| 501 | Pure Resources, L.P. | Midland, TX 79701 | Oil & Gas Operator | Mar 2006 |
| 502 | Purvis Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Nov 2025 |
| 503 | Pyote Disposal Company | Pyote, TX 79777 | Oil Operator | Nov 2025 |
| 504 | Q Natural Resources, LLC | Jones, OK 73049 | Oil & Gas Operator | Nov 2025 |
| 505 | QP, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 506 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Jul 2025 |
| 507 | Quatro Oil And Gas, Inc. | Joshua, TX 76058 | Oil & Gas Operator | Nov 2025 |
| 508 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 509 | R. W. S. Oil Co. | Grandfalls, TX 79742 | Oil & Gas Operator | Nov 2025 |
| 510 | Radius Operating, LLC | Round Rock, TX 78664 | Oil & Gas Operator | Nov 2025 |
| 511 | Raider Oil & Gas Company | MC Camey, TX 79752 | Oil & Gas Operator | Nov 2025 |
| 512 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 513 | Rangeland Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2002 |
| 514 | Rasmussen, Hal J. Operating, Inc | Midland, TX 79701 | Oil & Gas Operator | Apr 2009 |
| 515 | Rasmussen, Tom | San Angelo, TX 76904 | Oil & Gas Operator | Nov 2025 |
| 516 | Rattler Midstream Operating LLC | Midland, TX 79701 | Oil Operator | Nov 2025 |
| 517 | Ray Oil Company | Dallas, TX 75370 | Oil Operator | Dec 1989 |
| 518 | Rayden | Midland, TX 79711 | Oil & Gas Operator | Nov 2025 |
| 519 | RBJ & Associates, LP | Midland, TX 79707 | Oil Operator | Jan 2020 |
| 520 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 521 | Recovery Operating LP | San Angelo, TX 76904 | Oil & Gas Operator | Nov 2025 |
| 522 | Red Oak Energy Co | San Angelo, TX 76906 | Oil & Gas Operator | Nov 2025 |
| 523 | Red Stag Energy, LLC | Ozona, TX 76943 | Oil & Gas Operator | Jan 2022 |
| 524 | Red Stag Operating, LLC | Ozona, TX 76943 | Oil & Gas Operator | Nov 2025 |
| 525 | Red Willow Production, LLC | Ignacio, CO 81137 | Oil & Gas Operator | Oct 2015 |
| 526 | Reeves County Systems, Inc. | Odessa, TX 79760 | Oil & Gas Operator | Aug 2019 |
| 527 | Regent Oil & Gas Company, L.P. | Dallas, TX 75225 | Oil & Gas Operator | Sep 2006 |
| 528 | Rein Pusher Operating LLC | Brenham, TX 77834 | Oil & Gas Operator | Nov 2025 |
| 529 | Remnant Oil Operating, LLC | Midland, TX 79704 | Oil & Gas Operator | Jul 2024 |
| 530 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Nov 2025 |
| 531 | Reo Operating LLC | Austin, TX 78747 | Oil & Gas Operator | Nov 2025 |
| 532 | Resaca Operating Company | Houston, TX 77010 | Oil & Gas Operator | Sep 2013 |
| 533 | Rhombus Operating Co., LTD | Littleton, CO 80160 | Oil & Gas Operator | Jun 2025 |
| 534 | Richardson Operating Company | Denver, CO 80237 | Oil & Gas Operator | Aug 2025 |
| 535 | Richardson, Bud II | Graham, TX 76450 | Oil & Gas Operator | Nov 2025 |
| 536 | Ring Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 537 | Rki Exploration & Production LLC | Tulsa, OK 74172 | Oil & Gas Operator | Nov 2025 |
| 538 | RMB Operating LLC | Lubbock, TX 79493 | Oil & Gas Operator | Nov 2025 |
| 539 | Robertson Resources, Inc. | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Nov 2025 |
| 540 | Roca Operating, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 541 | Roca Resource Company, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 542 | Rodan, Inc. | Wink, TX 79789 | Oil & Gas Operator | Nov 2025 |
| 543 | Rubicon Oil & Gas, LLC | Midland, TX 79701 | Oil & Gas Operator | Nov 2025 |
| 544 | S & S Oil Company | Electra, TX 76360 | Oil & Gas Operator | Nov 2025 |
| 545 | Saber Oil & Gas Ventures, LLC | Midland, TX 79701 | Oil & Gas Operator | Nov 2025 |
| 546 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Nov 2025 |
| 547 | Saga Pet. LTD Liability Co Of Co | Midland, TX 79701 | Oil & Gas Operator | Apr 2004 |
| 548 | Saga Petroleum Corp. | Midland, TX 79701 | Oil & Gas Operator | Mar 2008 |
| 549 | Saga Petroleum LLC Of Colorado | Norman, OK 73072 | Oil & Gas Operator | Nov 2025 |
