2019 Title of Each Class Trading Symbol Name of Exchange on which Registered United States Steel Corporation Common Stock, par value $1.00 X New York Stock Exchange United States Steel Corporation Common Stock, par value $1.00 X Chicago Stock Exchange UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Fiscal Year Ended December 31, 2019 Or ☐ TRANSITION REPORT PURSUANT TO S ...