| 1401 | Drilling Consultants, Inc. | | Oil & Gas Operator | Mar 1992 |
| 1402 | Drilling Exploration & Operating Co. Inc. | | Oil & Gas Operator | Dec 2025 |
| 1403 | Drilling, Operg & Explor, Inc. | | Oil & Gas Operator | Feb 1990 |
| 1404 | Drillmar Energy, Inc. | Houston, TX 77079 | Oil & Gas Operator | Nov 2014 |
| 1405 | Drillmar Operating Company | Houston, TX 77019 | Oil & Gas Operator | Jun 2013 |
| 1406 | Drillogix Exploration LLC | Breckenridge, TX 76424 | Oil Operator | Feb 2026 |
| 1407 | Drilmor, Inc. | Midland, TX 79701 | Oil & Gas Operator | Feb 1998 |
| 1408 | Driltrol | | Oil & Gas Operator | Dec 1984 |
| 1409 | Driscoll Jerry J | | Oil Operator | Apr 1994 |
| 1410 | Driscoll Lease O | | Oil Operator | Jul 1988 |
| 1411 | Driscoll Lease Operations, Inc. | Russell, KS 67665 | Oil Operator | Dec 1998 |
| 1412 | Driscoll S.W.D. Inc. | San Antonio, TX 78229 | Oil & Gas Operator | Feb 2026 |
| 1413 | Driscoll, Jerry J Oil Investment Inc | Russell, KS 67665 | Oil Operator | Sep 2025 |
| 1414 | Driver Energy Of Texas | Dallas, TX 75379-5951 | Oil & Gas Operator | Apr 2011 |
| 1415 | DRL Operating In | | Oil Operator | Sep 1986 |
| 1416 | Drmas, LLC | | Oil & Gas Operator | Nov 2024 |
| 1417 | Drop Tine Exploration, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Dec 2019 |
| 1418 | Drover Corporation (The) | Edmond, OK 73034 | Oil & Gas Operator | Aug 1992 |
| 1419 | DRS Exploration Inc. | San Antonio, TX 78209 | Oil & Gas Operator | May 1999 |
| 1420 | Drum Energy Corp | Hobbs, NM 88241 | Oil & Gas Operator | Mar 1996 |
| 1421 | Drum Energy, L.L.C. | | Gas Operator | Dec 2016 |
| 1422 | Drum Oil & Gas, Inc. | Houston, TX 77082 | Oil & Gas Operator | Feb 2026 |
| 1423 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 1424 | Drummond, F F | | Oil Operator | Nov 2025 |
| 1425 | Drumright Well Service Inc | Oilton, OK 74052 | Oil & Gas Operator | Dec 2025 |
| 1426 | Dry Coulee Oil & Gas Company | Oilmont, MT 59466 | Oil Operator | Oct 2003 |
| 1427 | Dry Creek Disposal Company, Inc. | | Oil & Gas Operator | Nov 2021 |
| 1428 | Dry Creek Operating, LLC | Fort Worth, TX 76109 | Oil & Gas Operator | Feb 2026 |
| 1429 | Dry Fork Production Co | Wichita Falls, TX 76301 | Oil Operator | Apr 2003 |
| 1430 | Dry Fork Production Co., LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Feb 2026 |
| 1431 | Dry Hole Producing LLC | Poland, OH 44514 | Oil & Gas Operator | Dec 2024 |
| 1432 | Dry Hole Producing LP | Poland, OH 44514-3631 | Oil & Gas Operator | Dec 2019 |
| 1433 | Dryes Corner LLC | Oklahoma City, OK 73118 | Oil Operator | Jul 2025 |
| 1434 | DSB Energy, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2026 |
| 1435 | DSM Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | May 1996 |
| 1436 | DSR Oil & Gas, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Feb 2026 |
| 1437 | DSTJ Corporation | Montgomery, TX 77316 | Oil & Gas Operator | Mar 2001 |
| 1438 | DSW Production Corp. | Houston, TX 77265 | Oil & Gas Operator | Feb 2026 |
| 1439 | DSX Operating Co. | Amarillo, TX 79105 | Oil & Gas Operator | Mar 2008 |
| 1440 | Dte Gas Resources, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2007 |
| 1441 | Dte Gas Resources, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2014 |
| 1442 | Du Pont Oil Comp | | Oil Operator | May 1984 |
| 1443 | Dual Energy, Inc. | | Oil & Gas Operator | Oct 2022 |
| 1444 | Dual Operating & Production Co | Tulsa, OK 74145-7831 | Oil & Gas Operator | Apr 2020 |
| 1445 | Dual Production Partners, LLC | Nacogdoches, TX 75963 | Oil & Gas Operator | Feb 2026 |
| 1446 | Dual Quiver Oil & Gas Op, LLC | Flower Mound, TX 75027 | Oil & Gas Operator | Feb 2026 |
| 1447 | Duane Exploration Limited | Andover, KS 67002 | Oil Operator | Jul 1996 |
| 1448 | Dubach Gas Company | | Oil Operator | May 2003 |
| 1449 | Dubisz, Richard And Deborah | East Aurora, NY 14052 | Gas Operator | Dec 2024 |
