Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. ☒ For the quarterly period ended September 30, 2025 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF ☐ For the transition period from ______ to ______ Commission file number: 001-38147 Core Natural Resources, Inc. (Exact name of registrant as specified in its charter) (Stat ...