| 1 | C & L Oil And Gas Corporation | Norman, OK 73069-8224 | Oil & Gas Operator | Jun 2025 |
| 2 | C & L Oil Company | Cross Plains, TX 76443 | Oil & Gas Operator | Oct 2025 |
| 3 | C E D LC | Enid, OK 73702-0326 | Oil & Gas Operator | Oct 2021 |
| 4 | C S Petroleum Inc | Norman, OK 73070 | Oil & Gas Operator | Dec 2024 |
| 5 | Callon Petroleum Company | Natchez, MS 39120 | Oil & Gas Operator | Jan 2000 |
| 6 | Camino Natural Resources LLC | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 7 | Canaan Energy Corporation | Oklahoma City, OK 73154-8806 | Oil & Gas Operator | Mar 2015 |
| 8 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Jul 2025 |
| 9 | Capitol Well Servicing Co., Inc. | Oklahoma City, OK 73143 | Oil & Gas Operator | May 2023 |
| 10 | Carlson Petroleum Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 11 | Casillas Petroleum Corp | Satanta, KS 67870 | Oil & Gas Operator | Jul 2025 |
| 12 | Challenge Operating Inc | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 13 | Charter Oak Production Co LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 2025 |
| 14 | Chen K Wendell | Arlington, TX 76016-2555 | Oil & Gas Operator | Mar 2015 |
| 15 | Cherokee Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 16 | Cherokee Royalties & Minerals Inc | Duncan, OK 73533 | Oil & Gas Operator | May 2025 |
| 17 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Oct 2025 |
| 18 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 19 | Chica Oil Company | Lago VIsta, TX 78645-6561 | Oil & Gas Operator | Mar 2001 |
| 20 | Cimarron Petroleum Corporation | Houston, TX 77057-2696 | Oil & Gas Operator | Jun 2025 |
| 21 | Cirrus Production Company | Enid, OK 73702 | Oil & Gas Operator | Jun 2025 |
| 22 | Claremont Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Feb 2017 |
| 23 | Claremont Exploration Inc | Tulsa, OK 74103-4107 | Oil & Gas Operator | Jun 1997 |
| 24 | Clark Operating Services, Inc. | Okmulgee, OK 74447 | Oil & Gas Operator | May 2013 |
| 25 | Coastal Oils Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2013 |
| 26 | Coastal States Gas Prod. Co. | | Oil & Gas Operator | Jun 1996 |
| 27 | Colt Resources Corporation | Billings, MT 59103 | Oil & Gas Operator | Feb 2013 |
| 28 | Columbus Energy Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2008 |
| 29 | Combest A L | Purcell, OK 73080-6829 | Oil & Gas Operator | Aug 2021 |
| 30 | Combined Resources Corporation | Edmond, OK 73083 | Oil & Gas Operator | Oct 2025 |
| 31 | Compadre Drilling & Expl Corp | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2015 |
| 32 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 33 | Concho Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2015 |
| 34 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 35 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 36 | Consolidated Oil & Gas Inc | Wichita, KS 67202 | Oil & Gas Operator | Dec 2012 |
| 37 | Consolidated Peto Equity LTD | La Crescenta, CA 91214 | Oil & Gas Operator | Dec 1996 |
| 38 | Contango Resources LLC | Andrews, TX 79714 | Oil & Gas Operator | Oct 2025 |
| 39 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 40 | Corner Energy LLC | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Mar 2015 |
| 41 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 42 | Cummings Oil Company | Oklahoma City, OK 73112-6113 | Oil & Gas Operator | Jul 2025 |
| 43 | Czar Resources Inc | Houston, TX 77060 | Oil & Gas Operator | Oct 1992 |