| 1 | C & B Oil Company | Drumright, OK 74030 | Oil & Gas Operator | May 2025 |
| 2 | C & J Trucks LLC | Seminole, OK 74868-5406 | Oil & Gas Operator | Aug 2025 |
| 3 | C & L Oil And Gas Corporation | Norman, OK 73069-8224 | Oil & Gas Operator | Jun 2025 |
| 4 | C Rose Oil Co. | Midland, TX 79708 | Oil & Gas Operator | Jun 2025 |
| 5 | Cajeza Energy | Drumright, OK 74030 | Oil & Gas Operator | May 2013 |
| 6 | Cal-Tex Operating Co. | Manchaca, TX 78652 | Oil & Gas Operator | May 2020 |
| 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 | Capitol Well Servicing Co., Inc. | Oklahoma City, OK 73143 | Oil & Gas Operator | May 2023 |
| 11 | Capmac Inc | Tulsa, OK 74105-7119 | Oil & Gas Operator | Jan 2007 |
| 12 | Cardinal Oil LLC | Drumright, OK 74030 | Oil & Gas Operator | Apr 2025 |
| 13 | Carmac Energy Corporation | Dallas, TX 75219-2311 | Oil & Gas Operator | Jun 2025 |
| 14 | Casillas Petroleum Corp | Satanta, KS 67870 | Oil & Gas Operator | Jul 2025 |
| 15 | Cason William J | Santee, CA 92071-2765 | Oil Operator | Sep 2019 |
| 16 | Cassidy Jr John | Stroud, OK 74079-0200 | Oil & Gas Operator | Nov 2014 |
| 17 | Castle Exploration Company Inc | Blue Bell, PA 19422 | Oil & Gas Operator | May 2018 |
| 18 | CBL Resources LLC | Tulsa, OK 74136-6308 | Oil & Gas Operator | Jun 2025 |
| 19 | Ceja Corporation | Tulsa, OK 74172 | Oil & Gas Operator | Jul 2025 |
| 20 | Cenergy Exploration Company | Dallas, TX 75231 | Oil & Gas Operator | Sep 2000 |
| 21 | Centrex Operating Company | Tulsa, OK 74105 | Oil & Gas Operator | Jun 2025 |
| 22 | Challenge Operating Inc | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 23 | Cher Oil Company LTD | Ripley, OK 74062 | Oil & Gas Operator | Jun 2025 |
| 24 | Chermac Energy Corporation | Edmond, OK 73083 | Oil & Gas Operator | Apr 2020 |
| 25 | Cherokee Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 26 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Oct 2025 |
| 27 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 28 | Chica Oil Company | Lago VIsta, TX 78645-6561 | Oil & Gas Operator | Mar 2001 |
| 29 | Chisos Exploration Inc | Enid, OK 73703 | Oil & Gas Operator | Dec 2004 |
| 30 | Chizum Oil LLC | Wichita, KS 67211 | Oil & Gas Operator | Jun 2025 |
| 31 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 32 | Circle 9 Resources LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Jun 2025 |
| 33 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Oct 2025 |
| 34 | Cleary Exploration LLC | Oklahoma City, OK 73112-7221 | Oil & Gas Operator | Oct 2014 |
| 35 | Clifton & Associates Inc | Tulsa, OK 74133 | Oil & Gas Operator | May 2020 |
| 36 | CMS Energy Inc | Dallas, TX 75287 | Oil & Gas Operator | Jun 2025 |
| 37 | Coalinga Corporation | Houston, TX 77002 | Oil & Gas Operator | May 1999 |
| 38 | Coastal Oils Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2013 |
| 39 | Coleman Production | Stroud, OK 74079-9609 | Oil & Gas Operator | May 2013 |
| 40 | Colorado Gas Compression Inc | Longmont, CO 80501-5868 | Oil & Gas Operator | Aug 2013 |
| 41 | Columbia Production Company | Edmond, OK 73083 | Oil & Gas Operator | May 2020 |
| 42 | Compass Drilling Inc | Enid, OK 73702-5467 | Oil & Gas Operator | Sep 2014 |
| 43 | Compass Resources | Enid, OK 73702 | Oil & Gas Operator | Dec 2007 |
| 44 | Confed Oil Incorporated | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2008 |
| 45 | Conn-Okla Producing Co Inc | | Oil & Gas Operator | Nov 1992 |
| 46 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 47 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 48 | Consolidated Peto Equity LTD | La Crescenta, CA 91214 | Oil & Gas Operator | Dec 1996 |
| 49 | Consolidated Production Inc. | Seminole, OK 74868 | Oil & Gas Operator | Jun 2025 |
| 50 | Consolidated Properties | Tulsa, OK 74129 | Oil & Gas Operator | Jan 2017 |
| 51 | Contango Resources LLC | Andrews, TX 79714 | Oil & Gas Operator | Oct 2025 |
| 52 | Continental Oil & Refining Co | Catoosa, OK 74015-0831 | Oil & Gas Operator | Nov 2024 |
| 53 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 54 | Cooke County Production Company | Shawnee, OK 74801-1800 | Oil & Gas Operator | Jan 2022 |
| 55 | Cooper Mineral Group Inc | Bellaire, TX 77401 | Oil & Gas Operator | Feb 2004 |
| 56 | Corwin, B. V. | Enid, OK 73701 | Oil & Gas Operator | Apr 2017 |
| 57 | Cougar Energy Investment LLC | Spring, TX 77387-7277 | Oil & Gas Operator | Sep 2014 |
| 58 | Covington Oil Company Inc | Nichols Hills, OK 73116 | Oil & Gas Operator | Jun 2025 |
| 59 | Craig Elder Oil And Gas LLC | Edmond, OK 73013 | Oil & Gas Operator | Jun 2025 |
| 60 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 61 | Crown Energy Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Jun 2025 |
| 62 | Crude Resources | Sapulpa, OK 74066 | Oil & Gas Operator | Mar 2008 |
| 63 | Cudd Operating Corp. | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2020 |
| 64 | Culp & Copple Oil Company | Cushing, OK 74023 | Oil & Gas Operator | Jun 2025 |
| 65 | Cumberland Operating Company | Seminole, OK 74868-1258 | Oil & Gas Operator | Mar 2007 |
| 66 | CVR Supply & Trading, LLC | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2024 |
| 67 | CW Investments | Okmulgee, OK 74447-4026 | Oil & Gas Operator | Jun 2025 |