| 401 | Pennzenergy Exp. & Prod., L.L.C. | Houston, TX 77210 | Oil & Gas Operator | Mar 2000 |
| 402 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 403 | Peoples Energy Prod.-TX, L.P. | Houston, TX 77002 | Oil & Gas Operator | Sep 2007 |
| 404 | Person, J.S., Inc. | Longview, TX 75606 | Oil & Gas Operator | Apr 2024 |
| 405 | Petro-Chem Operating Company, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2024 |
| 406 | Petro-Hunt, L.L.C. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 407 | Petrogas Energy Services, LLC | Dallas, TX 75214 | Oil Operator | Apr 2024 |
| 408 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 409 | Petrol Industries, Inc. | Shreveport, LA 71137 | Oil & Gas Operator | Jun 2012 |
| 410 | Petroleum Investments, Inc | Shreveport, LA 71101 | Oil & Gas Operator | Dec 1977 |
| 411 | Petroleum Production MGMT., Inc. | Kansas City, MO 64112 | Oil & Gas Operator | Apr 2024 |
| 412 | Petromining, Inc. | Plano, TX 75026 | Oil & Gas Operator | Apr 2024 |
| 413 | Phillips, Jack L. | Gladewater, TX 75647 | Oil & Gas Operator | Dec 1997 |
| 414 | Phillips, Jack L. Co. | Gladewater, TX 75647 | Oil & Gas Operator | Apr 2024 |
| 415 | Pinewood Exploration Inc. | Arlington, TX 76096 | Oil & Gas Operator | Oct 2011 |
| 416 | Pintail Production Co., Inc. | Fort Worth, TX 76132 | Oil & Gas Operator | Apr 2024 |
| 417 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 418 | Plains Marketing LP | Cushing, OK 74023 | Oil & Gas Operator | Dec 2022 |
| 419 | Plains Production Inc | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 1995 |
| 420 | Pmo | Garland, TX 75040 | Oil & Gas Operator | Feb 2018 |
| 421 | Powell, Gene Investments, Inc. | Longview, TX 75608 | Oil & Gas Operator | Apr 2024 |
| 422 | Powerline Energy Corporation | Arlington, TX 76015 | Oil & Gas Operator | Apr 2024 |
| 423 | Prenwell, LLC | Tallahasse, FL 32309 | Oil & Gas Operator | Apr 2024 |
| 424 | Preston Exploration LLC | Spring, TX 77387 | Oil & Gas Operator | Dec 2014 |
| 425 | Pride Exploration, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Aug 2015 |
| 426 | Princess Three Operating, LLC | Henderson, TX 75653 | Oil & Gas Operator | Apr 2024 |
| 427 | Proex Energy Management, L.L.C. | Spring, TX 77386 | Oil & Gas Operator | Apr 2024 |
| 428 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2024 |
| 429 | Quality Petroleum, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Dec 2021 |
| 430 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Jan 2024 |
| 431 | Quatros Operating Company | Kilgore, TX 75663 | Oil Operator | Apr 2024 |
| 432 | R & C Petroleum, Inc. | Flint, TX 75762 | Oil & Gas Operator | Apr 2024 |
| 433 | R. Pannell Oil Company | Kilgore, TX 75663 | Oil Operator | Jan 2024 |
| 434 | Rainbow Resources, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2007 |
| 435 | Ram Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2012 |
| 436 | Ramtex Energy LLC | Tulsa, OK 74152 | Oil & Gas Operator | Apr 2024 |
| 437 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 438 | Range Production Company, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2024 |
| 439 | RBD-Shelby Agency | Dallas, TX 75283 | Oil & Gas Operator | Dec 1993 |
| 440 | Redstone Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Jan 2020 |
| 441 | Regal Petroleum Services | Euless, TX 76039 | Oil & Gas Operator | Aug 2002 |
| 442 | Reo Operating LLC | Austin, TX 78747 | Oil & Gas Operator | Apr 2024 |
| 443 | Reserve Acquisition Group | Tulsa, OK 74153 | Oil & Gas Operator | Dec 1993 |
| 444 | Reserve Management, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Apr 2024 |
| 445 | Reserve Production, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Mar 2008 |
| 446 | Revilo Exploration, Inc. | Richardson, TX 75081 | Oil & Gas Operator | Jul 2021 |
| 447 | Reynolds Drilling Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Apr 2024 |
| 448 | Rfe Operating, LLC | Tyler, TX 75703 | Oil & Gas Operator | Apr 2024 |
| 449 | Richey Properties, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Apr 2024 |
