| 1 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 2 | Davco Productions Inc | Springer, OK 73458-8191 | Oil & Gas Operator | Jun 2021 |
| 3 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Feb 2025 |
| 4 | Deaton, Gary L. Corporation | Oklahoma City, OK 73105 | Oil & Gas Operator | Mar 2015 |
| 5 | Dette Oil Corporation | Oklahoma City, OK 73162-6249 | Oil & Gas Operator | Oct 2015 |
| 6 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 7 | Di Energy Inc. | Houston, TX 77067 | Oil & Gas Operator | Jan 2004 |
| 8 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Jun 2025 |
| 9 | DLB Energy Corporation | Oklahoma City, OK 73118-1401 | Oil & Gas Operator | Dec 2014 |
| 10 | Dominion Exp Midcontinent Inc | Oklahoma City, OK 73134-2616 | Oil & Gas Operator | Oct 2024 |
| 11 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 12 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 13 | Douglass Dietz & Daley Inc | Oklahoma City, OK 73154-0125 | Oil & Gas Operator | Aug 2023 |
| 14 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |
| 15 | Duncan Ronald R | Okemah, OK 74859-9603 | Oil & Gas Operator | Aug 2023 |
| 16 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |