| 601 | Regal Petroleum Services, Inc. | Euless, TX 76039-1127 | Oil & Gas Operator | May 2015 |
| 602 | Renegade Oil And Gas LLC | Helena, OK 73741-0162 | Oil & Gas Operator | Dec 2019 |
| 603 | Republic Resources Corporation | Oklahoma City, OK 73102-3081 | Oil & Gas Operator | May 2021 |
| 604 | Research Oil Company Inc | Norman, OK 73070-8776 | Oil & Gas Operator | Aug 2019 |
| 605 | Reserve Exploration Co. | Tulsa, OK 74135 | Oil & Gas Operator | Dec 2007 |
| 606 | Reserve Management, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Jun 2026 |
| 607 | Resource Development Inc | Stroud, OK 74079 | Oil & Gas Operator | Feb 2007 |
| 608 | Resource Oil And Gas, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jun 2026 |
| 609 | Resource Operations Inc | Tulsa, OK 74157 | Oil & Gas Operator | May 2016 |
| 610 | Revelation Gas & Oil Oklahoma LLC | Kansas City, KS 66103 | Oil & Gas Operator | Jul 2023 |
| 611 | Revilo Exploration, Inc. | Richardson, TX 75081 | Oil & Gas Operator | Jul 2021 |
| 612 | RF Operating And Supply Inc | | Oil & Gas Operator | Feb 2013 |
| 613 | Rhoades Oil Co | Tulsa, OK 74136-5575 | Oil & Gas Operator | Aug 2013 |
| 614 | Ric Petroleum, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Aug 2003 |
| 615 | Rietz John T & Co Inc | | Oil & Gas Operator | Mar 1992 |
| 616 | Riviera Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2026 |
| 617 | Roberson Oil Company | Houston, TX 77046 | Oil & Gas Operator | Mar 2026 |
| 618 | Robinowitz Oil Company | Tulsa, OK 74136-1429 | Oil & Gas Operator | Feb 2023 |
| 619 | Rockin D Resources LLC | Bristow, OK 74010-4162 | Oil Operator | Feb 2026 |
| 620 | Rocky Top Energy LLC | Bartlesville, OK 74003 | Oil & Gas Operator | Sep 2025 |
| 621 | Roe Oil Company | Cushing, OK 74023-0086 | Oil & Gas Operator | Nov 2025 |
| 622 | Rogers Jerry L | Cushing, OK 74023-0911 | Oil & Gas Operator | Mar 2017 |
| 623 | Romax Corporation | Ardmore, OK 73401-8882 | Oil & Gas Operator | Feb 2022 |
| 624 | Roseland Oil & Gas Inc | Rockwall, TX 75087 | Oil & Gas Operator | Feb 2003 |
| 625 | Rosewood Resources Inc | Dallas, TX 75201 | Oil & Gas Operator | Jun 2026 |
| 626 | Rover Operating, LLC | Chicago, IL 60606 | Oil & Gas Operator | Jan 2026 |
| 627 | Rox Exploration Inc | Norman, OK 73069-6301 | Oil & Gas Operator | Mar 2026 |
| 628 | Royal Oaks Petroleum Corp | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 2001 |
| 629 | S & W Engine Supply | Oklahoma City, OK 73107 | Oil Operator | Jun 2003 |
| 630 | S T Industries Inc | Drumright, OK 74030 | Oil & Gas Operator | Mar 2011 |
| 631 | Sac & Fox Nation | | Oil & Gas Operator | Jul 2025 |
| 632 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2026 |
| 633 | Sand Resources LLC | Norman, OK 73072-4805 | Oil & Gas Operator | Aug 2012 |
| 634 | Sanook Inc | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Jan 2007 |
| 635 | Scissortail Exploration & Production, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Feb 2026 |
| 636 | Seaport Inc | Oklahoma City, OK 73131 | Oil & Gas Operator | Feb 2026 |
| 637 | Sears Joe M | Bethany, OK 730084841 | Oil & Gas Operator | May 2013 |
| 638 | Sec Production Inc | Edmond, OK 73013-3709 | Oil & Gas Operator | Mar 2026 |
| 639 | Selco Oil And Gas Inc | Alamo, CA 94507 | Oil & Gas Operator | Mar 2026 |
| 640 | Sellers Jack B Estate Of | Cleveland, OK 74020 | Oil & Gas Operator | Feb 2026 |
| 641 | Sensor Oil & Gas, Inc. | Duncan, OK 73534 | Oil & Gas Operator | May 2013 |
| 642 | Service Drilling Co. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 1998 |
| 643 | Service Drilling Co., L.L.C. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 2003 |
| 644 | Settlers Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Nov 2000 |
| 645 | Shakespeare Oil Co Inc | Salem, IL 62881 | Oil & Gas Operator | Mar 2026 |
| 646 | Sharber Billy Jack Operating | Konawa, OK 74849-0071 | Oil & Gas Operator | Mar 2015 |
| 647 | Shaver Tommy L | Kingfisher, OK 73750-9612 | Oil & Gas Operator | Apr 2015 |
| 648 | Shelly Energy Inc | Berwyn, PA 19312 | Oil & Gas Operator | Mar 2026 |
| 649 | Shelton Alec & Glenda | Kiefer, OK 74041 | Oil & Gas Operator | Aug 2025 |
| 650 | Sherman Larry Oil Company | Chandler, OK 74834 | Oil & Gas Operator | Mar 2015 |
