Act”). As from January 1, 2026, when its earlier submission to the US securities law requirements applicable to a

domestic issuer ceased to be voluntary, the Company will continue to file annual reports on Form 10-K, quarterly reports on

Form 10-Q, current reports on Form 8-K, and comply with all other obligations applicable to companies not qualifying as

“foreign private issuers” as set forth by the New York Stock Exchange and the Securities and Exchange Commission (“SEC”).

Constellium SE’s I.R.S. Employer Identification Number is: 98-0667516. The Group’s U.S. assets are held by

Constellium US Holdings I, LLC, a wholly owned subsidiary of Constellium SE. The I.R.S. Employer Identification Number of

Constellium US Holdings I, LLC is: 27-4126819.

Forward-Looking Statements

This report contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act

of 1995. You can identify certain forward-looking statements because they contain words such as, but not limited to,

“anticipates,” “believes,” “could,” ”estimates,” “expects,” “forecasts,” “intends,” “likely,” “may,” “plans,” “should,” “targets,”

“will,” or “would,” and similar expressions (or the negative of these terminologies or expressions). Forward-looking statements

do not relate strictly to historical or current facts and reflect management’s current assumptions, beliefs, expectations,

objectives, plans and projections about the future, including with respect to our business, results of operations and financial

condition. Accordingly, forward-looking statements are subject to uncertainties, risks and changes that are difficult to predict

and many of which are outside of our control. Such factors include, but are not limited to: market competition; global or

regional economic downturns or adverse changes in industry-specific conditions, including the impacts of tax and tariff

programs, inflation, foreign currency exchange, and industry consolidation; disruption to business operations; natural disasters,

including severe flooding and other weather-related events; geopolitical tensions and conflicts, including the ongoing conflict

between Russia and Ukraine and the ongoing conflict involving the United States, Israel and Iran; the inability to meet customer

demand and quality requirements; the loss of key customers, suppliers or other business relationships; supply disruptions;

excessive inflation; potential capacity constraints or lack of effectiveness of our hedging policy activities; the loss of key

employees; levels of indebtedness that could limit our operating flexibility and opportunities; as well as the risk factors set forth

in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. If underlying assumptions prove

inaccurate, or known or unknown risks or uncertainties materialize, actual results could vary materially from expectations

expressed or implied in the forward-looking statements. Investors are cautioned not to place undue reliance on any such

forward-looking statements, which speak only as of the date they are made. We undertake no obligation to update any forward-

looking statement, whether because of new information, future events or otherwise, except as required by law.

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