| 550 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Nov 2025 |
| 551 | Sagebrush Oilandgas Company,LLC | Midland, TX 79701 | Oil & Gas Operator | Mar 2010 |
| 552 | Sahara Operating Company | Midland, TX 79704 | Oil & Gas Operator | Nov 2025 |
| 553 | Samis Oil Company, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Sep 2000 |
| 554 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 555 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 556 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2025 |
| 557 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2025 |
| 558 | Sanco Operating Company | Bullard, TX 75757 | Oil & Gas Operator | Nov 2025 |
| 559 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Nov 2025 |
| 560 | Santa Fe Energy Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 561 | Santa Fe Snyder Corporation | Houston, TX 77024 | Oil & Gas Operator | Oct 2000 |
| 562 | Sapient Energy Corp | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2002 |
| 563 | Satanta Oil Company | Midland, TX 79704 | Oil & Gas Operator | Nov 2025 |
| 564 | SDG Resources L.P. | Montrose, CO 81402 | Oil & Gas Operator | May 2006 |
| 565 | Seaboard Oil Company | Midland, TX 79710 | Oil & Gas Operator | Mar 2008 |
| 566 | Seaboard Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Nov 2025 |
| 567 | Seanard Energy Company | Baton Rouge, LA 70808 | Oil & Gas Operator | Jul 2002 |
| 568 | Sed Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 569 | Seely Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2025 |
| 570 | Shell Western E&P | Houston, TX 77001 | Oil & Gas Operator | Nov 2025 |
| 571 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 572 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Jul 2025 |
| 573 | Siana Oil & Gas | Conroe, TX 77305 | Oil & Gas Operator | Nov 2025 |
| 574 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 575 | Sierra Madre Natural Res., LLC | Dallas, TX 75225 | Oil & Gas Operator | Dec 2016 |
| 576 | Simata Energy | Midland, TX 79708 | Oil & Gas Operator | Nov 2025 |
| 577 | Simata Energy, LLC | Midland, TX 79708 | Oil & Gas Operator | Nov 2025 |
| 578 | Simon, W. D. Oil Co. | Kermit, TX 79745 | Oil & Gas Operator | Nov 2025 |
| 579 | Six-S Properties, Inc. | Austin, TX 78767 | Oil & Gas Operator | Nov 2025 |
| 580 | Slack, R. C. | Pecos, TX 79772 | Oil & Gas Operator | Jul 2000 |
| 581 | SMC Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Nov 2025 |
| 582 | Smith & Marrs Inc. | Lubbock, TX 79424 | Oil & Gas Operator | Apr 2021 |
| 583 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 584 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Nov 2025 |
| 585 | Southwest-Operating | Penwell, TX 79776 | Oil & Gas Operator | Nov 2025 |
| 586 | Space Production Inc. | Monahans, TX 79756 | Oil & Gas Operator | Nov 2025 |
| 587 | Spenergy Corp. | Midland, TX 79701 | Oil & Gas Operator | Dec 1999 |
| 588 | Spindletop Drilling Co. | Dallas, TX 75230 | Oil & Gas Operator | Nov 2025 |
| 589 | Spiral Energy Corp. | Midland, TX 79705 | Oil & Gas Operator | Dec 2019 |
| 590 | Staley Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Jan 2022 |
| 591 | Stanolind Operating Corp. | Midland, TX 79701 | Oil & Gas Operator | Apr 2008 |
| 592 | Stanolind Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2021 |
| 593 | Starrak Operating Company, Inc. | Midland, TX 79706 | Oil & Gas Operator | Jun 1999 |
| 594 | STB Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | Jul 2008 |
| 595 | Stephens, Autry C. | Midland, TX 79701 | Oil & Gas Operator | Mar 2023 |
| 596 | Stevens & Tull, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2000 |
| 597 | Steward Energy, LLC | Frisco, TX 75034 | Oil & Gas Operator | Nov 2014 |
| 598 | Stivers Inc | Graham, TX 76450 | Oil & Gas Operator | May 2003 |
| 599 | Stivers Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Feb 1995 |
| 600 | Stout Energy Inc. | Midland, TX 79708 | Oil & Gas Operator | Nov 2025 |