| 1 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 2 | D.J.F. Services, Inc. | Holdenville, OK 74848 | Oil & Gas Operator | Jun 2025 |
| 3 | Dale George | Elmore City, OK 73433 | Oil & Gas Operator | Aug 2022 |
| 4 | Dale Jimmy | Davis, OK 73030 | Oil & Gas Operator | Mar 2015 |
| 5 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 6 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 7 | Darrell'S Drilling Inc | Konawa, OK 74849 | Oil Operator | Feb 2025 |
| 8 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Jun 2025 |
| 9 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Feb 2025 |
| 10 | Dean'S Well Servicing Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Feb 2025 |
| 11 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 12 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 13 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 14 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 15 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |
| 16 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 17 | Devon Resources Corporation | Jenks, OK 74037-3525 | Oil & Gas Operator | Feb 2025 |
| 18 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 19 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 20 | Doco Development Corporation | Norman, OK 73072 | Oil & Gas Operator | Mar 2025 |
| 21 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 22 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 23 | Douglass Dietz & Daley Inc | Oklahoma City, OK 73154-0125 | Oil & Gas Operator | Aug 2023 |
| 24 | DRG Energy Inc | Norman, OK 73026-3171 | Oil & Gas Operator | Jan 2025 |
| 25 | Driver Energy Of Texas | Dallas, TX 75379-5951 | Oil & Gas Operator | Apr 2011 |
| 26 | DSM Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | May 1996 |
| 27 | Duncan Oil & Gas Inc | Norman, OK 73072 | Oil & Gas Operator | Sep 2020 |
| 28 | Dune Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jan 1993 |