| 1 | C & D Resources, Inc. | | Oil & Gas Operator | Nov 2001 |
| 2 | C. L. Brown, III | | Oil Operator | Dec 1991 |
| 3 | C. L. Brown, Inc. | | Oil Operator | Dec 1999 |
| 4 | C6 Operating, L.L.C. | Keatchie, LA 71046 | Oil & Gas Operator | Oct 2025 |
| 5 | Cajun Minerals, Inc. | | Oil & Gas Operator | Mar 1997 |
| 6 | Cala Oil & Gas | | Oil & Gas Operator | Oct 1997 |
| 7 | Camex Operating Company | | Oil & Gas Operator | Dec 2024 |
| 8 | Camex, Inc. | | Oil & Gas Operator | Jun 1992 |
| 9 | Candice Venture #1 | | Oil & Gas Operator | May 1992 |
| 10 | Cardinal Oil & Gas, Inc. | | Oil & Gas Operator | Jun 1995 |
| 11 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 12 | Carrollton Resources Corp. | | Oil & Gas Operator | Sep 2000 |
| 13 | Caspen Oil, Inc. | Denver, CO 80226 | Oil & Gas Operator | Jul 1993 |
| 14 | Caspen Operating Company | Somerset, TX 78069 | Oil & Gas Operator | Mar 2008 |
| 15 | Castex Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 16 | Castor Production, L.L.C. | | Oil Operator | Dec 2024 |
| 17 | Celeron Oil & Gas Company | | Oil & Gas Operator | Dec 1987 |
| 18 | Cenla Oil Company, LLC | | Oil Operator | Dec 2024 |
| 19 | Central Crude, Inc. | | Oil & Gas Operator | Jul 2014 |
| 20 | Central Resources Inc | Denver, CO 80203 | Oil & Gas Operator | Dec 2019 |
| 21 | Chaparral Energy, Inc. | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2009 |
| 22 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Oct 2025 |
| 23 | Charles F. Word & Associates | | Oil Operator | Dec 1978 |
| 24 | Charleston Oil & Gas, Inc. | | Oil & Gas Operator | Mar 1997 |
| 25 | Chestnut Exploration And Production, Inc. | Richardson, TX 78081 | Oil & Gas Operator | Nov 2020 |
| 26 | Chestnut Petroleum, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Nov 2011 |
| 27 | Chevron Pipe Line Company | Houston, TX 77001 | Oil Operator | Feb 2015 |
| 28 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 29 | Christeve Oil Company, Inc. | Houston, TX 77068 | Oil & Gas Operator | Dec 2022 |
| 30 | Churchill Energy Inc | | Oil & Gas Operator | Sep 2020 |
| 31 | Cibco Resources, LLC | | Oil & Gas Operator | Nov 2024 |
| 32 | Claron Corporation | Houston, TX 77219 | Oil & Gas Operator | Oct 2025 |
| 33 | Clayton W. Williams, Jr. | | Oil & Gas Operator | Sep 1986 |
| 34 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 35 | CNG Producing Co.-Tulsa Div. | | Oil & Gas Operator | Jun 1986 |
| 36 | CNG Producing Company | New Orleans, LA 70112 | Oil & Gas Operator | Dec 2015 |
| 37 | Coast Exploration Co. | | Oil & Gas Operator | Nov 1997 |
| 38 | Coastal Minerals, Inc. | | Oil Operator | Aug 1991 |
| 39 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 40 | Coastal Plains Exploration, LLC | Port Lavaca, TX 77979 | Oil & Gas Operator | Oct 2025 |
| 41 | Coastal Production Inc. | | Oil & Gas Operator | Aug 2000 |
| 42 | Conn Energy Group, LLC | | Oil & Gas Operator | Apr 2024 |
| 43 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 44 | Consolidated Resources Inc | | Oil & Gas Operator | May 2004 |
| 45 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 46 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 47 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 48 | Coteau Energy LLC | | Oil & Gas Operator | Dec 2024 |
| 49 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 50 | Cox Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2014 |
| 51 | CPBG, LLC | | Oil Operator | Oct 2019 |
| 52 | Crain & Dore Production Co Inc | | Oil & Gas Operator | Oct 1990 |
| 53 | Crawford Energy Operating Co | Houston, TX 77056 | Oil & Gas Operator | Aug 2008 |
| 54 | Crawford Hughes Operating Co. | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 55 | Crimson Explor Operating, Inc. | | Oil & Gas Operator | Dec 2009 |
| 56 | CSV Holdings, Inc. | | Oil & Gas Operator | Dec 2014 |
| 57 | Culoco, Inc. | Dallas, TX 75374 | Oil & Gas Operator | Nov 2024 |
| 58 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 59 | Cypress Production, Inc. | Azle, TX 76020 | Oil & Gas Operator | Oct 2025 |