| 1 | D & D Energy Inc | Sapulpa, OK 74066-8734 | Oil & Gas Operator | May 2013 |
| 2 | D & N Operating Corp | Belpre, OH 45714-8181 | Oil & Gas Operator | Dec 2019 |
| 3 | D & R Energy | Spencer, WV 25276-0000 | Oil & Gas Operator | Dec 2021 |
| 4 | D W Energy, LLC | Dunbar, WV 25064 | Oil & Gas Operator | Dec 2021 |
| 5 | D. C. Malcolm, Inc. | Charleston, WV 25301 | Oil & Gas Operator | Dec 2021 |
| 6 | D. G. Haney, Inc. | Charleston, WV 25338-3810 | Oil & Gas Operator | Dec 2021 |
| 7 | Dale, David Dba DD Oil Company | Spencer, WV 25276-0406 | Oil & Gas Operator | Dec 2021 |
| 8 | Dart Oil & Gas Corporation | Mason, MI 48854 | Oil & Gas Operator | Jun 2018 |
| 9 | Davco Drilling Co. | | Gas Operator | Dec 2001 |
| 10 | Davisson, Ancil | | Oil & Gas Operator | Oct 2001 |
| 11 | Deem, J. F. Oil & Gas, LLC | Parkersburg, WV 26104 | Oil & Gas Operator | Dec 2021 |
| 12 | Deem, W. A. | Harrisville, WV 26362-7878 | Oil & Gas Operator | Dec 2001 |
| 13 | Deep Ford Gas Company | Charleston, WV 25321-0169 | Gas Operator | Dec 2021 |
| 14 | Denex Petroleum Corp. | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 15 | Deran Resources, Inc. | Spencer, WV 25276 | Oil & Gas Operator | Dec 2021 |
| 16 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 17 | Devonian Gas Production, Inc. | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 18 | Dickey Energy Company | Grafton, WV 26354 | Gas Operator | Dec 2015 |
| 19 | Dils, Sherman III Dba Dils Oil & Gas | | Oil & Gas Operator | Dec 2020 |
| 20 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Apr 2026 |
| 21 | Diversified Resources, Inc. | Jackson Center, PA 16133 | Oil & Gas Operator | Dec 2020 |
| 22 | Dixie Natural Gas Co. | | Oil & Gas Operator | Dec 2002 |
| 23 | Dodd Oil & Gas | Spencer, WV 25276 | Oil & Gas Operator | Dec 2021 |
| 24 | Dodd, C. C., Oil & Gas | | Oil & Gas Operator | Dec 2021 |
| 25 | Dolphin Energy LLC | Lake Worth, FL 33467 | Oil & Gas Operator | Dec 2025 |
| 26 | Dominion Energy Transmission, Inc. | | Oil & Gas Operator | Dec 2019 |
| 27 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 28 | Dorward Energy Corporation | Saint Petersburg, FL 33701-3255 | Oil & Gas Operator | Dec 2024 |
| 29 | Dri Operating Company | West Chester, PA 19382-0000 | Gas Operator | Dec 2008 |
| 30 | Durst Oil & Gas, Inc. | Point Pleasant, WV 25550 | Oil & Gas Operator | Dec 2021 |
| 31 | Dutch Ridge Gas Ventures, LLC | Charleston, WV 25339 | Oil & Gas Operator | Dec 2021 |