| 1 | C & E Operating, Inc. | Hockley, TX 77447 | Oil & Gas Operator | Oct 2025 |
| 2 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Jun 2025 |
| 3 | Cabot Oil & Gas Production Corp. | Houston, TX 77060 | Oil & Gas Operator | Jun 1996 |
| 4 | Cal-Tex Exploration & Production Company LLC | San Antonio, TX 78228 | Oil & Gas Operator | Oct 2025 |
| 5 | Caltex Energy Co. | Luling, TX 78648 | Oil & Gas Operator | Oct 2025 |
| 6 | Cantera Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2017 |
| 7 | Canyon Creek Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 8 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 9 | CB Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Nov 2017 |
| 10 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 11 | Christico Petroleum Company | San Antonio, TX 78216 | Oil & Gas Operator | Oct 2025 |
| 12 | Cimarron Engineering Corp. | Kingsville, TX 78364 | Oil & Gas Operator | May 2015 |
| 13 | Cimarron Engineering, LLC | Kingsville, TX 78364 | Oil & Gas Operator | Oct 2025 |
| 14 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 15 | Cody Energy LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2020 |
| 16 | Collins Resources, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Mar 2011 |
| 17 | Cometra Oil And Gas, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 1997 |
| 18 | Comstock Oil & Gas, Inc. | Frisco, TX 75034 | Oil & Gas Operator | Dec 2012 |
| 19 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 20 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 21 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 22 | Corpus Christi Leaseholds, Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Sep 1996 |
| 23 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 24 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 25 | Cotton, W. L. | Hebbronville, TX 78361 | Oil & Gas Operator | Mar 1996 |
| 26 | Cotton, W.L. Gems & Minerals LTD | Hebbronville, TX 78361 | Oil & Gas Operator | May 2000 |
| 27 | Crimson Exploration Oper., Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 28 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |