Nippon Steel & USS Acquisition Overview

Forward-Looking Statements This presentation contains information regarding U. S. Steel 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 future operating or financial results, operating or financial performance, trends, events or developments that we expect or anticipate will occur in the future, anticipated cost savings, potential capital and operational cash improvements and changes in the global economic environment, 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 U. S. Steel'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 U. S. Steel's or NSC's control. It is possible that U. S. Steel's or NSC's actual results and financial condition may differ, possibly materially, from the anticipated results and financial condition indicated in these forward-looking statements. Management of U. S. Steel 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 U. S. Steel'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 timing, receipt and terms and conditions of any required governmental and regulatory approvals of the proposed transaction that could cause the parties to terminate the definitive agreement and plan of merger relating to the proposed transaction (the "Merger Agreement"); the occurrence of any event, change or other circumstances that could give rise to the termination of the Merger Agreement; the possibility that U. S. Steel's stockholders may not approve the proposed transaction; the risks and uncertainties related to securing the necessary stockholder approval; the risk that the parties to the Merger 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; certain restrictions during the pendency of the proposed transaction that may impact U. S. Steel'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 U. S. Steel'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 of any litigation relating to the proposed transaction; and the risk that the proposed transaction and its announcement could have an adverse effect on the ability of U. S. Steel 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 U. S. Steel. U. S. Steel directs readers to its Form 10-K for the year ended December 31, 2022 and Quarterly Report on Form 10-Q for the quarter ended September 30, 2023, and the other documents it files with the SEC for other risks associated with U. S. Steel'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. Risks related to NSC's forward-looking statements include, but are not limited to, changes in regional and global macroeconomic conditions, particularly in Japan, China and the United States; excess capacity and oversupply in the steel industry; unfair trade and pricing practices in regional markets; the possibility of low steel prices or excess iron ore supply; the possibility of significant increases in market prices of essential raw materials; the possibility of depreciation of the value of the Japanese yen against the U.S. dollar and other major foreign currencies; the loss of market share to substitute materials; NSC's ability to reduce costs and improve operating efficiency; the possibility of not completing planned alliances, acquisitions or investments, or such alliances, acquisitions or investments not having the anticipated results; natural disasters and accidents or unpredictable events which may disrupt NSC's supply chain as well as other events that may negatively impact NSC's business activities; risks relating to CO2 emissions and NSC's challenge for carbon neutrality; the economic, political, social and legal uncertainty of doing business in emerging economies; the possibility of incurring expenses resulting from any defects in our products or incurring additional costs and reputational harm due to product defects of other steel manufacturers; the possibility that we may be unable to protect our intellectual property rights or face intellectual property infringement claims by third parties; changes in laws and regulations of countries where we operate, including trade laws and tariffs, as well a tax, environmental, health and safety laws; and the possibility of damage to our reputation and business due to data breaches and data theft. All information in this presentation is as of the date above. Neither U. S. Steel nor NSC undertakes any duty to update any forward-looking statement to conform the statement to actual results or changes in U. S. Steel's or NSC's expectations whether as a result of new information, future events or otherwise, except as required by law. NIPPON STEEL USS United States Steel Corporation 24