| 501 | Reach Petroleum | | Oil & Gas Operator | Jan 1994 |
| 502 | Reach Petroleum Corporation | Wichita, KS 67218 | Oil & Gas Operator | Dec 2009 |
| 503 | Read & Stevens, Inc. | Denver, CO 80202 | Oil & Gas Operator | Jul 2023 |
| 504 | Reading & Bates Petroleum | | Oil & Gas Operator | Apr 1989 |
| 505 | Reading & Bates Petroleum Co | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2009 |
| 506 | Ready Oil & Gas | Artesia, NM 882110381 | Oil & Gas Operator | Dec 2007 |
| 507 | Reagan Exploration Company Inc | | Oil & Gas Operator | Nov 1998 |
| 508 | Reagan Production Inc | Terral, OK 73569 | Oil Operator | Sep 2024 |
| 509 | Reagle Production Co. | Snyder, TX 79549 | Oil & Gas Operator | Apr 2004 |
| 510 | Real Production Management LLC | Elmore City, OK 73433 | Oil Operator | Aug 2024 |
| 511 | Realco Oil & Gas, Inc. | | Oil & Gas Operator | Sep 2007 |
| 512 | Reames Jr Keith E | Duncan, OK 73534-0246 | Oil & Gas Operator | Jul 1999 |
| 513 | Reata Petroleum LLC | Independence, KS 67301 | Oil & Gas Operator | Jul 2024 |
| 514 | Reata Resources | Kermit, TX 79745 | Oil & Gas Operator | Sep 2007 |
| 515 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2024 |
| 516 | Reaves Operator | Stephens, AR 71764 | Oil Operator | Apr 2024 |
| 517 | Reb Petroleum Company | Sugar Land, TX 77478 | Oil & Gas Operator | Nov 2024 |
| 518 | Rebco Oil, Inc. | Desdemona, TX 76445 | Oil Operator | Nov 2024 |
| 519 | Rebel Drilling Co. Inc. | | Oil & Gas Operator | Oct 1995 |
| 520 | Rebel Drilling Company, L. P. | | Oil & Gas Operator | Sep 2004 |
| 521 | Rebel Energy, LTD. | Weatherford, TX 76087 | Gas Operator | Nov 2018 |
| 522 | Rebel Enterprises, Inc. | | Oil Operator | Dec 1991 |
| 523 | Rebel Exploration Inc | | Gas Operator | Jul 2015 |
| 524 | Rebel Land And Exploration Inc | | Oil & Gas Operator | Aug 1989 |
| 525 | Rebel Oil Company | Keaton, KY 41226 | Oil & Gas Operator | Jul 2024 |
| 526 | Rebel Oil LLC | | Oil Operator | Jul 2024 |
| 527 | Rebel Oil Of North Louisiana, LLC | | Oil & Gas Operator | Dec 2007 |
| 528 | Rebel Producing, LLC | Spearsville, LA 71277 | Oil & Gas Operator | May 2024 |
| 529 | Rebel Production Company | Kilgore, TX 75663 | Oil Operator | Nov 2024 |
| 530 | Rebel Resources LBC LLC | Sunray, TX 79086 | Gas Operator | Nov 2024 |
| 531 | Rebellion Energy LLC | Tulsa, OK 74135-6241 | Oil & Gas Operator | Jun 2022 |
| 532 | Rebilas, Mark | East Aurora, NY 14052 | Gas Operator | Dec 2023 |
| 533 | Rec Well Service, Inc. | Pleasanton, TX 78064 | Oil & Gas Operator | Jul 2008 |
| 534 | Rec, LLC | Pleasanton, TX 78064 | Oil & Gas Operator | Nov 2024 |
| 535 | Reclusive Energy LLC | Gifford, PA 16732 | Oil & Gas Operator | Dec 2020 |
| 536 | Recoil Resources Operating, Inc. | Houston, TX 77046 | Oil & Gas Operator | Mar 2024 |
| 537 | Recon Oil Co. | Emory, TX 75440 | Oil & Gas Operator | Nov 2024 |
| 538 | Recon Operating, Inc. | | Oil & Gas Operator | Jun 1991 |
| 539 | Recovery Energy Inc | | Oil & Gas Operator | Jan 2014 |
| 540 | Recovery Operating LP | San Angelo, TX 76904 | Oil & Gas Operator | Nov 2024 |
| 541 | Recovery Resourc | | Oil Operator | Dec 1986 |
| 542 | Red Arrow Energy, LLC | Houston, TX 77027 | Oil & Gas Operator | Jul 2016 |
| 543 | Red Bear Drillin | | Oil & Gas Operator | Sep 1992 |
| 544 | Red Bird Producing Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 2023 |
| 545 | Red Bluff Resources Operating LLC | Oklahoma City, OK 73112-5468 | Oil & Gas Operator | Aug 2024 |
| 546 | Red Buck Oil Co. | Copan, OK 74022-0215 | Oil Operator | Nov 2009 |
| 547 | Red Byrd Oil, LLC | Crystal City, TX 78839 | Oil Operator | Nov 2024 |
| 548 | Red Cedar Oil, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Jun 2024 |
| 549 | Red Chalk Resources LLC | Houston, TX 77218 | Oil Operator | Nov 2024 |
| 550 | Red Cloud Exploration Operating LLC | Calabasas, CA 91302 | Oil Operator | Feb 2016 |
| 551 | Red Creek Oil Co | | Oil & Gas Operator | Jun 1995 |
