| 401 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | Jul 2025 |
| 402 | North American Drilling Corp | Plano, TX 75093 | Oil & Gas Operator | Jul 2025 |
| 403 | North American Royalties, Inc. | Chattanooga, TN 37408 | Oil & Gas Operator | Oct 2001 |
| 404 | North Central Casing Pullers,Inc | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 405 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 406 | North Operating Company | Canton, TX 75103 | Oil & Gas Operator | Jul 2025 |
| 407 | Northland Operating Company | Dallas, TX 75240 | Oil & Gas Operator | Apr 2003 |
| 408 | Northstar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 409 | O'Brien, George H. Jr. | Midland, TX 79701 | Oil & Gas Operator | Jun 1994 |
| 410 | O'Ryan Oil And Gas | Odessa, TX 79768 | Oil & Gas Operator | Jul 2025 |
| 411 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 412 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 413 | Oden, Robin H., Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 1994 |
| 414 | Odessa Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 415 | Okla. Magic Circle Energy Corp. | Shawnee, OK 74801 | Oil & Gas Operator | Jul 2004 |
| 416 | Oklahoma Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Aug 2013 |
| 417 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 418 | Omar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2013 |
| 419 | Omimex Petroleum Inc | Fort Worth, TX 76120 | Oil & Gas Operator | Aug 2022 |
| 420 | Osborn Heirs Co | San Antonio, TX 78217 | Oil & Gas Operator | Jun 2025 |
| 421 | Otb Operating, LLC | Stanton, TX 79782 | Oil & Gas Operator | Jul 2025 |
| 422 | Overflow Energy, LLC | Perryton, TX 79070 | Oil & Gas Operator | Jul 2025 |
| 423 | Overton Park Oil & Gas LP | Fort Worth, TX 76109 | Oil & Gas Operator | Jul 2025 |
| 424 | Ovintiv USA Inc. | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 425 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 426 | Oxy USA WTP LP | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 427 | Oxyrock Operating, LLC | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 428 | P & A Operating, Inc. | Houston, TX 77095 | Oil & Gas Operator | Jul 2025 |
| 429 | P1 Energy, LLC | Judson, TX 75660 | Oil & Gas Operator | Jul 2025 |
| 430 | P4 Operating, LLC | Midland, TX 79710 | Oil & Gas Operator | Jul 2025 |
| 431 | Pactola Development Co | Tulsa, OK 74159 | Oil & Gas Operator | Sep 2004 |
| 432 | Palo Petroleum, Inc. | Dallas, TX 75360 | Oil & Gas Operator | Jul 2025 |
| 433 | Parapetroleum | Kerrville, TX 78028 | Oil & Gas Operator | Feb 1997 |
| 434 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 435 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 436 | Parsley Energy Operations, LLC | Irving, TX 75038 | Oil & Gas Operator | Jan 2021 |
| 437 | Patriot Resources, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 438 | Patterson Petroleum LP | Snyder, TX 79550 | Oil & Gas Operator | Mar 2008 |
| 439 | Pbex Operations, LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 440 | Pcore Exploration & Prod II LLC | Golden, CO 80401 | Oil & Gas Operator | Jun 2020 |
| 441 | Pembrook Oil Company | Big Lake, TX 76932 | Oil & Gas Operator | May 1999 |
| 442 | Perenco LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 443 | Permian Legend LLC | San Marcos, TX 78666 | Oil Operator | Jul 2025 |
| 444 | Permian Resources Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 445 | Permian Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 446 | Permian Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2018 |
| 447 | Permian West Corp. | Odessa, TX 79762 | Oil & Gas Operator | Jul 2025 |
| 448 | Petro Plex Oil Co Inc. | Homosassa, FL 34448 | Oil & Gas Operator | Jul 2020 |
| 449 | Petro-Hunt Permian, LLC | Dallas, TX 75201 | Oil & Gas Operator | Jul 2025 |
| 450 | Petro-Raider LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 451 | Petro-Smith Operating LLC | Houston, TX 77010 | Oil & Gas Operator | Jul 2025 |
| 452 | Petrodata Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 453 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 454 | Petroplex Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 455 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 456 | Pharaoh Oil & Gas, Inc. | MC Camey, TX 79752 | Oil & Gas Operator | Jul 2025 |
| 457 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 458 | Phoenix Hydrocarbons Operating | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 459 | Pillar Energy, LLC | Charleston, WV 25312-5987 | Oil & Gas Operator | Dec 2024 |
| 460 | Pinon Petroleum, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Apr 2004 |
| 461 | Pioneer Exploration Company | Houston, TX 77090 | Oil & Gas Operator | May 2025 |
| 462 | Pioneer Exploration, LLC | Houston, TX 77090 | Oil & Gas Operator | May 2025 |
| 463 | Pioneer Exploration, LTD. | Houston, TX 77090 | Oil & Gas Operator | Sep 2008 |
| 464 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 465 | Pitco Investments, LTD. | Scottsdale, AZ 85261 | Oil & Gas Operator | Jan 2013 |
| 466 | Pitts Energy Co. | Midland, TX 79707 | Oil & Gas Operator | Jul 2025 |
| 467 | Plains Marketing, LP | Cushing, OK 74023 | Oil Operator | Jan 2012 |
| 468 | Plains Petroleum Operating Co | Denver, CO 80202 | Oil & Gas Operator | Dec 2014 |
| 469 | Plains Production Inc | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 1995 |
| 470 | Pogo Panhandle 2004, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2017 |
| 471 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 472 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 473 | PPC Operating Company LLC | Houston, TX 77279 | Oil & Gas Operator | Jul 2019 |
| 474 | Prasad, Hari Production Co. | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 475 | Prasad, LTD. | Midland, TX 79701 | Oil & Gas Operator | Sep 2006 |
| 476 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Jul 2025 |
| 477 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Jul 2025 |
| 478 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 479 | Probity Operating, LLC | Midland, TX 79708 | Oil & Gas Operator | Jul 2014 |
| 480 | Prospctv Invstmnt & TRDG Co, LTD | Tulsa, OK 74170 | Oil & Gas Operator | May 2001 |
| 481 | Psi Production, Inc. | Tyler, TX 75702 | Gas Operator | Jan 1994 |
| 482 | PT Petroleum, LLC | Argyle, TX 76226 | Oil & Gas Operator | Oct 2019 |
| 483 | Pure Resources, L.P. | Midland, TX 79701 | Oil & Gas Operator | Mar 2006 |
| 484 | Purvis Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Jul 2025 |
| 485 | Purvis, J. H. | Midland, TX 79702 | Oil & Gas Operator | Dec 1994 |
| 486 | Qualia, C. F. Operating,Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 2013 |
| 487 | Quay Valley, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2007 |
| 488 | Queen Sand Operating Co. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 489 | Questa Oil & Gas Co. | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2015 |
| 490 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 491 | Railroad Commission Of Texas | Austin, TX 78701 | Oil Operator | Dec 2004 |
| 492 | Ram Energy LLC | Tulsa, OK 74152 | Oil & Gas Operator | Apr 2025 |
| 493 | Ram Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2012 |
| 494 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 495 | Rampart Petroleum, Incorporated | Buffalo Gap, TX 79508 | Oil & Gas Operator | Jan 2009 |
| 496 | Ramtex Energy LLC | Tulsa, OK 74114 | Oil & Gas Operator | Jul 2025 |
| 497 | Randa Operating, Inc. | Big Lake, TX 76932 | Oil Operator | Jul 2025 |
| 498 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 499 | Raptor Resources, Inc. | Austin, TX 78701 | Oil & Gas Operator | Jul 2025 |
| 500 | Rasmussen, Tom | San Angelo, TX 76904 | Oil & Gas Operator | Jul 2025 |