| 501 | Northbrook Oil & Gas Company | Norman, OK 73070-4916 | Oil & Gas Operator | Jun 2016 |
| 502 | Nye Oil Company | Oklahoma City, OK 73118-1245 | Oil & Gas Operator | Jun 2004 |
| 503 | O G & E | Oklahoma City, OK 73124 | Oil & Gas Operator | Feb 2014 |
| 504 | Oak Hills Drilling & Oper., LLC | Holdenville, OK 74848 | Oil & Gas Operator | May 2013 |
| 505 | Oak Hills Energy Inc | Holdenville, OK 74848-0470 | Oil & Gas Operator | Sep 2014 |
| 506 | Oakland Petroleum Oper Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | May 2026 |
| 507 | Oil Center Operating Inc | Fort Worth, TX 76102-5108 | Oil & Gas Operator | Apr 2014 |
| 508 | Oil Exploration Of America Inc | Sisseton, SD 57262-9503 | Oil & Gas Operator | Jun 2001 |
| 509 | Oil Recovery Systems Inc | Tulsa, OK 74145-4619 | Oil & Gas Operator | Jan 2026 |
| 510 | Oklahoma Basic Economy Corp | Houston, TX 77002-6003 | Oil & Gas Operator | Apr 2020 |
| 511 | Oklahoma Oil & Gas MGMT Inc | Edmond, OK 73083-6786 | Oil & Gas Operator | Jan 2026 |
| 512 | Oklahoma Prime Energy LLC | Ardmore, OK 73401 | Oil Operator | May 2020 |
| 513 | Oktex Operating LLC | Edmond, OK 73013-1961 | Oil & Gas Operator | May 2020 |
| 514 | Old Dominion Oil Corporation | Oklahoma City, OK 73107 | Oil & Gas Operator | Apr 2009 |
| 515 | Oliphant Gertrud | Holdenville, OK 74848-0849 | Oil Operator | Aug 2013 |
| 516 | Oneok Gas Transportation Co | Tulsa, OK 74121-2089 | Oil & Gas Operator | Oct 2014 |
| 517 | Ovintiv Mid-Continent Inc. | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Feb 2026 |
| 518 | P & H Construction Inc | Wewoka, OK 74884 | Oil & Gas Operator | Jun 2024 |
| 519 | P A Energy Inc | Calvin, OK 74531-0248 | Oil & Gas Operator | Apr 2020 |
| 520 | Pacific Enterprise Oil Co USA | Los Angeles, CA 90071-2005 | Oil & Gas Operator | Aug 2012 |
| 521 | Paleo, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | May 2026 |
| 522 | Paloma Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2018 |
| 523 | Paluca Petroleum Inc | Holdenville, OK 74848 | Oil & Gas Operator | Feb 2026 |
| 524 | Pantera Energy Company | Amarillo, TX 79101 | Oil & Gas Operator | May 2026 |
| 525 | Panther Energy Company, LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2022 |
| 526 | Papal Enterprises Inc | Oklahoma City, OK 73154-1555 | Oil & Gas Operator | Apr 2015 |
| 527 | Par Oil Company Inc | Denver, CO 80201 | Oil & Gas Operator | Jun 2003 |
| 528 | Parkinsol Oil Company | Seminole, OK 74868-1648 | Oil & Gas Operator | Oct 2014 |
| 529 | Parks Bill M | Seminole, OK 74818-1648 | Oil & Gas Operator | Apr 2014 |
| 530 | Patterson George E | Ada, OK 74820-1108 | Oil & Gas Operator | Jul 2016 |
| 531 | Pawnee Petroleum Company | Seminole, OK 74868-0951 | Oil & Gas Operator | Feb 2023 |
| 532 | PCL Energy LLC | Seminole, OK 74868 | Oil & Gas Operator | Jan 2026 |