| 552 | Red Dirt Environmental Services LLC | Checotah, OK 74426 | Gas Operator | Aug 2024 |
| 553 | Red Dove Oil & Gas, LLC | Mineral Wells, TX 76067 | Gas Operator | Nov 2024 |
| 554 | Red Eagle Oil Company | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2005 |
| 555 | Red Earth Oil & Gas, Inc. | Oklahoma City, OK 73159 | Oil & Gas Operator | Oct 2021 |
| 556 | Red Fork (USA) Investments Inc | Midland, TX 79710-0272 | Oil & Gas Operator | May 2019 |
| 557 | Red Fork Oil Co | Lakewood, CO 80215 | Oil & Gas Operator | Aug 1993 |
| 558 | Red Fork Oil Production Inc | Mannford, OK 74044-0492 | Oil & Gas Operator | Feb 2017 |
| 559 | Red Fork Production, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Aug 2024 |
| 560 | Red Fork Valley Oil & Gas Co | Cushing, OK 74023 | Oil Operator | Dec 2014 |
| 561 | Red Gap Oil & Gas LLC | Cisco, TX 76437 | Oil & Gas Operator | Nov 2024 |
| 562 | Red Gas Company | Weston, WV 26452-0000 | Oil & Gas Operator | Dec 2021 |
| 563 | Red Hawk Disposal LLC | Oklahoma City, OK 73172 | Oil Operator | Jun 2023 |
| 564 | Red Hawk Petroleum LLC | | Oil & Gas Operator | Aug 2024 |
| 565 | Red Hawk Resources Inc | Edmond, OK 73003-3207 | Oil & Gas Operator | Sep 2024 |
| 566 | Red Hills Energy, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Jul 2024 |
| 567 | Red Hills Resources, Inc. | Englewood, KS 67840 | Oil & Gas Operator | Jul 2024 |
| 568 | Red Horse Petroleum | Dallas, TX 75240 | Oil & Gas Operator | Nov 2024 |
| 569 | Red Jack Oil LLC | | Oil Operator | May 2013 |
| 570 | Red Jacket Energy LLC | Roulette, PA 16746-1408 | Oil & Gas Operator | Dec 2021 |
| 571 | Red Line Company, LTD. | Pampa, TX 79066 | Oil & Gas Operator | Nov 2024 |
| 572 | Red Man Oil, Co. | Albany, TX 76430 | Oil & Gas Operator | Nov 2024 |
| 573 | Red Maple Acres, LLC | Scipio Center, NY 13147 | Gas Operator | Dec 2023 |
| 574 | Red Mesa Holdings/O&G LLC | | Oil & Gas Operator | Nov 2014 |
| 575 | Red Mountain Energy LLC | | Oil & Gas Operator | Sep 2017 |
| 576 | Red Mountain Oil LLC | Golden, CO 80402 | Oil Operator | Nov 1997 |
| 577 | Red Mountain Operating LLC | Oklahoma City, OK 73118-1253 | Oil & Gas Operator | Apr 2024 |
| 578 | Red Mountain Resources LLC | | Oil & Gas Operator | Sep 2023 |
| 579 | Red Oak Energy Co | San Angelo, TX 76906 | Oil & Gas Operator | Nov 2024 |
| 580 | Red Oak Energy LLC | Clarksburg, PA 15725-8824 | Oil & Gas Operator | Dec 2023 |
| 581 | Red Oak Energy, Inc. | Wichita, KS 67207 | Oil & Gas Operator | Jul 2024 |
| 582 | Red Oak Gas Operating Company LP | Houston, TX 77056 | Oil & Gas Operator | Dec 2017 |
| 583 | Red Oak Oil Company, LLC | Spring, TX 77379 | Oil Operator | Nov 2024 |
| 584 | Red Oak Operating, LLC | Magnolia, AR 71753 | Oil & Gas Operator | Jun 2024 |
| 585 | Red Ox Resources LLC | Dumas, TX 79029 | Gas Operator | Sep 2024 |
| 586 | Red Plains Oil & Gas LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Oct 2017 |
| 587 | Red Point Oil | | Oil Operator | May 2019 |
| 588 | Red River Fuels Inc | Bristow, OK 74010-2231 | Oil & Gas Operator | Mar 2008 |
| 589 | Red River Oil & Gas Company | Oklahoma City, OK 73132-5120 | Oil & Gas Operator | Mar 2015 |
| 590 | Red River Oil & Gas Inc. | | Oil & Gas Operator | May 2012 |
| 591 | Red River Oil & Gas LLC | Cherry Hills, CO 80110 | Oil & Gas Operator | Jul 2024 |
| 592 | Red River Oil Corporation | Alvarado, TX 76009-0449 | Oil & Gas Operator | Dec 2016 |
| 593 | Red River Operating & DRLG. Co. | Allen, TX 75002 | Oil & Gas Operator | Nov 2024 |
| 594 | Red River Petroleum Inc | Tipton, OK 73570-0351 | Oil Operator | Aug 2024 |
| 595 | Red River Ranch Holdings LLC | | Gas Operator | Jan 2015 |
| 596 | Red River Services LLC | Tulsa, OK 74136 | Gas Operator | Jan 2007 |
| 597 | Red Rock Energy Group Inc | | Oil & Gas Operator | Jun 2024 |
| 598 | Red Rock Energy L.L.C. | | Oil & Gas Operator | Dec 2021 |
| 599 | Red Rock Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2015 |
| 600 | Red Rock Production L.L.C. | | Oil Operator | Jul 2024 |