| 1 | C & B Oil Company | Drumright, OK 74030 | Oil & Gas Operator | May 2025 |
| 2 | C & L Oil And Gas Corporation | Norman, OK 73069-8224 | Oil & Gas Operator | Jun 2025 |
| 3 | C B Energy Resources | Bartlesville, OK 74006 | Oil & Gas Operator | Mar 2015 |
| 4 | C S Petroleum Inc | Norman, OK 73070 | Oil & Gas Operator | Dec 2024 |
| 5 | Caldwell Engineering & Construction Inc | Chandler, OK 74834-5420 | Oil & Gas Operator | Jan 2025 |
| 6 | Callie Oil Company LLC | Perry, OK 73077 | Oil & Gas Operator | Jun 2025 |
| 7 | Calyx Energy LLC | Tulsa, OK 74146-3807 | Oil & Gas Operator | Feb 2020 |
| 8 | Canaan Energy Corporation | Oklahoma City, OK 73154-8806 | Oil & Gas Operator | Mar 2015 |
| 9 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Jul 2025 |
| 10 | Cardinal Oil LLC | Drumright, OK 74030 | Oil & Gas Operator | Apr 2025 |
| 11 | Casa Grande Exploration Company | Casa Grande, AZ 85194 | Oil & Gas Operator | Jun 2025 |
| 12 | Casillas Petroleum Corp | Satanta, KS 67870 | Oil & Gas Operator | Jul 2025 |
| 13 | Cason William J | Santee, CA 92071-2765 | Oil Operator | Sep 2019 |
| 14 | Cassidy Jr John | Stroud, OK 74079-0200 | Oil & Gas Operator | Nov 2014 |
| 15 | Castle Exploration Company Inc | Blue Bell, PA 19422 | Oil & Gas Operator | May 2018 |
| 16 | Castlerock Resources Inc | Oklahoma City, OK 73116-3710 | Oil & Gas Operator | Jul 2020 |
| 17 | Cbo Oil And Gas LLC | Stillwater, OK 74075-8793 | Oil Operator | Jun 2025 |
| 18 | CDS Oil Company | Tulsa, OK 74147-1514 | Oil & Gas Operator | Mar 2015 |
| 19 | Cei Operating LLC | Katy, TX 77449 | Oil & Gas Operator | Oct 2025 |
| 20 | Challenge Operating Inc | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 21 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 22 | Charter Services LLC | Cushing, OK 74023 | Oil Operator | Jul 2025 |
| 23 | Cher Oil Company LTD | Ripley, OK 74062 | Oil & Gas Operator | Jun 2025 |
| 24 | Cherokee Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 25 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Oct 2025 |
| 26 | Chisholm Oil And Gas Operating LLC | Tulsa, OK 74103-3522 | Oil & Gas Operator | Jul 2025 |
| 27 | Chizum Oil LLC | Wichita, KS 67211 | Oil & Gas Operator | Jun 2025 |
| 28 | Cimarron River Operating Co | Mannford, OK 74044 | Oil & Gas Operator | Jun 2025 |
| 29 | Cimarron Valley Energy Inc | Stillwater, OK 74076 | Oil Operator | Apr 2015 |
| 30 | Circle 9 Resources LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Jun 2025 |
| 31 | Cirrus Production Company | Enid, OK 73702 | Oil & Gas Operator | Jun 2025 |
| 32 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Oct 2025 |
| 33 | Claremont Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Feb 2017 |
| 34 | Claremont Exploration Inc | Tulsa, OK 74103-4107 | Oil & Gas Operator | Jun 1997 |
| 35 | Clay Investments LLC | Stillwater, OK 74075-3600 | Oil & Gas Operator | Jan 2021 |
| 36 | Cloer VIrgil R | Oklahoma City, OK 73121 | Oil & Gas Operator | Apr 1993 |
| 37 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 38 | CMT Operating LLC | Cleveland, OK 74020-0113 | Oil & Gas Operator | Mar 2015 |
| 39 | CMX Inc Of Kansas | Wichita, KS 67206-2561 | Oil & Gas Operator | Jul 2025 |
| 40 | Co-St Oil Operating Co Inc | Enid, OK 73706 | Oil & Gas Operator | Apr 1997 |
| 41 | Coastal Oils Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2013 |
| 42 | Cochran Industrial Corporation | Cushing, OK 74023-1427 | Oil & Gas Operator | Apr 2001 |
| 43 | Colorado Gas Compression Inc | Longmont, CO 80501-5868 | Oil & Gas Operator | Aug 2013 |
| 44 | Colpitt Brothers Oil | Collinsville, OK 74021 | Oil & Gas Operator | Apr 2020 |
| 45 | Colpitt Brothers Operating Co | Collinsville, OK 74021 | Oil & Gas Operator | Jun 2025 |
| 46 | Compass Resources | Enid, OK 73702 | Oil & Gas Operator | Dec 2007 |
| 47 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 48 | Consolidated Peto Equity LTD | La Crescenta, CA 91214 | Oil & Gas Operator | Dec 1996 |
| 49 | Contango Resources LLC | Andrews, TX 79714 | Oil & Gas Operator | Oct 2025 |
| 50 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 51 | Cooper Lisa L | Cushing, OK 74023 | Oil & Gas Operator | Mar 2015 |
| 52 | Cooper Mineral Group Inc | Bellaire, TX 77401 | Oil & Gas Operator | Feb 2004 |
| 53 | Cornelius Petroleum Inc | | Oil & Gas Operator | Jul 2025 |
| 54 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 55 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 56 | Covington Oil Company Inc | Nichols Hills, OK 73116 | Oil & Gas Operator | Jun 2025 |
| 57 | Cox Linda | Bristow, OK 74010-0808 | Oil & Gas Operator | Jan 2018 |
| 58 | Crain & Deisenroth | Tulsa, OK 74103-4433 | Oil & Gas Operator | Mar 2015 |
| 59 | Crain & Deisenroth LLC | Tulsa, OK 74104-6511 | Oil & Gas Operator | Apr 2014 |
| 60 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 61 | Cromer Carroll Oil & Gas LLC | Kalispell, MT 59901 | Oil & Gas Operator | Jun 2025 |
| 62 | Cross Don | Cushing, OK 74023-6316 | Oil & Gas Operator | Feb 2022 |
| 63 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 64 | Cross Timbers Production Co | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 2005 |
| 65 | Crow Creek Operating Co III LLC | Tulsa, OK 74137-8432 | Oil & Gas Operator | Apr 2015 |
| 66 | Crown Energy Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Jun 2025 |
| 67 | Cudd Operating Corp. | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2020 |
| 68 | Culp & Copple Oil Company | Cushing, OK 74023 | Oil & Gas Operator | Jun 2025 |
| 69 | Cundiff Harold | Perkins, OK 74059-4199 | Oil & Gas Operator | Apr 2025 |
| 70 | Cundiff Jack | Perkins, OK 74059-4198 | Oil & Gas Operator | Apr 2014 |