| 1 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Aug 2024 |
| 2 | Camex Operating Company | | Oil & Gas Operator | Jun 2024 |
| 3 | Camex, Inc. | | Oil & Gas Operator | Jun 1992 |
| 4 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 5 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Nov 2024 |
| 6 | Carrollton Resources Corp. | | Oil & Gas Operator | Sep 2000 |
| 7 | Caskids Operating Company | Houston, TX 77027 | Oil & Gas Operator | Nov 2024 |
| 8 | Caspen Operating Company | Somerset, TX 78069 | Oil & Gas Operator | Mar 2008 |
| 9 | Castex Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Nov 2024 |
| 10 | Cathexis Oil & Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2014 |
| 11 | Century Exploration Houston, Inc | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2011 |
| 12 | Century Exploration N.O., Inc. | | Oil & Gas Operator | Sep 2011 |
| 13 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Nov 2024 |
| 14 | Cholla Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Jan 1997 |
| 15 | Cities Service Company | | Oil & Gas Operator | Mar 1983 |
| 16 | Cities Service Oil & Gas Corp | | Oil & Gas Operator | Mar 1988 |
| 17 | Cities Service Oil Co. | | Oil & Gas Operator | Dec 1986 |
| 18 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 19 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 20 | Cochon Properties, LLC | | Oil & Gas Operator | Aug 2016 |
| 21 | Cockrell Oil Corporation | Houston, TX 77002-7348 | Oil & Gas Operator | Feb 2001 |
| 22 | Collet Oil Ventures, Inc. | Denver, CO 80217 | Oil & Gas Operator | Jun 2004 |
| 23 | Columbia Gulf Transmission Co. | | Oil Operator | Dec 2014 |
| 24 | Columbia Gulf Transmission Company, LLC | | Oil Operator | Jul 2024 |
| 25 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 26 | Conquest Exploration Co. | | Oil & Gas Operator | Mar 1992 |
| 27 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Nov 2024 |
| 28 | Corenergy Operating Group, LLC | Houston, TX 77074 | Oil & Gas Operator | Nov 2024 |
| 29 | Crescent DRLG & DVLPMNT, Inc. | | Oil & Gas Operator | Oct 1992 |
| 30 | Crosstex Lig, LLC | | Oil Operator | Mar 2014 |
| 31 | CSL Exploration, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2018 |
| 32 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 33 | Cypress Gas Pipeline Company | | Oil Operator | Dec 1998 |
| 34 | Cypress Gas Pipeline, LLC | | Oil Operator | Sep 2019 |