| 1 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Jul 2025 |
| 2 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Oct 2025 |
| 3 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 4 | Cheyenne Petroleum Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 2025 |
| 5 | Choctaw Gas Company | Quinton, OK 74561 | Gas Operator | Jun 2025 |
| 6 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Oct 2025 |
| 7 | Cleary Petroleum Corporation | Edmond, OK 73083 | Oil & Gas Operator | Jul 2019 |
| 8 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 9 | Concorde Resources Corporation | Eufaula, OK 74432 | Oil & Gas Operator | May 2025 |
| 10 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 11 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 12 | Coquina Oil Corporation | Houston, TX 77227 | Oil & Gas Operator | Mar 2015 |
| 13 | Corman, Jack | Dallas, TX 75231 | Oil & Gas Operator | May 2022 |
| 14 | Cortez Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2016 |
| 15 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 16 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 17 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 18 | Cross Timbers Production Co | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 2005 |
| 19 | Crow Creek Operating Co III LLC | Tulsa, OK 74137-8432 | Oil & Gas Operator | Apr 2015 |