| 1 | C & D Gas Co | Apollo, PA 15613-9714 | Oil & Gas Operator | Dec 2025 |
| 2 | Calarie Lee J & Lisa A | Rural Valley, PA 16249-4113 | Oil & Gas Operator | Dec 2025 |
| 3 | Campbell Oil & Gas Inc | Indiana, PA 15701-0278 | Oil & Gas Operator | Feb 2026 |
| 4 | Carnegie Natural Gas Co | Pittsburgh, PA 15236-1435 | Gas Operator | Dec 1991 |
| 5 | Carnegie Production Co | Charleston, WV 25328 | Oil & Gas Operator | Dec 2017 |
| 6 | Casella Charles J | Avonmore, PA 15618-1028 | Oil & Gas Operator | Dec 2015 |
| 7 | Castex Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2026 |
| 8 | Castle Exploration Company Inc | Blue Bell, PA 19422 | Oil & Gas Operator | May 2018 |
| 9 | Castle Gas Company Inc | Pittsburgh, PA 15236-2466 | Oil & Gas Operator | Dec 2007 |
| 10 | Catalyst Energy Inc | Pittsburgh, PA 15218 | Oil & Gas Operator | Feb 2026 |
| 11 | Chestnut Ridge Energy Of Pa LLC | Mineral Point, PA 15942-4411 | Gas Operator | Dec 2024 |
| 12 | Christine Marie Exploration LP | Indiana, PA 15701-0515 | Oil & Gas Operator | Dec 2025 |
| 13 | CNG Development Co | | Oil & Gas Operator | Dec 2008 |
| 14 | CNX Gas Company LLC | Canonsburg, PA 15317 | Oil & Gas Operator | Feb 2026 |
| 15 | Cobra Resources LLC | N Jackson, OH 44451 | Oil & Gas Operator | Dec 2025 |
| 16 | Columbia Natural Res Inc | Charleston, WV 25362-0070 | Gas Operator | Dec 2008 |
| 17 | Consol Gas Company | Canonsburg, PA 15317 | Oil & Gas Operator | Dec 2021 |
| 18 | Coolspring Gas & Oil Co LLC | Coolspring, PA 15730-8524 | Gas Operator | Dec 2025 |
| 19 | Coterra Energy Inc | Coraopolis, PA 15108-9862 | Oil & Gas Operator | Feb 2026 |