| 1 | C & B Oil Company | Drumright, OK 74030 | Oil & Gas Operator | Mar 2025 |
| 2 | C & H Oil Company | Ratliff City, OK 73481-0130 | Oil & Gas Operator | Apr 2015 |
| 3 | C & L Oil And Gas Corporation | Norman, OK 73069-8224 | Oil & Gas Operator | Mar 2025 |
| 4 | C B Energy Resources | Bartlesville, OK 74006 | Oil & Gas Operator | Mar 2015 |
| 5 | Calyx Energy III LLC | Tulsa, OK 74136-4226 | Oil & Gas Operator | Feb 2025 |
| 6 | Campbell Production Company | Tulsa, OK 74137-4145 | Oil & Gas Operator | Mar 2015 |
| 7 | Canaan Resources LLC | Oklahoma City, OK 73118-1126 | Gas Operator | Oct 2023 |
| 8 | Canaan Resources X LLC | Oklahoma City, OK 73103-4925 | Oil & Gas Operator | Sep 2024 |
| 9 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Mar 2025 |
| 10 | Capmac Inc | Tulsa, OK 74105-7119 | Oil & Gas Operator | Jan 2007 |
| 11 | Carl E Gungoll Exploration Inc | Oklahoma City, OK 73154-0466 | Oil & Gas Operator | Jan 2016 |
| 12 | Carl E Gungoll Exploration LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2025 |
| 13 | Carlson Petroleum Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 14 | Cates Betty J | Tulsa, OK 74112 | Oil & Gas Operator | Nov 2016 |
| 15 | Cei Petroleum Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Jul 2016 |
| 16 | Centrex Operating Company | Tulsa, OK 74105 | Oil & Gas Operator | Feb 2025 |
| 17 | Cewell Energy LLC | Houston, TX 77042 | Oil & Gas Operator | Jul 2024 |
| 18 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Mar 2025 |
| 19 | Charter Oak Production Co LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2025 |
| 20 | Chesapeake Exploration LLC | Oklahoma City, OK 731540496 | Oil & Gas Operator | Jul 2020 |
| 21 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Jun 2025 |
| 22 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Jun 2025 |
| 23 | Cheyenne Petroleum Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2025 |
| 24 | Chisos Exploration Inc | Enid, OK 73703 | Oil & Gas Operator | Dec 2004 |
| 25 | Choctaw Gas Company | Quinton, OK 74561 | Gas Operator | Feb 2025 |
| 26 | Cimarex Energy Co | Midland, TX 79706 | Oil & Gas Operator | Jun 2025 |
| 27 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Jun 2025 |
| 28 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Jun 2025 |
| 29 | Cities Services Company | | Oil & Gas Operator | Mar 2008 |
| 30 | Citrus Energy Corporation | Castle Rock, CO 80104 | Oil & Gas Operator | Mar 2020 |
| 31 | Cleveland Rod & Tracy | Elmore City, OK 73433-9467 | Oil & Gas Operator | Jul 2023 |
| 32 | Clinton Public Works Authority | Clinton, OK 73601 | Oil & Gas Operator | May 2023 |
| 33 | CM Exploration Company Inc. | | Oil & Gas Operator | Apr 2009 |
| 34 | Coaleum Corporation | Dallas, TX 75205 | Oil & Gas Operator | Jan 2001 |
| 35 | Cola Resources LLC | Houston, TX 77019-5639 | Gas Operator | Nov 2015 |
| 36 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 37 | Concorde Resources Corporation | Eufaula, OK 74432 | Oil & Gas Operator | Feb 2025 |
| 38 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 39 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 40 | Continental Gas Inc | Enid, OK 73702-5103 | Oil & Gas Operator | Apr 2012 |
| 41 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Jun 2025 |
| 42 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Jun 2025 |
| 43 | Cordillera Energy Partners, LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Mar 2020 |
| 44 | Corman, Jack | Dallas, TX 75231 | Oil & Gas Operator | May 2022 |
| 45 | Corterra Energy Operating LLC | Tulsa, OK 74119-4844 | Oil & Gas Operator | Aug 2021 |
| 46 | Cortez Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2016 |
| 47 | County Line Stripper Wells LLC | Chelsea, OK 74016 | Oil & Gas Operator | Feb 2025 |
| 48 | Cove Petroleum Corporation | Shreveport, LA 71101 | Oil & Gas Operator | Jun 2020 |
| 49 | Cox Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2014 |
| 50 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 51 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2025 |
| 52 | Cross Timbers Production Co | Oklahoma City, OK 73102-5605 | Oil & Gas Operator | Mar 2005 |
| 53 | Crow Creek Operating Co III LLC | Tulsa, OK 74137-8432 | Oil & Gas Operator | Apr 2015 |
| 54 | Cyanostar Energy, Inc | Tulsa, OK 74103-4122 | Oil & Gas Operator | Sep 2001 |