Upi - A United States Steel Company company information, Employees & Contact Information

U. S. Steel Overview www.ussteel.com

Sustainability - Environmental - Water Quality and Conservation www.ussteel.com

United States Steel Corporation to Release First Quarter 2025 Financial Results on May 1, 2025 Business Wire

US Steel Sets Final Solo Earnings Date Before Nippon Steel Merger Stock Titan

Sustainability - Approach to Sustainability - United Nations SDGs www.ussteel.com

United States Steel Corporation Declares Dividend Business Wire

Sustainability - Approach to Sustainability - Material Topics and Stakeholder Engagement www.ussteel.com

United States Steel Corporation to Release Fourth Quarter and Full Year 2024 Financial Results on January 30, 2025 Business Wire

Mini Mill Steelmaking. Maximum Performance. www.ussteel.com

Food Security That Comes in a Can www.ussteel.com

U. S. Steel, Norfolk Southern, and Greenbrier Collaborate on New, Sustainable High-Strength Steel Railcar www.ussteel.com

HOW WE MAKE STEEL www.ussteel.com

About Us - Community Engagement www.ussteel.com

2024 MATERIALITY ASSESSMENT www.ussteel.com

QA with Our SVP and CTO www.ussteel.com

People: The Real Power of Community Engagement www.ussteel.com

U. S. Steel Battery-Powered Locomotives Receive “Governor’s Award for Environmental Excellence” from the Pennsylvania Department of Environmental Protection - www.ussteel.com www.ussteel.com

ADDRESSING CUSTOMER PAIN POINTS WITH WIN-WIN SOLUTIONS. www.ussteel.com

EXPERT SERVICES. INSPIRED SOLUTIONS. www.ussteel.com

Steel Packaging — A ‘Can Do’ All-American Industry www.ussteel.com

U. S. Steel Announces New Industry-Leading Warranty Policy for GALVALUME® Coated Steel Coils www.ussteel.com

U. S. Steel Secures NanoSteel® Patents to Expand Capabilities of World Class Advanced High-Strength Steel Offerings www.ussteel.com

U. S. Steel Powers Indiana Economy with Jobs and Local Investment Morningstar

U. S. Steel Announces Board of Directors Yahoo Finance

U. S. Steel Issues Updated Letter to Stockholders Yahoo Finance

U. S. Steel Comments on Ancora’s Blundering, Value-Destructive "Plan" Yahoo Finance

United States Steel Honors Employees for Community Service with $85,000 in Donations to Charitable Organizations Yahoo Finance

Bald Eagle Camera at U. S. Steel Irvin Plant Goes Live Business Wire

United States Steel Corporation Reports First Quarter 2025 Results Yahoo Finance

U. S. Steel to Fund Training Center with Multi-Million-Dollar Grant Following Close of Transaction with Nippon Steel Yahoo Finance

US Steel Q1 Guidance Shows Loss: Key Bright Spots in North American Operations Stock Titan

U. S. Steel Board Advances Capital Investments, Announces New Projects in Pennsylvania and Indiana Business Wire

United States Steel Corporation Declares Dividend Yahoo Finance

Automotive Expert Joins New U. S. Steel Podcast Yahoo Finance

US Steel Promises Major Growth: Thousands of New Jobs Coming Through Nippon Steel Partnership Stock Titan

U. S. Steel Releases Sustainability Report Emphasizing Progress Business Wire

U.S. Steel Stands Alone: Only Metals Company to Win Global Ethics Award in 2025 Stock Titan

Nippon Steel Corporation (NSC) to Acquire U. S. Steel, Moving Forward Together as the ‘Best Steelmaker with World-Leading Capabilities’ Business Wire

U. S. Steel Reacts to Important Department of Commerce Preliminary Results Yahoo Finance

United States Steel Celebrates Opening of DR-Grade Pellet Production Facility in Minnesota Business Wire

U. S. Steel Unlocks New Environmental Data for Customers with EPDs on Flat-Rolled Coil Products Melted at Big River Steel Works ESG Today

U. S. Steel Pioneers Battery-Powered Locomotives, Reinforces Commitment to Sustainability and Community Business Wire

U. S. Steel Secures NanoSteel® Patents to Expand Capabilities of World Class Advanced High-Strength Steel Offerings Business Wire

U. S. Steel Announces Strategic Alternatives Process ANTARA News

Terry Dunlap Elected to U. S. Steel Board of Directors citybiz

Andrea J. Ayers Elected to U. S. Steel Board of Directors Business Wire

United States Steel Corporation to Release Second Quarter 2023 Financial Results on July 27, 2023; Invites Retail and Institutional Investors to Submit Questions FinancialContent

United States Steel Corporation Announces Strategic Investment in Carnegie Foundry to Accelerate Advanced Robotics and Autonomy Capabilities Business Wire

EXHIBIT 99.1 SEC.gov

United States Steel (X): Company Profile, Stock Price, News, Rankings Fortune

United States Steel Corporation Announces Goal to Achieve Carbon Neutrality by 2050 Business Wire

United States Steel Corporation is First North American Steel Producer to Join ResponsibleSteelTM Business Wire

U. S. Steel Announces Sale of Transtar, LLC to Fortress Transportation and Infrastructure Investors LLC for $640 Million Business Wire

U. S. Steel Acquires Remaining 50 Percent Ownership GlobeNewswire

US Steel Reaches Tentative Agreement with United Steelworkers FinancialContent

U. S. Steel and the University of Michigan Solar Car Team Drive Sustainable Transportation FinancialContent

United States Steel Corporation to Release Second Quarter 2021 Financial Results on July 29, 2021 FinancialContent