| 1 | D & R Energy | Spencer, WV 25276-0000 | Oil & Gas Operator | Dec 2021 |
| 2 | Dale, David Dba DD Oil Company | Spencer, WV 25276-0406 | Oil & Gas Operator | Dec 2021 |
| 3 | Davisson, Ancil | | Oil & Gas Operator | Oct 2001 |
| 4 | Deem, J. F. Oil & Gas, LLC | Parkersburg, WV 26104 | Oil & Gas Operator | Dec 2021 |
| 5 | Denex Petroleum Corp. | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 6 | Deran Resources, Inc. | Spencer, WV 25276 | Oil & Gas Operator | Dec 2021 |
| 7 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 8 | Diversified Resources, Inc. | Jackson Center, PA 16133 | Oil & Gas Operator | Dec 2020 |
| 9 | Dolphin Energy LLC | Lake Worth, FL 33467 | Oil & Gas Operator | Jun 2025 |
| 10 | Dominion Energy Transmission, Inc. | | Oil & Gas Operator | Dec 2019 |
| 11 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 12 | Dorward Energy Corporation | Saint Petersburg, FL 33701-3255 | Oil & Gas Operator | Dec 2024 |