| 1 | D & J Oil Company | Kermit, TX 79745 | Oil & Gas Operator | Oct 2025 |
| 2 | D & J Oil Company Of Okla Inc | Enid, OK 73706-0129 | Oil & Gas Operator | May 1999 |
| 3 | D & T Swabbing & Well Serv Inc | Hennessey, OK 73742-0124 | Oil & Gas Operator | Jun 2025 |
| 4 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Oct 2025 |
| 5 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 6 | Dar-Lon Operating Company | Lamont, OK 74643 | Oil & Gas Operator | Oct 2000 |
| 7 | Darling Dan Oil | | Oil & Gas Operator | Sep 2018 |
| 8 | Darling Oil Corporation | Lamont, OK 74643 | Oil & Gas Operator | Jul 2025 |
| 9 | Davis Operating Company | Elysian Field, TX 75642 | Oil & Gas Operator | Oct 2025 |
| 10 | Davis, William H. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 11 | Davon Drilling Company | Oklahoma City, OK 73113-0665 | Oil & Gas Operator | Mar 2015 |
| 12 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 13 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 14 | Dem Operations Inc | Lamont, OK 74643-5010 | Oil & Gas Operator | Jul 2025 |
| 15 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 16 | Destin Corporation | Enid, OK 73702-2403 | Oil & Gas Operator | Mar 2005 |
| 17 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 18 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 19 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 20 | Diasu Oil & Gas Co., Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 21 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 22 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 23 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 24 | Drake Exploration Inc | Tulsa, OK 74105-4250 | Oil & Gas Operator | Jul 2025 |
| 25 | DSM Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | May 1996 |
| 26 | Dublin Petroleum Corporation | Enid, OK 73702-6029 | Oil & Gas Operator | Jul 2025 |
| 27 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 28 | Dune Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jan 1993 |
| 29 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |