| 601 | O'Brien Oil LLC | Guthrie, OK 73044-3154 | Oil & Gas Operator | Apr 2020 |
| 602 | O'Neal Oil & Gas Co | Fort Worth, TX 76107-1479 | Oil & Gas Operator | Feb 2024 |
| 603 | Oakland Petroleum Oper Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 604 | Oex-1 LLC | Tulsa, OK 74105-5153 | Oil & Gas Operator | Dec 2023 |
| 605 | Ofs-Tulsa Corporation | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 1997 |
| 606 | Oil Investors Inc | | Oil & Gas Operator | Mar 2024 |
| 607 | Oil Ventures LTD | | Oil & Gas Operator | Jan 2013 |
| 608 | Okie Crude Company | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2024 |
| 609 | Oklahoma Energy Acquisitions LP | | Oil & Gas Operator | Jan 2024 |
| 610 | Oklahoma Equipment & Salvage | Oklahoma City, OK 73120-5903 | Oil & Gas Operator | Mar 2015 |
| 611 | Oklahoma Liquid Resources Inc | Owasso, OK 74055-0841 | Oil & Gas Operator | Jan 2024 |
| 612 | Oklahoma Oil & Gas MGMT Inc | | Oil & Gas Operator | Jan 2024 |
| 613 | Oklahoma Petroleum Allies LLC | Ardmore, OK 73401 | Oil Operator | Oct 2023 |
| 614 | Okmar Oil Company | Marietta, OH 45750 | Oil & Gas Operator | Jun 2005 |
| 615 | Omimex International Corporation | Fort Worth, TX 76103-2300 | Oil & Gas Operator | Jan 2024 |
| 616 | Oneok Gas Transportation Co | Tulsa, OK 74121-2089 | Oil & Gas Operator | Oct 2014 |
| 617 | Oneok Resources Company | Tulsa, OK 74102 | Oil & Gas Operator | Feb 2017 |
| 618 | Optima Exploration LLC | | Oil & Gas Operator | Mar 2015 |
| 619 | Opubco Resources Of TX Inc | Dallas, TX 75231 | Oil & Gas Operator | Sep 2005 |
| 620 | Orason Resources Inc | Tulsa, OK 74169-1225 | Oil & Gas Operator | Nov 2006 |
| 621 | Orion Exploration LLC | Tulsa, OK 74105-5153 | Oil & Gas Operator | Apr 2015 |
| 622 | Orion Exploration Partners LLC | | Oil & Gas Operator | Jul 2020 |
| 623 | Osage Exploration & Development Inc | | Oil & Gas Operator | Oct 2016 |
| 624 | Oso Resources LLC | | Oil & Gas Operator | Jan 2024 |
| 625 | Osterhout Phillip L | Drumright, OK 74030-0693 | Oil & Gas Operator | Jan 2014 |
| 626 | Outlaw Oil And Gas LLC | Gillette, WY 82716 | Oil & Gas Operator | Jan 2024 |
| 627 | Ovintiv Mid-Continent Inc. | The Woodlands, TX 77380-2764 | Oil & Gas Operator | Jan 2024 |
| 628 | Pacific Enterprise Oil Co USA | Los Angeles, CA 90071-2005 | Oil & Gas Operator | Aug 2012 |
| 629 | Pacific Enterprises Royalty Co | Oklahoma City, OK 73101 | Oil & Gas Operator | Feb 2002 |
| 630 | Pan Western Energy Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Apr 2024 |
| 631 | Panadero Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Apr 2002 |
| 632 | Panexco Operating LLC | Oklahoma City, OK 73103-2203 | Oil & Gas Operator | Oct 2014 |
| 633 | Papal Enterprises Inc | Oklahoma City, OK 73154-1555 | Oil & Gas Operator | Apr 2015 |
| 634 | Paramount Petroleum Corp | Dallas, TX 75374 | Oil Operator | Dec 2000 |
| 635 | Pardee Production Co. | Skiatook, OK 74070 | Oil & Gas Operator | Mar 2021 |
| 636 | Parker & Parsley Dev Co | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 637 | Parsons Engineering Corporation | Tulsa, OK 74137-7505 | Oil & Gas Operator | Oct 2017 |
| 638 | Patina Oil & Gas Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2016 |
| 639 | Patina Oklahoma Corp | Duncan, OK 73533-9523 | Oil & Gas Operator | Nov 2014 |
| 640 | Payne Exploration Company | Crescent, OK 73028-0502 | Oil & Gas Operator | Jan 2024 |
| 641 | Payne W C Family Trust | Oklahoma City, OK 73116-9044 | Oil & Gas Operator | Mar 2015 |
| 642 | PBT Enterprises Inc | Garber, OK 73738-0262 | Oil & Gas Operator | May 2023 |
| 643 | Pearl Petroleum Inc | Lawton, OK 73501-5821 | Oil & Gas Operator | Jan 2014 |
| 644 | Pedestal Oil Company Inc | Oklahoma City, OK 73101-1522 | Oil & Gas Operator | May 2019 |
| 645 | Pegasus Energy Corporation | Oklahoma City, OK 73162 | Oil & Gas Operator | Mar 2015 |
| 646 | Pelican Production Company | New Orleans, LA 70130-2477 | Oil & Gas Operator | Mar 2014 |
| 647 | Penn VIrginia MC Operating Co LLC | Houston, TX 77084-7213 | Oil & Gas Operator | Feb 2024 |
| 648 | Pepin Oil Co | Stillwater, OK 74076 | Oil & Gas Operator | Oct 2013 |
| 649 | Performance Petroleum Company LLC | Barnsdall, OK 74002-0628 | Oil & Gas Operator | Jan 2024 |
| 650 | Petro Davis Inc | Oklahoma City, OK 73142-1807 | Oil & Gas Operator | Jan 2013 |
| 651 | Petro Speed Inc | Norman, OK 73069-8116 | Oil & Gas Operator | Mar 2015 |
| 652 | Petro-Management Assoc., Inc. | Edmond, OK 73083-2346 | Oil & Gas Operator | Jun 2007 |
| 653 | Petroleum Properties MGMT. Co. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2014 |
| 654 | Petroleum Reserve Corporation | Plymouth MTNG, PA 19462 | Oil & Gas Operator | May 2008 |
| 655 | Petroleum Resources Co | Wichita, KS 67206 | Oil & Gas Operator | May 2000 |
| 656 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | Apr 2024 |
| 657 | Phillips Oil Operating Co | Enid, OK 73703-4921 | Oil & Gas Operator | May 2019 |
| 658 | Plains Liquids Transport Inc | Houston, TX 77002 | Oil & Gas Operator | May 1996 |
| 659 | Plains Marketing & Trans Inc | Houston, TX 76002 | Oil & Gas Operator | Oct 1998 |
| 660 | Plains Marketing LP | Cushing, OK 74023 | Oil & Gas Operator | Dec 2022 |
| 661 | Plainsmen Energy LLC | | Oil & Gas Operator | Feb 2024 |
| 662 | Plotner Oil Company | Oklahoma City, OK 73123-1427 | Oil & Gas Operator | Feb 2024 |
| 663 | Plotner Ralph Oil & Gas Inv Co | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2021 |
| 664 | Post Oak Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Jul 2013 |
| 665 | Powerline Energy Corporation | Arlington, TX 76015 | Oil & Gas Operator | Apr 2024 |
| 666 | Prentice Napier & Green Inc | Oklahoma City, OK 73172-1424 | Oil & Gas Operator | Feb 2024 |
| 667 | Presidio Petroleum LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2024 |
| 668 | Presley Operating LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2024 |
| 669 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2024 |
| 670 | Prime Energy Corp | Charleston, WV 25301-1707-1707 | Oil & Gas Operator | Sep 2015 |
| 671 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Apr 2024 |
| 672 | Primexx Operating Corporation | Dallas, TX 75206 | Oil & Gas Operator | Jan 2024 |
| 673 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 674 | Producers Oil Company | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2007 |
| 675 | Proven Reserves Management, Inc. | Dallas, TX 75370 | Oil & Gas Operator | Jan 2024 |
| 676 | Providence Oil & Gas Corp | Tulsa, OK 74135-5463 | Oil & Gas Operator | May 2005 |
| 677 | Psec Inc | Tulsa, OK 74102-0871 | Oil & Gas Operator | Dec 2016 |
| 678 | PXP Gulf Coast Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 679 | Pyramid Energy Inc | San Antonio, TX 78216 | Oil & Gas Operator | Feb 2012 |
| 680 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Jan 2024 |
| 681 | Quad J Oil & Gas LLC | Crescent, OK 73028-0037 | Oil & Gas Operator | Feb 2024 |
| 682 | Quest Property Inc | Oklahoma City, OK 73123-3238 | Oil & Gas Operator | Jan 2024 |
| 683 | Questar Energy Trading | Salt Lake City, UT 84145-0601 | Oil & Gas Operator | Mar 2020 |
| 684 | Questar Explor & Prod Co | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2017 |
| 685 | R & B Trucking | Crescent, OK 73028-0775 | Oil & Gas Operator | Nov 2021 |
| 686 | R & N Associates | Grapevine, TX 76051 | Oil & Gas Operator | Jan 2024 |
| 687 | R & N Oil Company | Fairfax, OK 74637 | Oil & Gas Operator | May 2013 |
| 688 | R C Taylor Operating Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2024 |
| 689 | R E Blaik Inc | Edmond, OK 73013-6675 | Oil & Gas Operator | Feb 2024 |
| 690 | R L Clampitt & Associates LLC | Bartlesville, OK 74006-3313 | Oil & Gas Operator | Feb 2024 |
| 691 | Ra-Jac LLC | Norman, OK 73070-4656 | Oil & Gas Operator | Feb 2024 |
| 692 | Rainwater A L | Okmulgee, OK 74447 | Oil & Gas Operator | Jan 2013 |
| 693 | Ram Asset Management Co | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2015 |
| 694 | Ramco Oil & Gas Inc | Midland, TX 79701 | Oil & Gas Operator | Nov 2006 |
| 695 | Ramsey Engineering Inc | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 1993 |
| 696 | Ramsey Nichols Operating Company LLC | | Oil & Gas Operator | Feb 2024 |
| 697 | Ramsey Property Management LLC | Oklahoma City, OK 73120-1955 | Oil & Gas Operator | Jan 2024 |
| 698 | Ramsey Property MGMT Inc | Oklahoma City, OK 73120-1955 | Oil & Gas Operator | Mar 2019 |
| 699 | Randall E James Oil Company | Guthrie, OK 73044-9352 | Oil & Gas Operator | Jan 2024 |
| 700 | Randy Inc | Dover, OK 73734-0102 | Oil & Gas Operator | Jan 2024 |