| 1 | D & D Pipe & Equipment Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2005 |
| 2 | D & H Oil Inc | Garber, OK 73738-0657 | Oil & Gas Operator | Apr 2021 |
| 3 | D & J Oil Company | Kermit, TX 79745 | Oil & Gas Operator | Oct 2025 |
| 4 | D & J Oil Company Of Okla Inc | Enid, OK 73706-0129 | Oil & Gas Operator | May 1999 |
| 5 | D & T Swabbing & Well Serv Inc | Hennessey, OK 73742-0124 | Oil & Gas Operator | Jun 2025 |
| 6 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 7 | Dab And Associates Inc | Crescent, OK 73028-0580 | Oil & Gas Operator | Nov 2014 |
| 8 | Dalco Petroleum, Inc | | Oil & Gas Operator | Jan 2006 |
| 9 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 10 | Darden Energy Corp | Hennessey, OK 73742 | Oil & Gas Operator | Jul 1999 |
| 11 | Darnell Bobby J | Oklahoma City, OK 73112-8884 | Oil & Gas Operator | Jul 2025 |
| 12 | Daube Company The | Ardmore, OK 73401 | Oil & Gas Operator | Jul 2025 |
| 13 | Davco Productions Inc | Springer, OK 73458-8191 | Oil & Gas Operator | Jun 2021 |
| 14 | David E Morgan Inc | Danville, CA 94506-2035 | Oil & Gas Operator | Jul 2025 |
| 15 | Davis Operating Company | Elysian Field, TX 75642 | Oil & Gas Operator | Oct 2025 |
| 16 | Davis, William H. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2014 |
| 17 | Dawson Resources Inc | Franktown, CO 80116 | Oil & Gas Operator | Mar 2015 |
| 18 | Dawson-Markwell Exploration Co. | Oklahoma City, OK 73101 | Oil & Gas Operator | Jun 2025 |
| 19 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 20 | Deaton, Gary L. Corporation | Oklahoma City, OK 73105 | Oil & Gas Operator | Mar 2015 |
| 21 | Deck Exploration Inc | Perry, OK 73077-0303 | Oil & Gas Operator | May 2013 |
| 22 | Dedica Energy Corporation | Mattoon, IL 61938 | Oil & Gas Operator | Mar 2008 |
| 23 | Dee-Jay Exploration Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 24 | Deka Exploration Inc | Oklahoma City, OK 73113-0057 | Oil & Gas Operator | Nov 2019 |
| 25 | Deminex U.S. Oil Company | | Oil & Gas Operator | Jan 1998 |
| 26 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 27 | Destin Corporation | Enid, OK 73702-2403 | Oil & Gas Operator | Mar 2005 |
| 28 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 29 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 30 | Diamond A Inc. | Tulsa, OK 74137 | Oil & Gas Operator | Jun 2001 |
| 31 | Diamond Energy Operating Company | Tulsa, OK 74137 | Oil & Gas Operator | Mar 2005 |
| 32 | Diamond Energy, Inc. | Sherman, TX 75091 | Oil & Gas Operator | Oct 2025 |
| 33 | Diamond Production Company LLC | Irving, TX 75016-7853 | Oil & Gas Operator | Jun 2025 |
| 34 | Dinsmore C E | Enid, OK 73702 | Oil & Gas Operator | May 2009 |
| 35 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 36 | Dixie Petroleum Inc | Cashion, OK 73016 | Oil & Gas Operator | May 2001 |
| 37 | DLB Energy Corporation | Oklahoma City, OK 73118-1401 | Oil & Gas Operator | Dec 2014 |
| 38 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Oct 2025 |
| 39 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 40 | Dominion Ok TX E & P Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2018 |
| 41 | Dorado E & P Partners LLC | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2025 |
| 42 | Dorchester Hugoton LTD | Garland, TX 75042-8212 | Oil & Gas Operator | Mar 2004 |
| 43 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 44 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 45 | Drake Exploration Inc | Tulsa, OK 74105-4250 | Oil & Gas Operator | Jul 2025 |
| 46 | Duncan Jr J Walter | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2016 |
| 47 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 48 | Durango Exploration LLC | Oklahoma City, OK 73120-5309 | Oil & Gas Operator | Jul 2025 |
| 49 | Dyco Petroleum Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |