| 501 | Queen Sand Operating Co. | Dallas, TX 75240 | Oil & Gas Operator | Mar 2008 |
| 502 | Questa Oil & Gas Co. | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2015 |
| 503 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 504 | Railroad Commission Of Texas | Austin, TX 78701 | Oil Operator | Dec 2004 |
| 505 | Ram Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2012 |
| 506 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 507 | Rampart Petroleum, Incorporated | Buffalo Gap, TX 79508 | Oil & Gas Operator | Jan 2009 |
| 508 | Ramtex Energy LLC | Tulsa, OK 74114 | Oil & Gas Operator | Sep 2026 |
| 509 | Randa Operating, Inc. | Big Lake, TX 76932 | Oil Operator | Sep 2026 |
| 510 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 511 | Raptor Resources, Inc. | Austin, TX 78701 | Oil & Gas Operator | Sep 2026 |
| 512 | Rasmussen, Tom | San Angelo, TX 76904 | Oil & Gas Operator | Sep 2026 |
| 513 | Rattler Midstream Operating LLC | Midland, TX 79701 | Oil Operator | Sep 2026 |
| 514 | RBJ & Associates, LP | Midland, TX 79707 | Oil Operator | Jan 2020 |
| 515 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 516 | Recovery Operating LP | San Angelo, TX 76904 | Oil & Gas Operator | Sep 2026 |
| 517 | Red Sand Resources LLC | Ada, OK 74821 | Oil Operator | May 2026 |
| 518 | Red Tail Exploration, LLC | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 519 | Red Tank Resources, LLC | Dallas, TX 75379 | Oil & Gas Operator | Sep 2026 |
| 520 | Reddirt Operating, LLC. | Midland, TX 79710 | Oil & Gas Operator | Sep 2026 |
| 521 | Regions Operating, LLC | Midland, TX 79702 | Oil & Gas Operator | May 2024 |
| 522 | Rein Pusher Operating LLC | Brenham, TX 77834 | Oil & Gas Operator | Sep 2026 |
| 523 | Reliance Energy, Inc. | Austin, TX 78746 | Oil & Gas Operator | Sep 2026 |
| 524 | Reliance Operating Company | Midland, TX 79702 | Oil & Gas Operator | Feb 2000 |
| 525 | Remnant Oil Operating, LLC | Midland, TX 79704 | Oil & Gas Operator | Jul 2024 |
| 526 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Sep 2026 |
| 527 | Reverence Operating LLC | Odessa, TX 79768 | Oil & Gas Operator | Sep 2026 |
| 528 | Rex Energy Operating Corp. | State College, PA 16801 | Oil & Gas Operator | Jun 2012 |
| 529 | Rhonda Operating Company | Midland, TX 79710 | Oil & Gas Operator | Aug 2017 |
| 530 | RHR Oil & Gas, LLC | Fort Worth, TX 76107 | Oil Operator | Sep 2026 |
| 531 | Riata Energy, Inc. | Oklahoma City, OK 73101 | Oil & Gas Operator | Nov 2006 |
| 532 | Richman Petroleum Corp. | Grapevine, TX 76051 | Oil & Gas Operator | Jul 2006 |
| 533 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 534 | Ridgeline Resources, LLC | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 535 | Rising Star Energy, L.L.C. | Dallas, TX 75219 | Oil & Gas Operator | Aug 2006 |
| 536 | Rittenhouse Oil & Gas Co. | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 537 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 538 | Robby Kohutek, Inc. | Ballinger, TX 76821 | Oil & Gas Operator | Sep 2026 |
| 539 | Robert C. Brower, LLC | Southlake, TX 76092 | Oil & Gas Operator | Sep 2026 |
| 540 | Roberts & Hammack, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Sep 2026 |
| 541 | Robertson Resources, Inc. | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Sep 2026 |
| 542 | Roc Operating, Inc. | Plano, TX 75093 | Oil & Gas Operator | Oct 2008 |
| 543 | Rock Fish Operating LLC | McKinney, TX 75070 | Oil & Gas Operator | Sep 2026 |
| 544 | Rosewood Resources Inc | Dallas, TX 75201 | Oil & Gas Operator | Sep 2026 |
| 545 | Rover Petroleum Operating, LLC | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2026 |
| 546 | RP Operating, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 547 | RRP Operating LLC | Houston, TX 77046 | Oil & Gas Operator | Sep 2026 |
| 548 | Russell Operating Company, LLC | Big Lake, TX 76932 | Oil Operator | Sep 2026 |
| 549 | Rwa, LLC | Boyd, TX 76023 | Oil & Gas Operator | Sep 2026 |
