CFO — Nathan Tucker: The filing discloses the internal promotion of Nathan Tucker to CFO as part of a planned succession process, while the outgoing CFO transitions to an expanded role as President rather than leaving the company.

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the "Company," "we," "us," or "our") issued a press release on August 6, 2026 announcing its 2026 second quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our web…

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the "Company," "we," "us," or "our") issued a press release on May 7, 2026 announcing its 2026 first quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our website…

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the "Company," "we," "us," or "our") issued a press release on February 12, 2026 announcing its 2025 fourth quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our…

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the "Company," "we," "us," or "our") issued a press release on November 6, 2025 announcing its 2025 third quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our we…

CEO — Paul A. Lang: Mr. Paul A. Lang resigned as CEO and from the Board, with James A. Brock appointed as new CEO.

and the Exhibit 99.1 shall be considered “furnished” and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”), nor shall it be deemed incorporated by reference into any reports or filings with the Securities and Exchange Commission (the “SEC”), whether made before or after…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth in

Entry into a Material Definitive Agreement. On July 28, 2025 (the “Closing Date”), Core Natural Resources, Inc. (“Core” or the “Company”) and certain subsidiaries of Core entered into (i) that certain Receivables Financing Agreement (the “Receivables Financing Agreement”), by and among Core Receivable Company, LLC (the “Borrower”), as borrower, Core Sales, LLC, as the initial servicer (the “Servicer”), PNC Bank, National Association (“PNC”), as administrative agent and LC bank, PNC Capital Ma…

Termination of Material Definitive Agreement. The information set forth in

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the “Company,” “we,” “us,” “our”) issued a press release on May 8, 2025 announcing its 2025 first quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our website in…

Results of Operations and Financial Condition. Core Natural Resources, Inc. (the “Company,” “we,” “us,” “our”) issued a press release on February 20, 2025 announcing its 2024 fourth quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.corenaturalresources.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our web…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth in

by reference. At the effective time of the Merger (the “Effective Time”), each share of Class A common stock, par value $0.01 per share, and Class B common stock, par value $0.01 per share, of Arch issued and outstanding immediately prior to the Effective Time (other than certain excluded shares as described in the Merger Agreement) was automatically converted into the right to receive 1.326 shares of common stock, par value $0.01 per share (the “Exchange Ratio”), of the Company (“Company Com…

Other Matters. On January 13, 2025, the Company purchased an aggregate principal amount of $98.1 million of the outstanding (i) Solid Waste Disposal Facility Revenue Bonds (Arch Resources Project), Series 2020, and (ii) Solid Waste Disposal Facility Revenue Bonds (Arch Resources Project), Series 2021 (together, the “Arch Bonds”), which were issued by the West Virginia Economic Development Authority for the benefit of Arch. The Company also consented to the release of all liens, mortgages and…

Entry into a Material Definitive Agreement. Amendment to Revolving Credit Facility On January 14, 2025, and in connection with the Merger, the Company entered into Amendment No. 6 (the “Credit Facility Amendment”), which amends its existing Credit Agreement, dated as of November 28, 2017 (as amended, restated, amended and restated, supplemented or otherwise modified, the “Credit Agreement”), by and among the Company, the subsidiary guarantors party thereto, PNC Bank, National Association (“PN…

Director — John T. Mills: The filing describes a board reconstitution and director resignation/appointment resulting from a merger, which is a structural governance change rather than a sudden loss of a senior executive officer.

Material Modification to Rights of Security Holders. The information set forth in

Other Events. As previously disclosed, on August 20, 2024, CONSOL Energy Inc., a Delaware corporation (“CONSOL”), entered into an Agreement and Plan of Merger (as it may be amended from time to time, the “merger agreement”) with Arch Resources, Inc., a Delaware corporation (“Arch”), and Mountain Range Merger Sub Inc., a Delaware corporation and a wholly owned subsidiary of CONSOL (“Merger Sub”). The merger agreement provides that, upon the terms and subject to the conditions set forth therein…

Chief Accounting Officer — John Rothka: The filing discloses the payment of a retention bonus to an officer, which is a compensatory arrangement rather than a change in management status or departure.

General Counsel — Martha A. Wiegand: The filing discloses the negotiated separation and severance agreement for the General Counsel, a senior officer, without indicating a sudden crisis or termination for cause.

Results of Operations and Financial Condition. CONSOL Energy Inc. (the "Company," "we," "us," "our") issued a press release on November 5, 2024 announcing its 2024 third quarter results. A copy of the press release is attached to this Form 8-K as Exhibit 99.1. Please refer to our website at www.consolenergy.com for additional information regarding the Company. For example, periodically during the quarter, we may provide investor presentations, which would appear on our website in the Investor…

Other Events. On October 14, 2024, CONSOL Energy Inc., a Delaware corporation (“CONSOL”), and Arch Resources, Inc., a Delaware corporation (“Arch”), issued a joint press release announcing that the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, in relation to the pending combination of CONSOL and Arch expired at 11:59 p.m. Eastern Time on October 11, 2024. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference h…

Other Events. In connection with the execution of the Merger Agreement, the board of directors of CONSOL declared a dividend equal to $0.25 per share of CONSOL Common Stock. The dividend will be payable in cash on September 13, 2024 to holders of record of CONSOL Common Stock as of the close of business on August 30, 2024. On August 21, 2024, CONSOL and Arch issued a joint press release announcing that they had entered into the Merger Agreement. A copy of the press release is attached hereto…

Entry into a Material Definitive Agreement. On August 20, 2024, CONSOL Energy Inc., a Delaware corporation (“CONSOL”), entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Mountain Range Merger Sub Inc., a Delaware corporation and a wholly owned subsidiary of CONSOL (“Merger Sub”), and Arch Resources, Inc., a Delaware corporation (“Arch”). The Merger Agreement provides for the combination of CONSOL and Arch in an all-stock merger of equals transaction upon the terms and…