| 533 | Penn VIrginia MC Operating Co LLC | Houston, TX 77084-7213 | Oil & Gas Operator | Sep 2025 |
| 534 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 535 | Peregrine Petroleum Corp | Oklahoma City, OK 73116-7639 | Oil & Gas Operator | May 2020 |
| 536 | Perkins Nova | Atwood, OK 74827-9738 | Oil Operator | Feb 2014 |
| 537 | Petra Petroleum Management LLC | Hotchkiss, CO 81419-0369 | Gas Operator | Sep 2014 |
| 538 | Petro Davis Inc | Oklahoma City, OK 73142-1807 | Oil & Gas Operator | Jan 2013 |
| 539 | Petro Speed Inc | Norman, OK 73069-8116 | Oil & Gas Operator | Mar 2015 |
| 540 | Petro-Met Energy LLC | Edmond, OK 73034-1237 | Oil Operator | Feb 2026 |
| 541 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | May 2026 |
| 542 | Petroquest Oil & Gas LLC | Wewoka, OK 74884 | Oil & Gas Operator | Jan 2026 |
| 543 | Phase III Drilling Inc | Wetumka, OK 74883-0333 | Oil & Gas Operator | Jan 2026 |
| 544 | Phillips Oil Operating Co | Enid, OK 73703-4921 | Oil & Gas Operator | May 2019 |
| 545 | Phoenix Operating Company, Inc. | Shreveport, LA 71161 | Oil & Gas Operator | Mar 2015 |
| 546 | Pices Energy Production Co. | Alva, OK 73717-9512 | Oil & Gas Operator | Apr 2014 |
| 547 | Plainsmen Energy LLC | Enid, OK 73703-5747 | Oil & Gas Operator | Feb 2026 |
| 548 | Pogue Randall | Ada, OK 74821-1547 | Oil & Gas Operator | Apr 2014 |
| 549 | Ponder Oil Producers LLC | Okemah, OK 74859 | Oil & Gas Operator | Sep 2025 |
| 550 | Post Oak Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Jul 2013 |
| 551 | Pound Robert M | Bristow, OK 74010 | Oil & Gas Operator | Sep 2014 |
| 552 | Power Fuel Producers Inc | Keller, TX 76244-1059 | Oil & Gas Operator | Sep 2001 |
| 553 | Prairie Wind Oil LLC | Blackwell, OK 74647-7242 | Oil & Gas Operator | Nov 2025 |
| 554 | Pre-MC Inc | Allen, OK 74825 | Oil & Gas Operator | Jan 2026 |
| 555 | Prentice Benny P | Allen, OK 74825-0247 | Oil & Gas Operator | Feb 2007 |
| 556 | Prentice Bradley L | Allen, OK 74825 | Oil & Gas Operator | Jan 2026 |
| 557 | Prentice Bro Oil Operators | Allen, OK 74825 | Oil & Gas Operator | Apr 2014 |
| 558 | Prentice Ed | Allen, OK 74825 | Oil & Gas Operator | Dec 2025 |
| 559 | Presley Operating LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2026 |
| 560 | Primary Natural Resources Inc. | Tulsa, OK 74136-6351 | Oil & Gas Operator | Mar 2023 |
| 561 | Prime Operating Company | Midland, TX 79705 | Oil & Gas Operator | May 2026 |
| 562 | Primexx Operating Corporation | Dallas, TX 75206 | Oil & Gas Operator | Mar 2024 |
| 563 | Pringle Operating Co. | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2015 |
| 564 | Proctor Dale & Mildred | Wetumka, OK 74883-6272 | Gas Operator | Jan 2026 |
| 565 | Prospect Enterprises Inc | Wetumka, OK 74883-0068 | Oil & Gas Operator | Apr 2004 |
| 566 | Prospective Investment & Trading | Scottsdale, AZ 85261-4190 | Oil & Gas Operator | Jun 2016 |
