| 601 | Fortitude Exploration Co | | Oil & Gas Operator | Aug 2025 |
| 602 | Fortress Energy Corp | Pittsburgh, PA 15217-4207 | Oil & Gas Operator | Dec 2023 |
| 603 | Fortson Oil | | Oil & Gas Operator | Jan 1998 |
| 604 | Fortson Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2020 |
| 605 | Fortuna Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2014 |
| 606 | Fortuna Exploration, Inc. | Abilene, TX 79602 | Oil & Gas Operator | Dec 2025 |
| 607 | Fortuna Resources Dvlpment, LLC | Houston, TX 77055 | Oil & Gas Operator | Dec 2025 |
| 608 | Fortune Energy, Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2025 |
| 609 | Fortune Gas & Oil | Shreveport, LA 71118-3457 | Oil & Gas Operator | Dec 2002 |
| 610 | Fortune Gas & Oil, Inc. | | Oil & Gas Operator | Apr 2004 |
| 611 | Fortune Natural Resources Corp. | Houston, TX 77067 | Oil & Gas Operator | Dec 2003 |
| 612 | Fortune Oil LTD | Salt Lake City, UT 84106 | Oil & Gas Operator | May 1987 |
| 613 | Fortune Operating Company | Willis, TX 77378 | Oil & Gas Operator | Dec 2025 |
| 614 | Fortune Operating, Inc. | Bowling Green, KY 42104 | Oil & Gas Operator | Dec 2025 |
| 615 | Fortune Petroleum Corporation | | Oil & Gas Operator | Dec 1994 |
| 616 | Fortune Production Co. | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2008 |
| 617 | Fortune Resources LLC | Longview, TX 75604 | Oil & Gas Operator | Dec 2025 |
| 618 | Fortune-Shelby | | Oil & Gas Operator | Mar 1989 |
| 619 | Fortune-Western | | Oil Operator | Dec 1989 |
| 620 | Forty Acres Energy, LLC | Houston, TX 77079173 | Oil & Gas Operator | Nov 2025 |
| 621 | Fortyfive Energy LLC | | Gas Operator | Dec 2025 |
| 622 | Forum Exploration Co., L.P. | Tyler, TX 75710 | Oil & Gas Operator | Apr 2010 |
| 623 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2025 |
| 624 | Foshee Operating, LLC | | Oil & Gas Operator | Jun 2004 |
| 625 | Foss, Arthur & Ann | Corfu, NY 14036 | Gas Operator | Dec 2024 |
| 626 | Fossil Creek Energy Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2025 |
| 627 | Fossil Creek Energy, LLC | Russell, KS 67665 | Oil Operator | Sep 2025 |
| 628 | Fossil Creek Resources LLC | Arlington, TX 76011-5597 | Oil & Gas Operator | Mar 2015 |
| 629 | Fossil Energy Inc | Austin, TX 78746 | Oil & Gas Operator | Dec 2025 |
| 630 | Fossil Energy, LLC | Russell, KS 67665 | Oil Operator | Sep 2025 |
| 631 | Fossil Fuel Inc | Dallas, TX BAD ADDR | Oil & Gas Operator | Dec 1998 |
| 632 | Fossil Fuels Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2000 |
| 633 | Fossil Operating, Inc. | Dallas, TX 75238 | Oil & Gas Operator | Dec 2025 |
| 634 | Fossil Petroleum LLC | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2025 |
| 635 | Fossil Resources LLC | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 636 | Fossil Resources, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Oct 2017 |
| 637 | Fossil Rock Resources, Inc. | Fort Worth, TX 76185 | Oil & Gas Operator | May 2016 |
| 638 | Foster Energy Company | Tilden, TX 78072 | Oil & Gas Operator | Sep 2024 |
| 639 | Foster Energy Group, LLC | Wolfforth, TX 79382 | Oil & Gas Operator | Nov 2025 |
| 640 | Foster Gas Corporation | Brownwood, TX 76801 | Oil & Gas Operator | Jan 2009 |
| 641 | Foster Oil & Gas | Bartlesville, OK 74005 | Oil & Gas Operator | Mar 2014 |
| 642 | Foster Oil LLC | | Oil Operator | Sep 2025 |
| 643 | Foster Well Service, Inc. | Conroe, TX 77305 | Oil & Gas Operator | Jan 2000 |
| 644 | Foster, Charles R. Co. | Haskell, TX 79521 | Oil & Gas Operator | Aug 2002 |
| 645 | Foster, Randy | New Braunfels, TX 78132 | Oil & Gas Operator | Feb 2021 |
| 646 | Foster-Brown Operations, Inc. | | Oil & Gas Operator | Apr 2003 |
| 647 | Foti Oil & Gas, Inc. | | Oil Operator | Sep 1986 |
| 648 | Foundation Energy Management, LLC | Addison, TX 75001 | Oil & Gas Operator | Dec 2025 |
| 649 | Foundation Energy Managment LLC | Addison, TX 74119 | Oil & Gas Operator | Oct 2025 |
| 650 | Foundation Energy MGT, LLC | | Oil & Gas Operator | Jan 2014 |
| 651 | Foundation Oil Company, Inc. | Kingwood, TX 77325 | Oil & Gas Operator | Dec 2025 |
| 652 | Founders Oil & Gas Operating,LLC | Arlington, TX 76011 | Oil & Gas Operator | Jul 2023 |
| 653 | Fountain Oil And Gas Co. | | Gas Operator | Dec 1993 |
| 654 | Fountainhead Resources LTD | | Oil & Gas Operator | Apr 2016 |
| 655 | Four - S Oil Company, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2008 |
| 656 | Four A Oil Company Inc | Copan, OK 74022 | Oil Operator | Aug 2022 |
| 657 | Four Aces Company | Borger, TX 79008 | Oil & Gas Operator | Mar 1995 |
| 658 | Four Brothers Inc | | Oil & Gas Operator | Jan 2020 |
| 659 | Four C Oil & Gas Corp. | Dallas, TX 75206 | Oil & Gas Operator | Jan 2024 |
| 660 | Four Corners Energy, LLC | Gulf Breeze, FL 32563 | