| 1 | C & O Production | Nocona, TX 76255 | Oil & Gas Operator | Feb 2020 |
| 2 | Calumet Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2019 |
| 3 | Campbell, T. K. | Fort Worth, TX 76118 | Oil & Gas Operator | Mar 2006 |
| 4 | Canan Mowrey Operating, LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 5 | Canyon Operating LLC | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 6 | Ceja Corporation | Tulsa, OK 74172 | Oil & Gas Operator | Jul 2025 |
| 7 | Century Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 8 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 9 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Oct 2025 |
| 10 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 11 | Cholla Petroleum Inc | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 12 | Cico Oil & Gas Company | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 13 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 14 | Circle-S Energy, LLC | McKinney, TX 75071 | Oil & Gas Operator | Oct 2025 |
| 15 | Citrus Energy Corporation | Castle Rock, CO 80104 | Oil & Gas Operator | Mar 2020 |
| 16 | Claron Corporation | Houston, TX 77219 | Oil & Gas Operator | Oct 2025 |
| 17 | Clifton Oil | Muenster, TX 76252 | Oil & Gas Operator | Mar 2006 |
| 18 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 19 | Coda Energy, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1998 |
| 20 | Colt Resources Corporation | Billings, MT 59103 | Oil & Gas Operator | Feb 2013 |
| 21 | Confed Oil Incorporated | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2008 |
| 22 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 23 | Cooke & Montague Oper. Co., Inc. | Flower Mound, TX 75028 | Oil & Gas Operator | Oct 2025 |
| 24 | Cope Oil Company | Valley VIew, TX 76272 | Oil & Gas Operator | Feb 2015 |
| 25 | Corpening, Joe F. | Bowie, TX 76230 | Oil & Gas Operator | Oct 2013 |
| 26 | Cory, Kenneth W. LTD. | Bellaire, TX 77401 | Oil & Gas Operator | Oct 2025 |
| 27 | Couch, Harry L. | Odessa, TX 79762 | Oil & Gas Operator | Nov 1994 |
| 28 | Cox, Robert G. & Associates,Inc. | Dallas, TX 75225 | Oil & Gas Operator | Feb 1994 |
| 29 | CR Reed Production, Inc. | Gainesville, TX 76241 | Oil Operator | Oct 2025 |
| 30 | Crusader Energy Group Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 2015 |
| 31 | Crusader Energy Group LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Mar 2015 |
| 32 | Cso Consulting | Bridgeport, TX 76426 | Oil & Gas Operator | Mar 2020 |
| 33 | CTL Production, Inc. | Muenster, TX 76252 | Oil & Gas Operator | Oct 2025 |
| 34 | CVR Supply & Trading, LLC | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2024 |
| 35 | Cwic, Inc. | Granbury, TX 76049 | Oil & Gas Operator | Oct 2025 |