| 1 | C & D Gas Co | Apollo, PA 15613-9714 | Oil & Gas Operator | Dec 2025 |
| 2 | Caldera Resources LLC | Smicksburg, PA 16256-0055 | Gas Operator | Dec 2025 |
| 3 | Campbell Oil & Gas Inc | Indiana, PA 15701-0278 | Oil & Gas Operator | Mar 2026 |
| 4 | Canton Oil & Gas Co | Pleasantville, PA 16341-1729 | Oil & Gas Operator | Dec 2004 |
| 5 | Carlon Oil & Gas Co Inc | Derby, KS 67037 | Gas Operator | Dec 2025 |
| 6 | Carnegie Production Co | Charleston, WV 25328 | Oil & Gas Operator | Dec 2017 |
| 7 | Casella Charles J | Avonmore, PA 15618-1028 | Oil & Gas Operator | Dec 2015 |
| 8 | Castle Gas Company Inc | Pittsburgh, PA 15236-2466 | Oil & Gas Operator | Dec 2007 |
| 9 | Chestnut Ridge Energy Of Pa LLC | Mineral Point, PA 15942-4411 | Gas Operator | Dec 2025 |
| 10 | Christine Marie Exploration LP | Indiana, PA 15701-0515 | Oil & Gas Operator | Dec 2025 |
| 11 | Clifford & Scott McKeever | Clarksburg, PA 15725 | Gas Operator | Dec 2024 |
| 12 | CNG Development Co | | Oil & Gas Operator | Dec 2008 |
| 13 | CNX Gas Company LLC | Canonsburg, PA 15317 | Oil & Gas Operator | Mar 2026 |
| 14 | Columbia Gas Trans LLC | Charleston, WV 25325-1273 | Gas Operator | Dec 1987 |
| 15 | Columbia Natural Res Inc | Charleston, WV 25362-0070 | Gas Operator | Dec 2008 |
| 16 | Consol Gas Company | Canonsburg, PA 15317 | Oil & Gas Operator | Dec 2021 |
| 17 | Coolspring Gas & Oil Co LLC | Coolspring, PA 15730-8524 | Gas Operator | Dec 2025 |
| 18 | Coterra Energy Inc | Coraopolis, PA 15108-9862 | Oil & Gas Operator | Mar 2026 |