| 651 | Sherman Oil & Gas Co Inc | Chandler, OK 74834-0571 | Oil & Gas Operator | Apr 2020 |
| 652 | Sherman Oil & Gas, L.L.C. | Chandler, OK 74834 | Oil & Gas Operator | Mar 2026 |
| 653 | Shideler Enterprises Inc | Drumright, OK 74030 | Oil & Gas Operator | Feb 2019 |
| 654 | Shield Operating Co. | Georgetown, TX 78627 | Oil & Gas Operator | Aug 2003 |
| 655 | Shields Well Service Corp | Stroud, OK 74079-3410 | Oil & Gas Operator | Dec 2017 |
| 656 | Shoreline Operating LLC | Oklahoma City, OK 73113 | Oil & Gas Operator | Mar 2026 |
| 657 | Short Oil Co. | Luling, TX 78648 | Oil & Gas Operator | Mar 2026 |
| 658 | Short W D Revocable Trust | Oxford, KS 67119-0729 | Oil & Gas Operator | Mar 2015 |
| 659 | Siegfried R H Inc | Tulsa, OK 74104 | Oil & Gas Operator | Mar 2008 |
| 660 | Signature Exploration Inc. | Shawnee, OK 74804-4130 | Oil & Gas Operator | Mar 2015 |
| 661 | Silberman A & M Oil | Oklahoma City, OK 73122-3096 | Oil & Gas Operator | Apr 2014 |
| 662 | Silvertin Farm Production LLC | Poteau, OK 74953 | Oil & Gas Operator | Apr 2020 |
| 663 | Simco Operating | Shawnee, OK 74804-2501 | Oil Operator | Jan 2013 |
| 664 | Simon Joseph W | Carney, OK 74832-0443 | Oil & Gas Operator | Dec 2016 |
| 665 | Simon Oil Company | Ardmore, OK 73401 | Oil Operator | Feb 2026 |
| 666 | Singer-Fleischaker Oil Op Co | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2002 |
| 667 | Six "E" Trading Company | Henryetta, OK 74801 | Oil & Gas Operator | Sep 2020 |
| 668 | Smith C W & Associates Inc | Oklahoma City, OK 73178-0105 | Oil & Gas Operator | Aug 2013 |
| 669 | Smith Jack Boyd | Elkhart, IN 46515-1968 | Oil & Gas Operator | Oct 2011 |
| 670 | Smith Max Dean | Wewoka, OK 74884 | Oil & Gas Operator | Feb 2026 |
| 671 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jun 2026 |
| 672 | SNR Central Oklahoma Operating LLC | Oklahoma City, OK 73116-7906 | Oil Operator | Mar 2026 |
| 673 | SNR Operating, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Jun 2026 |
| 674 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 675 | Sopac Exploration Inc | Drumright, OK 74030 | Oil & Gas Operator | Jun 1993 |
| 676 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 677 | Southstar Oil And Gas Inc | Andover, KS 67002-0123 | Oil & Gas Operator | Jul 2020 |
| 678 | Southwest Petroleum Corp | Drumright, OK 74030 | Oil & Gas Operator | Mar 2018 |
| 679 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Jun 2026 |
| 680 | Sparks Mick Oil Company Inc | Jennings, OK 74038-0250 | Oil & Gas Operator | Mar 2026 |
| 681 | Sparks Petroleum Company | Oklahoma City, OK 73128 | Oil & Gas Operator | Mar 1998 |
| 682 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Mar 2026 |
| 683 | Special Energy Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Jun 2026 |
| 684 | Speller Oil Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Feb 2026 |
| 685 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Mar 2026 |
| 686 | Spicer Oil Company, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Dec 2008 |
| 687 | Spirit Energy Inc | Edmond, OK 73034 | Oil & Gas Operator | Apr 1999 |
| 688 | Splawn & Splawn | Saint Louis, OK 74866-0098 | Oil & Gas Operator | Mar 2025 |
| 689 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 690 | Stacy Operating LLC | Cushing, OK 74023 | Oil & Gas Operator | Feb 2026 |
| 691 | Stevens & Tull, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2000 |
| 692 | Still A B Wel-Service Inc | Drumright, OK 74030-0787 | Oil & Gas Operator | Jul 2019 |
| 693 | Still Alex B Estate Of | Sagle, ID 83860-0644 | Oil & Gas Operator | Nov 2018 |
| 694 | Stillwater Oil & Gas | Irving, TX 75062 | Oil & Gas Operator | Mar 2015 |
| 695 | Stone Creek Operating, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Jun 2026 |
| 696 | Stover Company | Tulsa, OK 74152-0786 | Oil & Gas Operator | Jan 2013 |
| 697 | STP Cherokee Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2014 |
| 698 | Stroud Oil Properties, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2013 |
| 699 | Sullivan & Co. | Tulsa, OK 74114 | Oil & Gas Operator | May 2022 |
| 700 | Sultex Oil & Gas Inc | Houston, TX 77059-3126 | Oil & Gas Operator | Aug 2002 |