# EDGAR Filing Document

**Accession Number:** 0001710366
**File Stem:** 0001710366-26-000018
**Filing Date:** 2026-3
**Character Count:** 2848
**Document Hash:** 2243845b477831c5914504489caac8e7
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001710366-26-000018.hdr.sgml**: 20260316

**ACCESSION NUMBER**: 0001710366-26-000018

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20260316

**DATE AS OF CHANGE**: 20260316

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Core Natural Resources, Inc.
- **CENTRAL INDEX KEY:** 0001710366
- **STANDARD INDUSTRIAL CLASSIFICATION:** BITUMINOUS COAL & LIGNITE MINING [1220]
- **ORGANIZATION NAME:** 01 Energy & Transportation
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DC
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38147
- **FILM NUMBER:** 26754904

**BUSINESS ADDRESS:**
- **STREET 1:** 275 TECHNOLOGY DRIVE
- **STREET 2:** SUITE #101
- **CITY:** CANONSBURG
- **STATE:** PA
- **ZIP:** 15317
- **BUSINESS PHONE:** 724-416-8300

**MAIL ADDRESS:**
- **STREET 1:** 275 TECHNOLOGY DRIVE
- **STREET 2:** SUITE #101
- **CITY:** CANONSBURG
- **STATE:** PA
- **ZIP:** 15317

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CONSOL Energy Inc.
- **DATE OF NAME CHANGE:** 20171128

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CONSOL Mining Corp
- **DATE OF NAME CHANGE:** 20170626

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**SCHEDULE 14A**

**(Rule 14a-101)**

**INFORMATION REQUIRED IN PROXY STATEMENT**

**SCHEDULE 14A INFORMATION**

**Proxy Statement Pursuant to Section 14(a) of the**

**Securities Exchange Act of 1934**

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| | | |
|:---|:---|:---|
| Filed by the Registrant ☒ | Filed by the Registrant ☒ | Filed by a party other than the Registrant ☐ |
| Check the appropriate box: | Check the appropriate box: |  |
| &nbsp;&nbsp;&nbsp;☐ | Preliminary Proxy Statement |  |
| &nbsp;&nbsp;&nbsp;☐ | **Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))** | **Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))** |
| &nbsp;&nbsp;&nbsp;☐ | Definitive Proxy Statement |  |
| ☒ | Definitive Additional Materials |  |
| &nbsp;&nbsp;&nbsp;☐ | Soliciting Material Pursuant to § 240.14a-12 |  |

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**Core Natural Resources, Inc.**

**(Name of Registrant as Specified in its Charter)**

**Not applicable.**

**(Name of Person(s) Filing Proxy Statement, if other than the Registrant)**

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| | |
|:---|:---|
| Payment of Filing Fee (Check all boxes that apply): | Payment of Filing Fee (Check all boxes that apply): |
| ☒ | No fee required |
| &nbsp;&nbsp;&nbsp;☐ | Fee paid previously with preliminary materials |
| &nbsp;&nbsp;&nbsp;☐ | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11 |

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