| 601 | Rhodes-Fielding Corporation | Oklahoma City, OK 73134 | Oil & Gas Operator | Mar 2025 |
| 602 | Ric Petroleum, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Aug 2003 |
| 603 | Roberson Oil Company | Houston, TX 77046 | Oil & Gas Operator | Sep 2025 |
| 604 | Robinowitz Oil Company | Tulsa, OK 74136-1429 | Oil & Gas Operator | Feb 2023 |
| 605 | Rocky Top Energy LLC | Bartlesville, OK 74003 | Oil & Gas Operator | Sep 2025 |
| 606 | Rodgers Donald E Jr | Ripley, OK 74062 | Oil & Gas Operator | Mar 2011 |
| 607 | Rodman Petroleum Corp. | Odessa, TX 79768 | Oil & Gas Operator | Jul 2023 |
| 608 | Roe Oil Company | Cushing, OK 74023-0086 | Oil & Gas Operator | Feb 2025 |
| 609 | Rogers Jerry L | Cushing, OK 74023-0911 | Oil & Gas Operator | Mar 2017 |
| 610 | Ronco Energy Resources Inc | Norman, OK 73072 | Oil & Gas Operator | Apr 2015 |
| 611 | Rose Operating Company | Tulsa, OK 74101-2391 | Oil & Gas Operator | Dec 2014 |
| 612 | Royal Oaks Petroleum Corp | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 2001 |
| 613 | Royal Oil & Gas Corp. | Indiana, PA 15701 | Oil & Gas Operator | Apr 2014 |
| 614 | Ruh Oil Company | Collinsville, OK 74021 | Oil & Gas Operator | Aug 2025 |
| 615 | Rush Creek Operating LLC | McKinney, TX 75070 | Oil & Gas Operator | Dec 2025 |
| 616 | S & C Resources Inc | Cleveland, OK 74020 | Oil Operator | May 2025 |
| 617 | S & M Production Inc | Pawnee, OK 74058 | Oil & Gas Operator | Aug 2023 |
| 618 | S & S Oil Company | Electra, TX 76360 | Oil & Gas Operator | Dec 2025 |
| 619 | S T Industries Inc | Drumright, OK 74030 | Oil & Gas Operator | Mar 2011 |
| 620 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2025 |
| 621 | Sand Point Production Inc | Oklahoma City, OK 73172 | Oil & Gas Operator | Aug 2025 |
| 622 | Sand Resources LLC | Norman, OK 73072-4805 | Oil & Gas Operator | Aug 2012 |
| 623 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Dec 2025 |
| 624 | Sanook Inc | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Jan 2007 |
| 625 | Santa Fe Energy Operating Partner LP | Midland, TX 79701 | Oil & Gas Operator | Sep 2004 |
| 626 | Santa Rita Resources Inc & Subs | | Oil & Gas Operator | Mar 2015 |
| 627 | Sasser Company Inc (The) | Perkins, OK 74059 | Oil & Gas Operator | Jul 2025 |
| 628 | Scavenger Oil Company Inc | Englewood, CO 80111 | Oil & Gas Operator | Mar 2000 |
| 629 | Schooley Keith A | Enid, OK 73702-0767 | Oil Operator | May 2006 |
| 630 | Schuler Oil Properties LLC | Cleveland, OK 74020 | Oil Operator | Aug 2025 |
| 631 | Scissortail Energy LLC | Tulsa, OK 74137-3644 | Oil & Gas Operator | Aug 2025 |
| 632 | Seagrove Resources LLC | Malakoff, TX 75148 | Oil & Gas Operator | Aug 2025 |
| 633 | Selco Oil And Gas Inc | Alamo, CA 94507 | Oil & Gas Operator | Sep 2025 |
| 634 | Sellers Jack B Estate Of | Cleveland, OK 74020 | Oil & Gas Operator | Aug 2025 |
| 635 | Sellers Mark A | Drumright, OK 74030 | Oil & Gas Operator | Mar 2020 |
| 636 | Sequoyah Energy Holdings LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Sep 2025 |
| 637 | Service Drilling Co. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 1998 |
| 638 | Service Drilling Co., L.L.C. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 2003 |
| 639 | Settlers Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Nov 2000 |
| 640 | Sevitski & Associates Inc | Pryor, OK 74361 | Oil & Gas Operator | Dec 2000 |
| 641 | Shamrock Well Operations LLC | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Sep 2025 |
| 642 | Shawver & Son Inc | Oklahoma City, OK 73154-0778 | Oil & Gas Operator | Oct 2024 |
| 643 | Shawver Energy Inc | Oklahoma City, OK 73154-0683 | Oil & Gas Operator | Apr 2014 |
| 644 | Shideler Enterprises Inc | Drumright, OK 74030 | Oil & Gas Operator | Feb 2019 |
| 645 | Shields Cooper | Bonita Springs, FL 34135-3421 | Oil & Gas Operator | Jan 2011 |
| 646 | Shields Energy Inc | Fort Smith, AR 72901-4607 | Oil & Gas Operator | Aug 2025 |
| 647 | Shields Operating Inc | Fort Smith, AR 72901-3834 | Oil & Gas Operator | Oct 2021 |
| 648 | Shipman James E Dba Lazy J Oil Co | Hallett, OK 74034 | Oil Operator | Jul 2025 |
| 649 | Short W D Revocable Trust | Oxford, KS 67119-0729 | Oil & Gas Operator | Mar 2015 |
