| 1 | D & B Oil Company | Graham, TX 76450 | Oil & Gas Operator | Jun 2025 |
| 2 | D & D Pipe & Equipment Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2005 |
| 3 | D & F Oil Company | Dewey, OK 74029 | Oil & Gas Operator | Apr 2001 |
| 4 | D & M Production Co Inc | Drumright, OK 74030 | Oil & Gas Operator | Jan 2025 |
| 5 | D & S Operating | Texhoma, OK 73949 | Oil & Gas Operator | May 2001 |
| 6 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 7 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Jun 2025 |
| 8 | Dalcor Energy LLC | Duncan, OK 73534 | Oil & Gas Operator | Mar 2025 |
| 9 | Dale George | Elmore City, OK 73433 | Oil & Gas Operator | Aug 2022 |
| 10 | Dale Jimmy | Davis, OK 73030 | Oil & Gas Operator | Mar 2015 |
| 11 | Dales Tank Truck Service Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Feb 2025 |
| 12 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Apr 2025 |
| 13 | Daube Exploration Company | Ardmore, OK 73402 | Oil & Gas Operator | Nov 2020 |
| 14 | Davis & Hamilton Oil Company | Edmond, OK 73083-3670 | Oil Operator | Aug 2022 |
| 15 | Davis Bros. Oil Producers, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Apr 2020 |
| 16 | Davis, William H. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 17 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Jun 2025 |
| 18 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Feb 2025 |
| 19 | Dean'S Well Servicing Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Feb 2025 |
| 20 | Dehart Company (The) | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2025 |
| 21 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 22 | Delta D Operations | Wilson, OK 73463 | Oil & Gas Operator | Jul 2014 |
| 23 | Delta D Operations Inc | Ardmore, OK 73401-8678 | Oil & Gas Operator | Apr 2014 |
| 24 | Dennis Don Oil Company | Grady, OK 73569-9998 | Oil Operator | Jan 2002 |
| 25 | Depco Inc. | Denver, CO 80202 | Oil & Gas Operator | Apr 2014 |
| 26 | Dette Oil Corporation | Oklahoma City, OK 73162-6249 | Oil & Gas Operator | Oct 2015 |
| 27 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 28 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |
| 29 | Dexxon, Inc. | Kiefer, OK 74041 | Oil & Gas Operator | Feb 2025 |
| 30 | Diamondback-Disposal LLC | Oklahoma City, OK 73134-1016 | Oil Operator | Dec 2008 |
| 31 | Dickerson Oil | Ada, OK 74820 | Oil Operator | Jan 2025 |
| 32 | Dimock Petroleum | Dallas, TX 75205 | Oil Operator | Apr 2014 |
| 33 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Jun 2025 |
| 34 | Dobbins Family Residual Trust | Ardmore, OK 73401 | Oil Operator | Jul 2008 |
| 35 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 36 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 37 | Dorey Oil Corporation | Healdton, OK 73438-0856 | Oil Operator | Apr 2014 |
| 38 | Dotson Jack M Operating Co | Norman, OK 73072-6649 | Oil Operator | Oct 1993 |
| 39 | Douglas Oil & Gas Co Inc | Ada, OK 74820 | Oil Operator | Apr 2014 |
| 40 | Dunn Energy LLC | Skiatook, OK 74070-4046 | Oil Operator | Sep 2022 |