| 401 | Double Eagle Exploration Inc | Windthorst, TX 76389 | Oil Operator | Dec 2023 |
| 402 | Double Eagle Oil Co. | Marshall, TX 75670 | Oil & Gas Operator | Jan 2002 |
| 403 | Double Eagle Operating, LLC | Fort Worth, TX 76113 | Oil & Gas Operator | Apr 2024 |
| 404 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Apr 2024 |
| 405 | Double Eight Oil Company LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2024 |
| 406 | Double J Enterprises | Loving, TX 76460 | Oil Operator | Apr 2024 |
| 407 | Double J Operating Company, Inc. | San Antonio, TX 78205 | Oil Operator | Jan 2008 |
| 408 | Double K Production | Graham, TX 76450 | Oil & Gas Operator | Sep 2014 |
| 409 | Double L Operating | Graham, TX 76450 | Oil & Gas Operator | Nov 2018 |
| 410 | Double M Petroproperties, Inc. | Haskell, TX 79521 | Oil & Gas Operator | Apr 2024 |
| 411 | Double Play Oil & Gas | Portland, TX 78374 | Oil & Gas Operator | Dec 2001 |
| 412 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Apr 2024 |
| 413 | Double R Oil Co. | Charlotte, TX 78011 | Oil & Gas Operator | May 2010 |
| 414 | Double S Liberty Energy, Inc. | Texarkana, TX 75501 | Oil & Gas Operator | Apr 2024 |
| 415 | Double S Operating Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2024 |
| 416 | Double U Oil Co. | San Antonio, TX 78217 | Oil & Gas Operator | Feb 1996 |
| 417 | Double U Oil Co., LTD. | San Antonio, TX 78217 | Oil & Gas Operator | May 2000 |
| 418 | Dougherty Properties | Beeville, TX 78104 | Oil & Gas Operator | Jun 1997 |
| 419 | Doughtie Operating Company, LLC | MC Queeney, TX 78123 | Oil & Gas Operator | Mar 2023 |
| 420 | Douglas Investments Inc | Saginaw, TX 76179-0148 | Oil Operator | Jan 2020 |
| 421 | Douglas Petroleum Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2010 |
| 422 | Douglas, Norvel Trust | H SPG NTL PK, AR 71909 | Oil & Gas Operator | Aug 2013 |
| 423 | Dove Creek Energy, Inc. | Fort Worth, TX 76121 | Oil & Gas Operator | Apr 2024 |
| 424 | Dove Drilling, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 1997 |
| 425 | Dove Mineral | Abilene, TX 79601 | Oil & Gas Operator | Dec 2010 |
| 426 | Dowden, T. L. | Henderson, TX 75652 | Oil & Gas Operator | Apr 2024 |
| 427 | Dowell Oil & Gas | Stephenville, TX 76401 | Oil & Gas Operator | Apr 2024 |
| 428 | Down-Hole Pump Service Co., Inc. | Fort Worth, TX 76109 | Oil & Gas Operator | Apr 2024 |
| 429 | Downing, Mark | Devine, TX 78016 | Oil & Gas Operator | Apr 2024 |
| 430 | Downman Jones Oil Operators, Inc | Brookshire, TX 77423 | Oil & Gas Operator | Jan 2007 |
| 431 | DP Permian Operator, LLC | Houston, TX 77024 | Oil & Gas Operator | Apr 2024 |
| 432 | DP Well Works I, LLC | Salt Lake Cty, UT 84103 | Oil & Gas Operator | Apr 2024 |
| 433 | DP2, LLC | Southlake, TX 76092 | Oil & Gas Operator | Apr 2024 |
| 434 | DPMP Energy LLC | Prosper, TX 75078 | Oil & Gas Operator | Dec 2023 |
| 435 | Drachen Oil Company | San Antonio, TX 78258 | Oil & Gas Operator | Apr 2024 |
| 436 | Draco Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 437 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 438 | Dragon Operating, LLC | Tulsa, OK 74137 | Oil Operator | Apr 2024 |
| 439 | Dragoon Oil & Gas Co. | Fort Worth, TX 76147 | Oil & Gas Operator | May 2015 |
| 440 | Drain Oil Co. | Fritch, TX 79036 | Oil & Gas Operator | Jul 2009 |
| 441 | Drain Oil Co. LLC | Fritch, TX 79036 | Oil & Gas Operator | Apr 2024 |
| 442 | Drake Oil & Gas, LLC | Wichita Falls, TX 76308 | Oil Operator | Apr 2024 |
| 443 | Drake Petroleum, LLC | Cypress, TX 77429 | Oil & Gas Operator | Jun 2023 |
| 444 | Dreher, George R. | Midland, TX 79702 | Oil & Gas Operator | Jan 2018 |
| 445 | Drennan Oil L.L.C. | Ballinger, TX 76821 | Oil & Gas Operator | Apr 2024 |
| 446 | Drennan, D. E. | Graham, TX 76450 | Oil & Gas Operator | Dec 2011 |
| 447 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 448 | DRH Properties LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2014 |
| 449 | Driftwood Energy Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | Dec 2022 |
| 450 | Drill Partners Management, LLC | Houston, TX 77056 | Oil & Gas Operator | Nov 2010 |