| 650 | Silberman A & M Oil | Oklahoma City, OK 73122-3096 | Oil & Gas Operator | Apr 2014 |
| 651 | Silvertin Farm Production LLC | Tulsa, OK 74137 | Oil & Gas Operator | Apr 2020 |
| 652 | Six "E" Trading Company | Henryetta, OK 74801 | Oil & Gas Operator | Sep 2020 |
| 653 | Smith Mike D | Stillwater, OK 74074 | Oil & Gas Operator | Apr 2015 |
| 654 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 655 | Son Petroleum | Bakersfield, CA 93309 | Oil & Gas Operator | Mar 1994 |
| 656 | Sopac Exploration Inc | Drumright, OK 74030 | Oil & Gas Operator | Jun 1993 |
| 657 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 658 | Southern Star Central Gas Pipeline Inc | Owensboro, KY 42301 | Oil & Gas Operator | May 2025 |
| 659 | Southstar Oil And Gas Inc | Andover, KS 67002-0123 | Oil & Gas Operator | Jul 2020 |
| 660 | Southwest Petroleum Corp | Drumright, OK 74030 | Oil & Gas Operator | Mar 2018 |
| 661 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 662 | Sparks Greg | Afton, OK 74331 | Oil & Gas Operator | Aug 2025 |
| 663 | Sparks Mick Oil Company Inc | Jennings, OK 74038-0250 | Oil & Gas Operator | May 2025 |
| 664 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Sep 2025 |
| 665 | Special Energy Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Dec 2025 |
| 666 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Sep 2025 |
| 667 | Stacy Operating LLC | Cushing, OK 74023 | Oil & Gas Operator | Aug 2025 |
| 668 | Staghorn Resources, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2015 |
| 669 | Statex Petroleum Inc | Dallas, TX 75229 | Oil & Gas Operator | Dec 2000 |
| 670 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Sep 2025 |
| 671 | Still A B Wel-Service Inc | Drumright, OK 74030-0787 | Oil & Gas Operator | Jul 2019 |
| 672 | Still Alex B Estate Of | Sagle, ID 83860-0644 | Oil & Gas Operator | Nov 2018 |
| 673 | Stillwater Oil & Gas | Irving, TX 75062 | Oil & Gas Operator | Mar 2015 |
| 674 | Striker Petroleum Operations LLC | Frisco, TX 75034-2127 | Oil & Gas Operator | Nov 2014 |
| 675 | Sullivan & Co. | Tulsa, OK 74114 | Oil & Gas Operator | May 2022 |
| 676 | Sullivan And Company LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jul 2025 |
| 677 | Supplyco Inc | Perry, OK 73077 | Oil & Gas Operator | Apr 2014 |
| 678 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 679 | T B K Energy Company | Brenham, TX 77833 | Oil & Gas Operator | Aug 2025 |
| 680 | Tag Petroleum Inc | Stillwater, OK 74076 | Oil & Gas Operator | Jan 2021 |
| 681 | Tank Truck'S Inc | Sapulpa, OK 74066 | Oil Operator | Oct 2025 |
| 682 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Sep 2025 |
| 683 | Tarka Energy LLC | Houston, TX 77056-1940 | Oil & Gas Operator | Mar 2022 |
| 684 | Tat, Inc. | Oklahoma City, OK 73127 | Oil & Gas Operator | Feb 2023 |
| 685 | Taylor International Inc | Drumright, OK 74030-1173 | Oil & Gas Operator | Mar 2020 |
| 686 | Taylor R C Companies Inc | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | May 2021 |
| 687 | Tcina Inc | Seminole, OK 74868 | Oil & Gas Operator | May 2023 |
| 688 | Tee Cee'S Inc | Drumright, OK 74030 | Oil & Gas Operator | Sep 2025 |
| 689 | Terry Production Co | Stroud, OK 74079-0475 | Oil & Gas Operator | Aug 2008 |
| 690 | Texaco Exploration & Prod Inc | Houston, TX 77236 | Oil & Gas Operator | Jun 2025 |
| 691 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 692 | Texcel Exploration, Inc. | Colorado SPGS, CO 80960 | Oil & Gas Operator | Dec 2025 |
| 693 | Texocan Minerals Inc | Tulsa, OK 74147 | Oil & Gas Operator | Dec 2000 |
| 694 | The Calvert Company | Oklahoma City, OK 73154-1589 | Oil & Gas Operator | Dec 2021 |
| 695 | Three Sands Oil Inc | Perry, OK 73077 | Oil & Gas Operator | May 2023 |
| 696 | Tilley Oil & Gas, Inc. | Oklahoma City, OK 73172 | Oil & Gas Operator | Dec 2025 |
| 697 | Toklan Oil And Gas Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2025 |
| 698 | Toklan Oil Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2015 |
| 699 | Tony'S Disposal Service Inc | Yale, OK 74085 | Oil Operator | Aug 1997 |
| 700 | Tonys Crude Oil Reclaiming Plant Inc | | Oil Operator | Aug 2025 |