| 450 | Richey, Ray Management Co., Inc. | Fort Worth, TX 76108 | Oil & Gas Operator | Apr 2024 |
| 451 | Rife Oil Properties Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Apr 2024 |
| 452 | Riverstone Energy Operating, LLC | Houston, TX 77090 | Oil & Gas Operator | Apr 2024 |
| 453 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 454 | Ro-Jo, Inc. | Highland VLG, TX 75077 | Oil & Gas Operator | Aug 2003 |
| 455 | Roach, R. Byron Trustee | Judson, TX 75660 | Oil & Gas Operator | Mar 1999 |
| 456 | Roach, R. Byron, Trustee, LLC | Judson, TX 75660 | Oil & Gas Operator | Mar 2007 |
| 457 | Robbins Petroleum Corp. | Longview, TX 75606 | Oil & Gas Operator | Sep 1994 |
| 458 | Robertson Resources, Inc. | Midland, TX 79708 | Oil & Gas Operator | Apr 2024 |
| 459 | Robinett Resources Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 1999 |
| 460 | Robinson Operating Company | Abilene, TX 79604 | Oil & Gas Operator | Aug 2012 |
| 461 | Roc Operating, Inc. | Plano, TX 75093 | Oil & Gas Operator | Oct 2008 |
| 462 | Rockcliff Energy Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 463 | Rodessa Management, Inc. | Longview, TX 75606 | Oil & Gas Operator | May 1995 |
| 464 | Rojo Burro Petroleo & Gas | Kilgore, TX 75662 | Oil & Gas Operator | Aug 2007 |
| 465 | Roosth Production Co. | Tyler, TX 75711 | Oil & Gas Operator | Apr 2024 |
| 466 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 467 | Rose City Resources, LLC | Tyler, TX 75703 | Oil & Gas Operator | Apr 2024 |
| 468 | Roseland Oil & Gas Inc | Rockwall, TX 75087 | Oil & Gas Operator | Feb 2003 |
| 469 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 470 | Rudman Partnership, The | Dallas, TX 75201 | Oil & Gas Operator | Dec 2014 |
| 471 | Rusk Co. Well Service Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 472 | S M K Energy Corporation | Corpus Chrsti, TX 78475 | Oil & Gas Operator | Apr 2024 |
| 473 | Sabine Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2024 |
| 474 | Sabine Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 475 | Sabine Pipe & Supply Co. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2004 |
| 476 | Sabine Pipe, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 477 | Salvador Oil, LLC | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 478 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 479 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 480 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 481 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2024 |
| 482 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 483 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2024 |
| 484 | Sbog, LLC | Granbury, TX 76048 | Oil & Gas Operator | Feb 2021 |
| 485 | Scana Petroleum Resources Inc | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 486 | Scheriger Production | Graham, TX 76450 | Oil & Gas Operator | Jun 2006 |
| 487 | Scroggins, Bruce E. | Gilmer, TX 75645 | Oil & Gas Operator | Aug 2004 |
| 488 | SDG Operating Company, Inc | Tyler, TX 75701 | Oil & Gas Operator | Apr 2024 |
| 489 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 490 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 491 | Shappell Oil Company, L.L.C. | Kilgore, TX 75663 | Oil Operator | Apr 2024 |
| 492 | Shelby Operating Company | Dallas, TX 75205 | Oil & Gas Operator | Apr 2024 |
| 493 | Shelby Production, Inc. | Kilgore, TX 75663 | Gas Operator | Apr 2024 |
| 494 | Shelby, Michael H. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 1994 |
| 495 | Sheridan Production Co III, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 496 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Jan 2024 |
| 497 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Apr 2024 |
| 498 | Shivers, Linward, Operator | Shreveport, LA 71161 | Oil & Gas Operator | Sep 1997 |
| 499 | Shoco Production, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | May 2020 |
| 500 | Shoshone Oil Company | Dallas, TX 75244 | Oil & Gas Operator | May 1994 |