| 1 | D & D Services | Cement, OK 73017-9712 | Oil Operator | Feb 2017 |
| 2 | D & J Oil Company | Kermit, TX 79745 | Oil & Gas Operator | Oct 2025 |
| 3 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 4 | Dab Limited | Oklahoma City, OK 73116-9082 | Oil & Gas Operator | Aug 2013 |
| 5 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 6 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 7 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Jul 2025 |
| 8 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 9 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 10 | Dead Horse Oil & Gas LLC | Skiatook, OK 74070-9343 | Oil & Gas Operator | Jun 2015 |
| 11 | Dehart Company (The) | Ardmore, OK 73402 | Oil & Gas Operator | Jul 2025 |
| 12 | Delong, Ralph S | | Oil & Gas Operator | Jun 2025 |
| 13 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 14 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 15 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 16 | Di Energy Inc. | Houston, TX 77067 | Oil & Gas Operator | Jan 2004 |
| 17 | Discovery Natural Resources LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 18 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 19 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Oct 2025 |
| 20 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 21 | Dobson Oil And Gas LLC | Deer Creek, OK 74636 | Oil Operator | Aug 2022 |
| 22 | Doco Development Corporation | Norman, OK 73072 | Oil & Gas Operator | Jun 2025 |
| 23 | Dominion Exp Midcontinent Inc | Oklahoma City, OK 73134-2616 | Oil & Gas Operator | Oct 2024 |
| 24 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 25 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 26 | Donray Petroleum LLC | Choctaw, OK 73020 | Oil & Gas Operator | Jun 2025 |
| 27 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 28 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 29 | Draw Oil & Gas Inc | | Oil & Gas Operator | Jun 1995 |
| 30 | Driver Energy Of Texas | Dallas, TX 75379-5951 | Oil & Gas Operator | Apr 2011 |
| 31 | Duncan Jr J Walter | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2016 |
| 32 | Duncan Oil & Gas Inc | Norman, OK 73072 | Oil & Gas Operator | Sep 2020 |
| 33 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 34 | Dundee Oil & Supply Inc | Tulsa, OK 74101 | Oil & Gas Operator | Apr 2001 |
| 35 | Durango Energy Inc | Chickasha, OK 73023 | Oil Operator | Dec 1999 |
| 36 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |