| 501 | National Oil Company | Garden City, KS 67846 | Oil & Gas Operator | Jun 2024 |
| 502 | Natural Gas Pipeline Co Of Am LLC | Downers Grove, IL 60515-3708 | Oil & Gas Operator | Mar 2015 |
| 503 | Nbi Services, Inc. | Tulsa, OK 74159 | Oil & Gas Operator | Dec 2025 |
| 504 | Neok Production Company LLC | Nowata, OK 74048 | Oil & Gas Operator | Sep 2025 |
| 505 | Nerco Oil & Gas Inc | | Oil & Gas Operator | Dec 1996 |
| 506 | New Dominion LLC | Tulsa, OK 74119-3220 | Oil & Gas Operator | Oct 2025 |
| 507 | New Era Gas Co Inc | Bull Shoals, AR 72619-0130 | Gas Operator | Mar 2004 |
| 508 | Newell Oil And Gas LLC | Shawnee, OK 74801-5783 | Oil & Gas Operator | Aug 2025 |
| 509 | NFC Petroleum Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1996 |
| 510 | Nichols Operating LLC | Fort Branch, IN 47648 | Oil & Gas Operator | Dec 2021 |
| 511 | Nielson & Associates, Inc | Cody, WY 82414 | Oil & Gas Operator | Feb 2016 |
| 512 | NM&O Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 513 | Norman Kenneth W | Sasakwa, OK 74867-0086 | Oil Operator | Oct 2017 |
| 514 | Northbrook Oil & Gas Co LLC | Norman, OK 73072 | Oil & Gas Operator | Nov 2014 |
| 515 | Northbrook Oil & Gas Company | Norman, OK 73070-4916 | Oil & Gas Operator | Jun 2016 |
| 516 | Nye Oil Company | Oklahoma City, OK 73118-1245 | Oil & Gas Operator | Jun 2004 |
| 517 | O G & E | Oklahoma City, OK 73124 | Oil & Gas Operator | Feb 2014 |
| 518 | Oak Hills Drilling & Oper., LLC | Holdenville, OK 74848 | Oil & Gas Operator | May 2013 |
| 519 | Oak Hills Energy Inc | Holdenville, OK 74848-0470 | Oil & Gas Operator | Sep 2014 |
| 520 | Oakland Petroleum Oper Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 521 | Oil Center Operating Inc | Fort Worth, TX 76102-5108 | Oil & Gas Operator | Apr 2014 |
| 522 | Oil Exploration Of America Inc | Sisseton, SD 57262-9503 | Oil & Gas Operator | Jun 2001 |
| 523 | Oil Recovery Systems Inc | Tulsa, OK 74145-4619 | Oil & Gas Operator | Oct 2025 |
| 524 | Oklahoma Basic Economy Corp | Houston, TX 77002-6003 | Oil & Gas Operator | Apr 2020 |
| 525 | Oklahoma Oil & Gas MGMT Inc | Edmond, OK 73083-6786 | Oil & Gas Operator | Sep 2025 |
| 526 | Oklahoma Prime Energy LLC | Ardmore, OK 73401 | Oil Operator | May 2020 |
| 527 | Oktex Operating LLC | Edmond, OK 73013-1961 | Oil & Gas Operator | May 2020 |
| 528 | Old Dominion Oil Corporation | Oklahoma City, OK 73107 | Oil & Gas Operator | Apr 2009 |
| 529 | Oliphant Gertrud | Holdenville, OK 74848-0849 | Oil Operator | Aug 2013 |
| 530 | Oneok Gas Transportation Co | Tulsa, OK 74121-2089 | Oil & Gas Operator | Oct 2014 |
| 531 | Ovintiv Mid-Continent Inc. | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Oct 2025 |
| 532 | P & H Construction Inc | Wewoka, OK 74884 | Oil & Gas Operator | Jun 2024 |
| 533 | P A Energy Inc | Calvin, OK 74531-0248 | Oil & Gas Operator | Apr 2020 |
| 534 | Pacific Enterprise Oil Co USA | Los Angeles, CA 90071-2005 | Oil & Gas Operator | Aug 2012 |
| 535 | Paleo, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2025 |
| 536 | Paloma Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2018 |
| 537 | Paluca Petroleum Inc | Holdenville, OK 74848 | Oil & Gas Operator | Oct 2025 |
| 538 | Pantera Energy Company | Amarillo, TX 79101 | Oil & Gas Operator | Dec 2025 |
| 539 | Panther Energy Company, LLC | Tulsa, OK 74103 | Oil & Gas Operator | May 2022 |
| 540 | Papal Enterprises Inc | Oklahoma City, OK 73154-1555 | Oil & Gas Operator | Apr 2015 |
| 541 | Par Oil Company Inc | Denver, CO 80201 | Oil & Gas Operator | Jun 2003 |
| 542 | Parkinsol Oil Company | Seminole, OK 74868-1648 | Oil & Gas Operator | Oct 2014 |
| 543 | Parks Bill M | Seminole, OK 74818-1648 | Oil & Gas Operator | Apr 2014 |
| 544 | Patterson George E | Ada, OK 74820-1108 | Oil & Gas Operator | Jul 2016 |
| 545 | Pawnee Petroleum Company | Seminole, OK 74868-0951 | Oil & Gas Operator | Feb 2023 |
| 546 | PCL Energy LLC | Seminole, OK 74868 | Oil & Gas Operator | Oct 2025 |
| 547 | Penn VIrginia MC Operating Co LLC | Houston, TX 77084-7213 | Oil & Gas Operator | Sep 2025 |
| 548 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 549 | Peregrine Petroleum Corp | Oklahoma City, OK 73116-7639 | Oil & Gas Operator | May 2020 |
| 550 | Perkins Nova | Atwood, OK 74827-9738 | Oil Operator | Feb 2014 |
| 551 | Pertex Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 1996 |
| 552 | Petra Petroleum Management LLC | Hotchkiss, CO 81419-0369 | Gas Operator | Sep 2014 |
| 553 | Petro Davis Inc | Oklahoma City, OK 73142-1807 | Oil & Gas Operator | Jan 2013 |
| 554 | Petro Speed Inc | Norman, OK 73069-8116 | Oil & Gas Operator | Mar 2015 |
| 555 | Petro-Met Energy LLC | Edmond, OK 73034-1237 | Oil Operator | Aug 2025 |
| 556 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | Dec 2025 |
| 557 | Petroquest Oil & Gas LLC | Wewoka, OK 74884 | Oil & Gas Operator | Oct 2025 |
| 558 | Phase III Drilling Inc | Wetumka, OK 74883-0333 | Oil & Gas Operator | Sep 2025 |
| 559 | Phillips Oil Operating Co | Enid, OK 73703-4921 | Oil & Gas Operator | May 2019 |
| 560 | Phoenix Operating Company, Inc. | Shreveport, LA 71161 | Oil & Gas Operator | Mar 2015 |
| 561 | Pices Energy Production Co. | Alva, OK 73717-9512 | Oil & Gas Operator | Apr 2014 |
| 562 | Plainsmen Energy LLC | Enid, OK 73703-5747 | Oil & Gas Operator | Oct 2025 |
| 563 | Pogue Randall | Ada, OK 74821-1547 | Oil & Gas Operator | Apr 2014 |
| 564 | Ponder Oil Producers LLC | Okemah, OK 74859 | Oil & Gas Operator | Sep 2025 |
| 565 | Post Oak Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Jul 2013 |
| 566 | Pound Robert M | Bristow, OK 74010 | Oil & Gas Operator | Sep 2014 |
| 567 | Power Fuel Producers Inc | Keller, TX 76244-1059 | Oil & Gas Operator | Sep 2001 |
| 568 | Prairie Wind Oil LLC | Blackwell, OK 74647-7242 | Oil & Gas Operator | Aug 2025 |
| 569 | Pre-MC Inc | Allen, OK 74825 | Oil & Gas Operator | Sep 2025 |
| 570 | Prentice Benny P | Allen, OK 74825-0247 | Oil & Gas Operator | Feb 2007 |
| 571 | Prentice Bradley L | Allen, OK 74825 | Oil & Gas Operator | Sep 2025 |
| 572 | Prentice Bro Oil Operators | Allen, OK 74825 | Oil & Gas Operator | Apr 2014 |
| 573 | Prentice Ed | Allen, OK 74825 | Oil & Gas Operator | Jul 2025 |
| 574 | Presley Operating LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2025 |
| 575 | Primary Natural Resources Inc. | Tulsa, OK 74136-6351 | Oil & Gas Operator | Mar 2023 |
| 576 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 577 | Primexx Operating Corporation | Dallas, TX 75206 | Oil & Gas Operator | Mar 2024 |
| 578 | Pringle Operating Co. | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2015 |
| 579 | Proctor Dale & Mildred | Wetumka, OK 74883-6272 | Gas Operator | Sep 2025 |
| 580 | Prospect Enterprises Inc | Wetumka, OK 74883-0068 | Oil & Gas Operator | Apr 2004 |
| 581 | Prospective Investment & Trading | Scottsdale, AZ 85261-4190 | Oil & Gas Operator | Jun 2016 |
| 582 | Protege Energy LLC | Tulsa, OK 74135 | Oil & Gas Operator | Jan 2018 |
| 583 | Proven Reserves Management, Inc. | Dallas, TX 75370 | Oil & Gas Operator | Oct 2025 |
| 584 | Pryor VIctor W Jr | Holdenville, OK 74848 | Oil & Gas Operator | Apr 2017 |
| 585 | Pumping Services Inc | Seminole, OK 74868-2421 | Oil & Gas Operator | Jul 2025 |
| 586 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 587 | Quench Oil & Gas Inc | Plano, TX 75075-2902 | Oil & Gas Operator | Apr 2009 |
| 588 | Questar Explor & Prod Co | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2017 |
| 589 | Quintana Pet Okla Inc | Houston, TX 77002 | Oil & Gas Operator | Jun 1998 |
| 590 | R & B Oil & Gas Inc | Attica, KS 67009 | Oil & Gas Operator | Jun 2025 |
| 591 | R B Energy Inc | Manchester, KY 40962 | Oil & Gas Operator | Jan 2015 |
| 592 | R Baker Oil LLC | Okemah, OK 74859 | Oil & Gas Operator | Oct 2025 |
| 593 | R C Taylor Operating Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Oct 2025 |
| 594 | R H S Inc | Ada, OK 74821-1252 | Oil & Gas Operator | Apr 2020 |
| 595 | R J Exploration LLC | Konawa, OK 74849 | Oil & Gas Operator | Oct 2025 |
| 596 | R K R Exploration | Seminole, OK 74868-9754 | Oil & Gas Operator | Mar 2015 |
| 597 | R W Production Company Inc | Ada, OK 74821-2693 | Oil & Gas Operator | Apr 2011 |
| 598 | Ra-Jac LLC | Norman, OK 73072 | Oil & Gas Operator | Oct 2025 |
| 599 | Radford Dale | Konawa, OK 74849 | Oil & Gas Operator | Oct 2025 |
| 600 | Raf Oil Company | Oklahoma City, OK 73120-1944 | Oil & Gas Operator | Jul 2013 |