UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): June 16, 2025 (June 13, 2025)

United States Steel Corporation

(Exact Name of Registrant as Specified in Charter)

600 Grant Street,

Pittsburgh, PA 15219-2800

(Address of Principal Executive Offices, and Zip Code)

(412) 433-1121

Registrant’s Telephone Number, Including Area Code

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).  

Emerging growth company ¨

If an emerging growth company, indicate 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. ¨  

As previously disclosed, on December 18, 2023, United States Steel Corporation (the “Company”) entered into an Agreement and Plan of Merger (such agreement, as it may be amended, modified or supplemented from time to time, the “Agreement”) by and among the Company, Nippon Steel North America, Inc., a New York corporation (“Parent”), 2023 Merger Subsidiary, Inc., a Delaware corporation and a wholly owned subsidiary of Parent, and solely as provided in Section 9.13 therein, Nippon Steel Corporation, a Japanese corporation (“NSC”).

On June 13, 2025, President Trump issued an executive order (the “Order”) finding that the threatened impairment to U.S. national security arising as a result of the transaction contemplated by the Agreement (the “Transaction”) could be adequately mitigated through entry into and compliance with a national security agreement on terms determined by the U.S. government. On June 13, 2025, the Company, Parent and NSC entered into a qualifying national security agreement with the U.S. government. A copy of the joint press release issued by the Company and NSC announcing the issuance of the Order and entry into the national security agreement is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

All regulatory approvals required for the completion of the Transaction have been received. The Transaction remains subject to the satisfaction of customary closing conditions, and is expected to be completed promptly.

(d) Exhibits:

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Current Report on Form 8-K contains information regarding the Company and NSC that may constitute “forward-looking statements,” as that term is defined under the Private Securities Litigation Reform Act of 1995 and other securities laws, that are subject to risks and uncertainties. We intend the forward-looking statements to be covered by the safe harbor provisions for forward-looking statements in those sections. Generally, we have identified such forward-looking statements by using the words “believe,” “expect,” “intend,” “estimate,” “anticipate,” “project,” “target,” “forecast,” “aim,” “should,” “plan,” “goal,” “future,” “will,” “may” and similar expressions or by using future dates in connection with any discussion of, among other things, statements expressing general views about trends, events or developments that we expect or anticipate will occur in the future, potential changes in the global economic environment, anticipated capital expenditures, the construction or operation of new or existing facilities or capabilities and the costs associated with such matters, as well as statements regarding the proposed transaction, including the timing of the completion of the transaction. However, the absence of these words or similar expressions does not mean that a statement is not forward-looking. Forward-looking statements include all statements that are not historical facts, but instead represent only the Company’s and NSC’s beliefs regarding future goals, plans and expectations about our prospects for the future and other events, many of which, by their nature, are inherently uncertain and outside of the Company’s or NSC’s control and may differ, possibly materially, from the anticipated events indicated in these forward-looking statements. Management of the Company or NSC, as applicable, believes that these forward-looking statements are reasonable as of the time made. However, caution should be taken not to place undue reliance on any such forward-looking statements because such statements speak only as of the date when made. In addition, forward looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from the Company’s or NSC’s historical experience and our present expectations or projections. Risks and uncertainties include without limitation: the ability of the parties to consummate the proposed transaction, on a timely basis or at all; the occurrence of any event, change or other circumstances that could give rise to the termination of the definitive agreement and plan of merger relating to the proposed transaction (the “Agreement”); risks arising from transaction-related litigation, either brought by or against the parties; the risk that the parties to the Agreement may not be able to satisfy the conditions to the proposed transaction in a timely manner or at all; risks related to disruption of management time from ongoing business operations due to the proposed transaction and related litigation; certain restrictions during the pendency of the proposed transaction that may impact the Company’s or NSC’s ability to pursue certain business opportunities or strategic transactions; the risk that any announcements relating to the proposed transaction could have adverse effects on the market price of the Company’s common stock or NSC’s common stock or American Depositary Receipts; the risk of any unexpected costs or expenses resulting from the proposed transaction; the risk that the proposed transaction and its announcement could have an adverse effect on the ability of the Company or NSC to retain customers and retain and hire key personnel and maintain relationships with customers, suppliers, employees, stockholders and other business relationships and on its operating results and business generally; and the risk the pending proposed transaction could distract management of the Company. The Company directs readers to its Form 10-K for the year ended December 31, 2024 and Quarterly Report on Form 10-Q for the quarter ended March 31, 2025, and the other documents it files with the SEC for other risks associated with the Company’s future performance. These documents contain and identify important factors that could cause actual results to differ materially from those contained in the forward-looking statements.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: June 16, 2025