| 1 | C & T Energy Of East Canton Inc | East Canton, OH 44730 | Oil & Gas Operator | Dec 2024 |
| 2 | C T R Resources Inc | Alliance, OH 44601 | Oil & Gas Operator | Dec 2013 |
| 3 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 4 | Cameron & Kincaid | Zanesville, OH 43701 | Oil & Gas Operator | Dec 1986 |
| 5 | Cameron Brothers | Zanesville, OH 43701 | Oil & Gas Operator | Dec 1995 |
| 6 | Cameron Production Co Inc | Zanesville, OH 43701 | Oil & Gas Operator | Dec 2024 |
| 7 | Camphire George E. | Danville, OH 43014 | Oil & Gas Operator | Dec 2024 |
| 8 | Capstone Oil Producing LLC | Millersburg, OH 44654 | Oil & Gas Operator | Dec 2024 |
| 9 | Carroll Resources | Loudonville, OH 44842 | Oil & Gas Operator | Dec 1998 |
| 10 | Cascade Petroleum Inc | North Canton, OH 44720-4244-4244 | Oil & Gas Operator | Dec 1992 |
| 11 | Central Energy Co Inc | Newark, OH 43055 | Oil & Gas Operator | Dec 1998 |
| 12 | Cgas Exploration | Charleston, WV 25301 | Oil & Gas Operator | Dec 2006 |
| 13 | Chesapeake Appalachia LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2025 |
| 14 | Chevron Appalachia, LLC | Corapolis, PA 15108 | Oil & Gas Operator | Jul 2020 |
| 15 | Christa Oil Co | Cumberland, OH 43732 | Oil & Gas Operator | Nov 1999 |
| 16 | Clinton Gas Marketing Inc | Columbus, OH 43214 | Oil & Gas Operator | Dec 1988 |
| 17 | Collins-McGregor Operating Company | Marietta, OH 45750 | Oil & Gas Operator | Dec 2024 |
| 18 | Columbia Gas Transmission, LLC | Charleston, WV 25314 | Oil & Gas Operator | Dec 2021 |
| 19 | Curry R D Production Co | Memphis, TN 38103 | Oil & Gas Operator | Dec 1986 |