| 401 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 402 | Mercury Exploration Co | Fort Worth, TX 76104 | Oil & Gas Operator | Dec 2006 |
| 403 | Mercury Operating, LLC | Dallas, TX 75208 | Oil & Gas Operator | May 2025 |
| 404 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 405 | Merit Oil Company | San Angelo, TX 76901 | Oil & Gas Operator | May 1994 |
| 406 | Mesa Energy, Inc. | Austin, TX 78755 | Oil & Gas Operator | Dec 2013 |
| 407 | Mesa Ridge Holdings LLC | Abilene, TX 79603 | Oil Operator | May 2025 |
| 408 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2025 |
| 409 | Mid-Tex Energy Inc. | Costa Mesa, CA 92626 | Oil & Gas Operator | Jan 1999 |
| 410 | Mid-Tex Resources | Merkel, TX 79536 | Oil & Gas Operator | Feb 2001 |
| 411 | Midland Oil And Gas, Inc. | Midland, TX 79705 | Oil & Gas Operator | May 2025 |
| 412 | Miller, Bob I. | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 413 | Mirando Resource, L.L.C. | Freer, TX 78357 | Oil & Gas Operator | May 2025 |
| 414 | Mist Prod. & Exploration Corp. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 415 | MJM Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 416 | Mna Enterprises LTD. Co. | Hobbs, NM 88242 | Oil & Gas Operator | May 2025 |
| 417 | Momentum Operating Co., Inc. | Albany, TX 76430 | Oil & Gas Operator | May 2025 |
| 418 | Moncrief W A Jr | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 419 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 420 | Morrell, W. R. | Albany, TX 76430 | Oil & Gas Operator | May 2025 |
| 421 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | May 2025 |
| 422 | Morrison DRLG. & Prod. Co., Inc. | Abilene, TX 79606 | Oil & Gas Operator | Nov 2008 |
| 423 | MSN Oil, Inc. | Avoca, TX 79503 | Oil Operator | May 2025 |
| 424 | Muras Energy Inc | Edmond, OK 73013 | Oil & Gas Operator | Feb 2025 |
| 425 | MWJ Producing Company | Midland, TX 79701 | Oil & Gas Operator | Jul 1998 |
| 426 | Natural Energy, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Jul 1997 |
| 427 | Naumann Oil & Gas, Inc. | Austin, TX 78716 | Oil & Gas Operator | May 2025 |
| 428 | NBX Energy, LLC | Wichita Falls, TX 76301 | Oil & Gas Operator | May 2025 |
| 429 | Neal, Jack Engineering, Inc. | Abilene, TX 79603 | Oil & Gas Operator | Feb 2011 |
| 430 | Neatherlin, Earl Inc. | Avoca, TX 79503 | Oil & Gas Operator | May 2025 |
| 431 | Nichols Brothers | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 432 | Nick Oil | Abilene, TX 79601 | Oil & Gas Operator | May 2025 |
| 433 | North American Exploration Co. | Abilene, TX 79602 | Oil & Gas Operator | Apr 1998 |
| 434 | North Lake Resources LLC | Oklahoma City, OK 73132 | Oil & Gas Operator | May 2025 |
| 435 | Nosivad Oil, Inc. | Clyde, TX 79510 | Oil & Gas Operator | May 2025 |
| 436 | Novo Exploration Corporation | Hurst, TX 76053 | Oil & Gas Operator | Jun 2020 |
| 437 | Nupower Energy, LLC | Houston, TX 77058 | Oil & Gas Operator | May 2025 |
| 438 | O Hill Enterprises, Inc. | La Grange, TX 78945 | Oil & Gas Operator | Jan 2014 |
| 439 | O'Ryan Oil And Gas | Odessa, TX 79768 | Oil & Gas Operator | May 2025 |
| 440 | Ohlhausen Oil Company | Abilene, TX 79608 | Oil & Gas Operator | May 2025 |
| 441 | Oilwell Operators, Inc. | Pampa, TX 79066 | Oil & Gas Operator | May 2025 |
| 442 | Oklahoma Ea II, L.L.C. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2004 |
| 443 | Older Than Dirt LLC | Palo Pinto, TX 76484 | Oil & Gas Operator | May 2025 |
| 444 | One Epoch Energy, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 445 | Orland Oil & Gas LLC | FT Lauderdale, FL 33305 | Oil Operator | May 2025 |
| 446 | Overland Operating Company, LLC | Abilene, TX 79601 | Oil Operator | May 2025 |
| 447 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 448 | P & W Well Service Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 449 | P. R. L. Oil Company | Albany, TX 76430 | Oil & Gas Operator | Apr 2008 |
| 450 | P.B. Blue Dot Properties | Wexford, PA 15090 | Oil & Gas Operator | May 2025 |
| 451 | P.I.D. Drilling Inc | Clyde, TX 79510 | Oil & Gas Operator | May 2025 |
