Ownership Filing for Nathan J. Tucker

This filing reports on the ownership of Core Natural Resources, Inc. (CNR) by Nathan J. Tucker, SVP & Chief Financial Officer. Following a transaction, Mr. Tucker directly owns 1,590 shares of Common Stock. Of these, 690 shares are unvested restricted stock units, which are contingent rights to receive one share of common stock upon vesting according to the award agreement. The filing is dated August 20, 2026, based on the reporting period of August 18, 2026.