| 1 | Canaan Energy Corporation | Oklahoma City, OK 73154-8806 | Oil & Gas Operator | Mar 2015 |
| 2 | Canok International Inc | Okmulgee, OK 74447 | Oil & Gas Operator | Jul 2025 |
| 3 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Jul 2025 |
| 4 | Canyon Creek Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 5 | Carbon Economy LLC | Chickasha, OK 73023 | Oil & Gas Operator | Jul 2025 |
| 6 | Cates Betty J | Tulsa, OK 74112 | Oil & Gas Operator | Nov 2016 |
| 7 | Chaco Energy Company | Denver, CO 80201 | Oil & Gas Operator | Aug 2025 |
| 8 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 9 | Charter Oak Production Co LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 2025 |
| 10 | Chesapeake Exploration LLC | Oklahoma City, OK 731540496 | Oil & Gas Operator | Jul 2020 |
| 11 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Oct 2025 |
| 12 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 13 | Cheyenne Petroleum Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 2025 |
| 14 | Christeve Oil Company, Inc. | Houston, TX 77068 | Oil & Gas Operator | Dec 2022 |
| 15 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 16 | Cimarron Operating Company | Oklahoma City, OK 73112-3967 | Oil & Gas Operator | May 2011 |
| 17 | Clean Oil LLC | Ada, OK 74820 | Oil & Gas Operator | Jun 2025 |
| 18 | Colt Resources Corporation | Billings, MT 59103 | Oil & Gas Operator | Feb 2013 |
| 19 | Concho Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2015 |
| 20 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 21 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 22 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 23 | Cordillera Energy Partners III LLC | Greenwood VIllage, CO 80111-2856 | Oil & Gas Operator | Mar 2014 |
| 24 | Cordillera Energy Partners LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Mar 2020 |
| 25 | Coterra Energy Operating Co. | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 26 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 27 | Crescendo Resources, L.P. | Amarillo, TX 79188 | Oil & Gas Operator | Jun 2025 |
| 28 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 29 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 30 | Cross Timbers Production Co | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 2005 |
| 31 | Crouch Petroleum Company | Amarillo, TX 79110 | Oil & Gas Operator | Mar 2015 |
| 32 | Crow Oil LLC | Tulsa, OK 74133-2914 | Oil & Gas Operator | Sep 2019 |