Core Natural Resources, Inc.

Our operations are subject to a variety of risks and disputes normally incidental to our business. As a result, we may, at any given time, be a defendant in various legal proceedings and litigation arising in the ordinary course of business. We are not currently subject to any material litigation other than those described in Note 14—Commitments and Contingent Liabilities in the Notes to the Condensed Consolidated Financial Statements in this Report, which descriptions are incorporated herein by this reference.

SEC regulations require us to disclose certain information about environmental proceedings if we reasonably believe that such proceedings may result in monetary sanctions above a stated threshold. We use a threshold of $1 million for purposes of determining whether disclosure of any such proceedings is required, as permitted pursuant to Item 103(c)(3)(iii) of Regulation S-K. No such environmental proceedings were pending or contemplated as of March 31, 2026.