| 452 | Pace Petroleum Company | Dallas, TX 75206 | Oil & Gas Operator | May 2025 |
| 453 | Pan Petroleum Corp. | Abilene, TX 79608 | Oil & Gas Operator | Mar 2008 |
| 454 | Panamerican Operating Inc | Dallas, TX 75219 | Oil & Gas Operator | May 2025 |
| 455 | Par Producing Company | Snyder, TX 79550 | Oil & Gas Operator | Jun 2017 |
| 456 | Paragon Corporation | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 457 | Parallel Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Jan 2010 |
| 458 | Pardue Oil | Breckenridge, TX 76424 | Oil & Gas Operator | Sep 2006 |
| 459 | Pardue Oil, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | May 2025 |
| 460 | Parker Oil Company | Abilene, TX 79601 | Oil & Gas Operator | Feb 2024 |
| 461 | Parmer, I. A. | Abilene, TX 79606 | Oil & Gas Operator | Oct 1993 |
| 462 | Paschal Petroleum, Inc. | Dallas, TX 75380 | Oil & Gas Operator | Apr 1994 |
| 463 | Patterson Petroleum LLC | Snyder, TX 79550 | Oil & Gas Operator | Oct 2007 |
| 464 | Patterson Petroleum LP | Snyder, TX 79550 | Oil & Gas Operator | Mar 2008 |
| 465 | Patterson Petroleum, Inc. | Snyder, TX 79550 | Oil & Gas Operator | Feb 2000 |
| 466 | Patton Exploration, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 467 | Patton, E. N. Oil Company, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 468 | Payne Petroleum | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 469 | Perimeter Resource Company | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 470 | Permian Legend LLC | San Marcos, TX 78666 | Oil Operator | May 2025 |
| 471 | Perry Producing Company, Inc. | Ackerly, TX 79713 | Oil & Gas Operator | May 2025 |
| 472 | Petex | Breckenridge, TX 76424 | Oil & Gas Operator | May 2025 |
| 473 | Petro-Beth Oil & Gas, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Mar 2006 |
| 474 | Petro-Hunt, L.L.C. | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 475 | Petrocorp Acquisition Company | Tulsa, OK 74121 | Oil & Gas Operator | Dec 2002 |
| 476 | Petrocorp Incorporated,A TX.Corp | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2005 |
| 477 | Petroleum Land Company | Abilene, TX 79606 | Oil & Gas Operator | May 2000 |
| 478 | Petrosource Energy Corporation | Fort Worth, TX 76112 | Oil & Gas Operator | May 2025 |
| 479 | Petrotex, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Aug 2003 |
| 480 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 481 | Pgi Operating, LLC | Sweetwater, TX 79556 | Oil Operator | May 2025 |
| 482 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Jul 2024 |
| 483 | Pinon Petroleum, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Apr 2004 |
| 484 | Pioneer Exploration Company | Houston, TX 77090 | Oil & Gas Operator | Mar 2025 |
| 485 | Pioneer Exploration, LLC | Houston, TX 77090 | Oil & Gas Operator | Mar 2025 |
| 486 | Pioneer Exploration, LTD. | Houston, TX 77090 | Oil & Gas Operator | Sep 2008 |
| 487 | Pittencrieff America Inc | Abilene, TX 79608 | Oil & Gas Operator | Feb 2003 |
| 488 | Plantation Operating, LLC | Houston, TX 77041 | Oil & Gas Operator | Nov 2011 |
| 489 | Polk Petroleum, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2024 |
| 490 | Pony Express Corporate Trust | Aledo, TX 76008 | Oil & Gas Operator | May 2025 |
| 491 | Powell Properties, Inc. | Los Altos, CA 94024 | Oil & Gas Operator | May 2025 |
| 492 | Power, Scott | Breckenridge, TX 76424 | Oil & Gas Operator | Sep 1997 |
| 493 | Prairie Petroleum, Inc | Plano, TX 75093 | Oil & Gas Operator | May 1999 |
| 494 | Prensorus Energy, LLC | Abilene, TX 79604 | Oil & Gas Operator | May 2025 |
| 495 | Prentice Petroleum, Inc. | Abilene, TX 79605 | Oil & Gas Operator | Sep 1994 |
| 496 | Price, W. H. | Granbury, TX 76048 | Oil & Gas Operator | Jun 2024 |
| 497 | Privateer Energy LLC | Warren, NJ 07059 | Oil Operator | May 2025 |
| 498 | Proco Operating Co., Inc. | Graford, TX 76449 | Oil & Gas Operator | May 2025 |
| 499 | Production Management Associates | Plano, TX 75075 | Oil & Gas Operator | May 2025 |
| 500 | Production Operators Of TX, LLC | Abilene, TX 79605 | Oil & Gas Operator | May 2025 |