| 567 | Protege Energy LLC | Tulsa, OK 74135 | Oil & Gas Operator | Jan 2018 |
| 568 | Proven Reserves Management, Inc. | Dallas, TX 75370 | Oil & Gas Operator | Jan 2026 |
| 569 | Pryor VIctor W Jr | Holdenville, OK 74848 | Oil & Gas Operator | Apr 2017 |
| 570 | Pumping Services Inc | Seminole, OK 74868-2421 | Oil & Gas Operator | Jul 2025 |
| 571 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Jan 2026 |
| 572 | Quench Oil & Gas Inc | Plano, TX 75075-2902 | Oil & Gas Operator | Apr 2009 |
| 573 | Questar Explor & Prod Co | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2017 |
| 574 | Quintana Pet Okla Inc | Houston, TX 77002 | Oil & Gas Operator | Jun 1998 |
| 575 | R & B Oil & Gas Inc | Attica, KS 67009 | Oil & Gas Operator | Jan 2026 |
| 576 | R B Energy Inc | Manchester, KY 40962 | Oil & Gas Operator | Jan 2015 |
| 577 | R Baker Oil LLC | Okemah, OK 74859 | Oil & Gas Operator | Jan 2026 |
| 578 | R C Taylor Operating Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2026 |
| 579 | R H S Inc | Ada, OK 74821-1252 | Oil & Gas Operator | Apr 2020 |
| 580 | R J Exploration LLC | Konawa, OK 74849 | Oil & Gas Operator | Feb 2026 |
| 581 | R K R Exploration | Seminole, OK 74868-9754 | Oil & Gas Operator | Mar 2015 |
| 582 | R W Production Company Inc | Ada, OK 74821-2693 | Oil & Gas Operator | Apr 2011 |
| 583 | Ra-Jac LLC | Norman, OK 73069 | Oil & Gas Operator | Feb 2026 |
| 584 | Radford Dale | Konawa, OK 74849 | Oil & Gas Operator | Jan 2026 |
| 585 | Raf Oil Company | Oklahoma City, OK 73120-1944 | Oil & Gas Operator | Jul 2013 |
| 586 | Rainbow Oil & Gas | Pawhuska, OK 74056-0056 | Oil Operator | Oct 2010 |
| 587 | Rainbow Oil & Gas LLC | Coolville, OH 45723 | Oil & Gas Operator | Dec 2024 |
| 588 | Ram Energy LLC | Tulsa, OK 74152 | Oil & Gas Operator | Feb 2026 |
| 589 | Rampage Energy Inc | Bristow, OK 74010-6415 | Oil & Gas Operator | Apr 2020 |
| 590 | Ramsey Property Management LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Jan 2026 |
| 591 | Ramsey Property MGMT Inc | Oklahoma City, OK 73120-1955 | Oil & Gas Operator | Mar 2019 |
| 592 | Randy And Jan Walker Oil Company LLC | Konawa, OK 74849-9333 | Oil & Gas Operator | Feb 2026 |
| 593 | Ranken Energy Corporation | Edmond, OK 73013 | Oil & Gas Operator | Feb 2026 |
| 594 | Raper Brice Oil Company LLC | Yale, OK 74085-6865 | Oil & Gas Operator | Apr 2015 |
| 595 | Ravil Inc | Edmond, OK 73013 | Gas Operator | Nov 1998 |
| 596 | Rayland Operating LLC | Moro, IL 62067 | Oil Operator | Jun 2023 |
| 597 | Red River Oil & Gas Company | Oklahoma City, OK 73132-5120 | Oil & Gas Operator | Mar 2015 |
| 598 | Redbud E & P, Inc. | Giddings, TX 78942 | Oil & Gas Operator | May 2026 |
| 599 | Reed Power Tongs Inc | Seminole, OK 74818 | Oil & Gas Operator | Sep 2025 |
| 600 | Reed Richard L | Shawnee, OK 74802-1462 | Oil Operator | Nov 1993 |