| 451 | Drillmar Energy, Inc. | Houston, TX 77079 | Oil & Gas Operator | Nov 2014 |
| 452 | Drillmar Operating Company | Houston, TX 77019 | Oil & Gas Operator | Jun 2013 |
| 453 | Drillogix Exploration LLC | Breckenridge, TX 76424 | Oil Operator | Apr 2024 |
| 454 | Drilmor, Inc. | Midland, TX 79701 | Oil & Gas Operator | Feb 1998 |
| 455 | Driscoll S.W.D. Inc. | San Antonio, TX 78229 | Oil & Gas Operator | Apr 2024 |
| 456 | DRS Exploration Inc. | San Antonio, TX 78209 | Oil & Gas Operator | May 1999 |
| 457 | Drum Oil & Gas, Inc. | Houston, TX 77082 | Oil & Gas Operator | Apr 2024 |
| 458 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 459 | Dry Creek Operating, LLC | Fort Worth, TX 76109 | Oil & Gas Operator | Apr 2024 |
| 460 | Dry Fork Production Co | Wichita Falls, TX 76301 | Oil Operator | Apr 2003 |
| 461 | Dry Fork Production Co., LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2024 |
| 462 | DSB Energy, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 2024 |
| 463 | DSM Exploration Inc | Oklahoma City, OK 73154 | Oil & Gas Operator | May 1996 |
| 464 | DSR Oil & Gas, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Apr 2024 |
| 465 | DSTJ Corporation | Montgomery, TX 77316 | Oil & Gas Operator | Mar 2001 |
| 466 | DSW Production Corp. | Houston, TX 77265 | Oil & Gas Operator | Apr 2024 |
| 467 | DSX Operating Co. | Amarillo, TX 79105 | Oil & Gas Operator | Mar 2008 |
| 468 | Dte Gas Resources, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2007 |
| 469 | Dte Gas Resources, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2014 |
| 470 | Dual Production Partners, LLC | Nacogdoches, TX 75963 | Oil & Gas Operator | Apr 2024 |
| 471 | Dual Quiver Oil & Gas Op, LLC | Flower Mound, TX 75027 | Oil & Gas Operator | Apr 2024 |
| 472 | Duck Creek Energy Inc | Brecksville, OH 44141 | Oil & Gas Operator | Dec 2023 |
| 473 | Ducky Oil Corporation | Fort Worth, TX 76120 | Oil & Gas Operator | Apr 2024 |
| 474 | Duderstadt, A. R. | Boling, TX 77420 | Oil & Gas Operator | Apr 2024 |
| 475 | Dudley Oil Co. | Crane, TX 79731 | Oil & Gas Operator | Jan 2006 |
| 476 | Dugan Production Corp | Farmington, NM 87499 | Oil & Gas Operator | Feb 2024 |
| 477 | Dugger, Glenn | Alice, TX 78332 | Oil & Gas Operator | Nov 2013 |
| 478 | Duke Operating Company | Graham, TX 76450 | Oil Operator | Apr 2024 |
| 479 | Duke, M. L. | Snyder, TX 79549 | Oil & Gas Operator | Mar 2008 |
| 480 | Duke, M.A. "Andy", Jr. | Montague, TX 76251 | Oil & Gas Operator | Jun 2023 |
| 481 | Dula Production, LLC | Stockdale, TX 78160 | Oil Operator | Apr 2024 |
| 482 | Dunbar, Ron, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jan 2012 |
| 483 | Duncan Drilling Co. | Big Spring, TX 79721 | Oil & Gas Operator | Apr 2024 |
| 484 | Duncan Energy Company | Denver, CO 80202 | Oil & Gas Operator | Mar 2008 |
| 485 | Duncan Energy LLC | Dallas, TX 75231 | Oil & Gas Operator | Apr 2024 |
| 486 | Duncan Land & Exploration, Inc. | Graham, TX 76450 | Oil & Gas Operator | Apr 2024 |
| 487 | Duncan Oil Company | Holliday, TX 76366 | Oil Operator | Mar 2008 |
| 488 | Duncan Oil Inc | Denver, CO 80210 | Oil & Gas Operator | Jun 2016 |
| 489 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2024 |
| 490 | Dundee Oil & Supply Inc | Tulsa, OK 74101 | Oil & Gas Operator | Apr 2001 |
| 491 | Dundee Petroleum, Inc. | Buffalo Gap, TX 79508 | Oil & Gas Operator | Aug 2003 |
| 492 | Dune Oil And Gas, Inc. | Odessa, TX 79768 | Oil & Gas Operator | Aug 2006 |
| 493 | Dune Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Jun 2016 |
| 494 | Dune Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 1997 |
| 495 | Dunigan Operating Company, Inc. | Austin, TX 78755 | Oil & Gas Operator | Apr 2024 |
| 496 | Dunigan Petroleum, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 497 | Dunlap Exploration, Inc. | Fort Worth, TX 76101 | Oil & Gas Operator | Nov 2016 |
| 498 | Dunlap, Rodge | Olney, TX 76374 | Oil & Gas Operator | Aug 2002 |
| 499 | Dunne Equities Operating Inc | Houston, TX 77057 | Oil & Gas Operator | Aug 2022 |
| 500 | Dunne Equities, Inc. | Wichita, KS 67226 | Oil & Gas Operator | Apr 2014 |