| 1 | C. H. C. Gerard | | Oil & Gas Operator | Jul 2024 |
| 2 | C6 Operating, L.L.C. | Keatchie, LA 71046 | Oil & Gas Operator | Nov 2024 |
| 3 | Calpine Natural Gas Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2002 |
| 4 | Calpine Natural Gas Company L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 5 | Calpine Natural Gas L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2006 |
| 6 | Carrollton Resources Corp. | | Oil & Gas Operator | Sep 2000 |
| 7 | Caruthers Producing Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2019 |
| 8 | Centerpoint Energy FLD Ser Inc | | Oil Operator | Feb 2011 |
| 9 | Champlin Petroleum Co. | Rock Springs, WY 82902 | Oil & Gas Operator | Mar 1991 |
| 10 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Jul 2024 |
| 11 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Nov 2024 |
| 12 | Cities Service Oil & Gas Corp | | Oil & Gas Operator | Mar 1988 |
| 13 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 14 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 15 | CMS Oil And Gas Company | Jackson, MI 49201 | Oil & Gas Operator | Oct 2002 |
| 16 | CNG Producing Company | New Orleans, LA 70112 | Oil & Gas Operator | Dec 2015 |
| 17 | Comstock Oil & Gas -- La, Inc. | | Oil & Gas Operator | Mar 2005 |
| 18 | Comstock Oil & Gas--La, LLC | | Oil & Gas Operator | Jun 2024 |
| 19 | Conquest Exploration Co. | | Oil & Gas Operator | Mar 1992 |
| 20 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 21 | Cox Resources Corporation | Dallas, TX 75244 | Oil & Gas Operator | Mar 2015 |
| 22 | Crystal Oil & Land Company | | Oil & Gas Operator | Apr 2002 |
| 23 | CSC Energy Corp. | | Oil & Gas Operator | Dec 2009 |
| 24 | Cypress Operating, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2024 |