| 1450 | Dublin Petroleum Corporation | Enid, OK 73702-6029 | Oil & Gas Operator | Dec 2025 |
| 1451 | Dubois, Allen | Whitewater, KS 67154 | Oil Operator | May 2000 |
| 1452 | Ducharme Oil, LLC | | Oil & Gas Operator | Jan 2025 |
| 1453 | Duck Bros Dozer & Trucking Inc | Konawa, OK 74849 | Oil & Gas Operator | Dec 2025 |
| 1454 | Duck Creek Energy Inc | Brecksville, OH 44141 | Oil & Gas Operator | Dec 2024 |
| 1455 | Duck Creek Petroleum LLC | Wooster, OH 44691 | Oil & Gas Operator | Dec 2012 |
| 1456 | Duck Oil Company LLC | Konawa, OK 74849 | Oil Operator | Nov 2025 |
| 1457 | Ducky Oil Corporation | Fort Worth, TX 76120 | Oil & Gas Operator | Feb 2026 |
| 1458 | Duco Energy LLC | Tulsa, OK 74145-4514 | Oil & Gas Operator | Mar 2015 |
| 1459 | Ducote Oil Co. | | Oil & Gas Operator | Sep 1997 |
| 1460 | Duderstadt, A. R. | Boling, TX 77420 | Oil & Gas Operator | Feb 2026 |
| 1461 | Dudley Oil Co. | Crane, TX 79731 | Oil & Gas Operator | Jan 2006 |
| 1462 | Dudrey Carl | | Oil & Gas Operator | Feb 1993 |
| 1463 | Duer Wagner & Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1998 |
| 1464 | Duer Wagoner Com | | Gas Operator | Sep 1988 |
| 1465 | Duerfeldt | | Oil Operator | Dec 2024 |
| 1466 | Duff Oil Co | | Oil & Gas Operator | Aug 2000 |
| 1467 | Duffer William R | Edmond, OK 73034-6761 | Oil & Gas Operator | Aug 2018 |
| 1468 | Dugan Evan | Martinsburg, OH 43037 | Oil & Gas Operator | Dec 2024 |
| 1469 | Dugan Guy E | Walhonding, OH 43843 | Oil & Gas Operator | Dec 2015 |
| 1470 | Dugan Harry Oil Co | Newark, OH 43055 | Oil & Gas Operator | Dec 1993 |
| 1471 | Dugan Oil And Gas LLC | Walhonding, OH 43843-9612 | Oil & Gas Operator | Dec 2024 |
| 1472 | Dugan Production Corp | Farmington, NM 87499 | Oil & Gas Operator | Dec 2025 |
| 1473 | Duggan Stephen F | Boston, MA 2131 | Oil & Gas Operator | Jun 2010 |
| 1474 | Dugger, Glenn | Alice, TX 78332 | Oil & Gas Operator | Nov 2013 |
| 1475 | Duhring Resource Co | Sheffield, PA 16347-2642 | Oil & Gas Operator | Dec 2012 |
| 1476 | Duink, Darryl | Hamburg, NY 14075 | Gas Operator | Dec 2024 |
| 1477 | Duke Drilling Co | Wichita, KS 67202 | Oil & Gas Operator | Feb 2006 |
| 1478 | Duke Energy Field Services Inc | | Oil Operator | Mar 2000 |
| 1479 | Duke Energy Field Services LLC | | Oil Operator | Dec 2006 |
| 1480 | Duke Gas Company LLC | | Oil & Gas Operator | Dec 2025 |
| 1481 | Duke Oil & Gas Company, LLC | Wellsville, KS 66092 | Oil Operator | Sep 2025 |
| 1482 | Duke Oil & Gas Inc | Colorado City, TX 79512 | Oil & Gas Operator | May 2003 |
| 1483 | Duke Oil LLC | Garnett, KS 66032 | Oil Operator | Sep 2025 |
| 1484 | Duke Operating Company | Graham, TX 76450 | Oil Operator | Feb 2026 |
| 1485 | Duke, Hanes Partnership | San Clemente, CA 92672 | Gas Operator | Oct 2004 |
| 1486 | Duke, M. L. | Snyder, TX 79549 | Oil & Gas Operator | Mar 2008 |
| 1487 | Duke, M.A. "Andy", Jr. | Montague, TX 76251 | Oil & Gas Operator | Jun 2023 |
| 1488 | Dukes T F | | Oil & Gas Operator | Apr 2007 |
| 1489 | Dula Energy, Inc. | | Oil & Gas Operator | Sep 2002 |
| 1490 | Dula Production, LLC | Stockdale, TX 78160 | Oil Operator | Feb 2026 |
| 1491 | Dunamis Energy Operating LLC | | Oil & Gas Operator | Nov 2025 |
| 1492 | Dunbar & Son Oil | | Oil & Gas Operator | Oct 1988 |
| 1493 | Dunbar, Ron, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jan 2012 |
| 1494 | Duncan Drilling Co. | Big Spring, TX 79721 | Oil & Gas Operator | Feb 2026 |
| 1495 | Duncan Energy Company | Denver, CO 80202 | Oil & Gas Operator | Mar 2008 |
| 1496 | Duncan Energy Companyuncan Energy Company | Denver, CO 80210 | Oil & Gas Operator | Jun 1995 |
| 1497 | Duncan Energy Inc | | Oil & Gas Operator | Mar 2014 |
| 1498 | Duncan Energy LLC | Dallas, TX 75231 | Oil & Gas Operator | Feb 2026 |
| 1499 | Duncan Jr J Walter | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2016 |
| 1500 | Duncan Land & Exploration, Inc. | Graham, TX 76450 | Oil & Gas Operator | Feb 2026 |