| 1 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 2 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Oct 2025 |
| 3 | Dalcor Energy LLC | Duncan, OK 73534 | Oil & Gas Operator | Jun 2025 |
| 4 | Dale Jimmy | Davis, OK 73030 | Oil & Gas Operator | Mar 2015 |
| 5 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 6 | Darwin Allen Dba Wil-Mar Operations | Duncan, OK 73534-1566 | Oil & Gas Operator | Oct 2016 |
| 7 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Jul 2025 |
| 8 | Davco Productions Inc | Springer, OK 73458-8191 | Oil & Gas Operator | Jun 2021 |
| 9 | Davon Drilling Company | Oklahoma City, OK 73113-0665 | Oil & Gas Operator | Mar 2015 |
| 10 | Dawson Resources Inc | Franktown, CO 80116 | Oil & Gas Operator | Mar 2015 |
| 11 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 12 | Dby Investments LLC | Lago VIsta, TX 78645-8011 | Oil & Gas Operator | Nov 2016 |
| 13 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 14 | Dean'S Well Servicing Inc | Ratliff City, OK 73481 | Oil & Gas Operator | Jun 2025 |
| 15 | Dehart Company (The) | Ardmore, OK 73402 | Oil & Gas Operator | Jul 2025 |
| 16 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 17 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 18 | Dette Oil Corporation | Oklahoma City, OK 73162-6249 | Oil & Gas Operator | Oct 2015 |
| 19 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 20 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 21 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 22 | Diamond Cross Oil Co LLC | Ponca City, OK 74601-1104 | Oil & Gas Operator | Jun 2025 |
| 23 | Dickerson Dennis | Velma, OK 73491 | Oil Operator | Jun 2025 |
| 24 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 25 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Oct 2025 |
| 26 | DM Petroleum LLC | Duncan, OK 73533 | Oil Operator | Jun 2025 |
| 27 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 28 | Dominion Exp Midcontinent Inc | Oklahoma City, OK 73134-2616 | Oil & Gas Operator | Oct 2024 |
| 29 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 30 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 31 | Dorey Oil Corporation | Healdton, OK 73438-0856 | Oil Operator | Apr 2014 |
| 32 | Dotson Jack M Operating Co | Norman, OK 73072-6649 | Oil Operator | Oct 1993 |
| 33 | Downhole Oil & Gas Tech LLC | Countyline, OK 73152-0027 | Oil Operator | Oct 2009 |
| 34 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 35 | Dunn Energy LLC | Skiatook, OK 74070-4046 | Oil Operator | Sep 2022 |
| 36 | Dyno Energy LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jun 2025 |