| 550 | Sable Permian Resources Land,LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2019 |
| 551 | Sable Permian Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2021 |
| 552 | Safemark Oil & Gas, LLC | McKinney, TX 75072 | Oil & Gas Operator | Mar 2026 |
| 553 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Sep 2026 |
| 554 | Saguaro Petroleum, LLC | Eastland, TX 76448 | Oil & Gas Operator | Sep 2026 |
| 555 | Sahara Operating Company | Midland, TX 79704 | Oil & Gas Operator | Sep 2026 |
| 556 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 557 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 558 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2026 |
| 559 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | May 2026 |
| 560 | Sanco Operating Company | Bullard, TX 75757 | Oil & Gas Operator | Sep 2026 |
| 561 | Sanders Oil & Gas, LTD. | Granbury, TX 76048 | Oil & Gas Operator | Aug 2015 |
| 562 | Scythian, LTD. | Midland, TX 79701 | Oil & Gas Operator | Dec 2020 |
| 563 | Seaboard Oil Company | Midland, TX 79710 | Oil & Gas Operator | Mar 2008 |
| 564 | Seaboard Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Sep 2026 |
| 565 | Sem Operating Company LLC | Houston, TX 77042 | Oil & Gas Operator | Sep 2026 |
| 566 | Sha-Jam Operating Corp. | Midland, TX 79701 | Oil & Gas Operator | Jul 2026 |
| 567 | Shackelford,Frank Oil Properties | Midland, TX 79701 | Oil & Gas Operator | Aug 1997 |
| 568 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 569 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | May 2026 |
| 570 | Shirley, B. J. | Lawn, TX 79530 | Oil & Gas Operator | Mar 2008 |
| 571 | Silver Oil & Gas Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Sep 2026 |
| 572 | Simata Energy | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 573 | Simata Energy, LLC | Midland, TX 79708 | Oil & Gas Operator | Sep 2026 |
| 574 | Sinclair Development, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2026 |
| 575 | Sisters Operating Company | Victoria, TX 77904 | Oil & Gas Operator | Nov 2010 |
| 576 | Slant Operating, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Sep 2026 |
| 577 | Sledge, H. G., Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2016 |
| 578 | SMC Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2026 |
| 579 | Smith Pipe Of Abilene | Abilene, TX 79608 | Oil & Gas Operator | Sep 2026 |
| 580 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 581 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 582 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2026 |
| 583 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 584 | Staley Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Jan 2022 |
| 585 | Stallion Energy, Inc. | Houston, TX 77060 | Oil & Gas Operator | Oct 2017 |
| 586 | Stephens, Autry C. | Midland, TX 79701 | Oil & Gas Operator | Mar 2023 |
| 587 | Stewart Producers, Inc. | Mount Vernon, IL 62864 | Oil & Gas Operator | Apr 2026 |
| 588 | Stowe Energy, Inc. | Vernon, TX 76384 | Oil & Gas Operator | Mar 2003 |
| 589 | Stringer Oil & Gas Co., Inc. | San Angelo, TX 76902 | Oil & Gas Operator | Oct 1996 |
| 590 | Summit Exploration, L.L.C. | Tulsa, OK 74119 | Oil & Gas Operator | Mar 2008 |
| 591 | Summit Petroleum LLC | Midland, TX 79705 | Oil & Gas Operator | Sep 2026 |
| 592 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Sep 2026 |
| 593 | Surge Solutions, Inc. | Bandera, TX 78003 | Oil & Gas Operator | Sep 2026 |
| 594 | Synergex Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | May 2026 |
| 595 | T. L. J. Incorporated | Big Lake, TX 76932 | Oil & Gas Operator | Dec 1998 |
| 596 | Tall City Operations LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2016 |
| 597 | Tamarack Petroleum Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 598 | Tandem Energy Corporation | Houston, TX 77056 | Oil & Gas Operator | Sep 2026 |
| 599 | Targa Midstream Services LLC | Tulsa, OK 74103 | Oil Operator | Mar 2023 |
| 600 | Targa Pipeline Mid-Continent LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2018 |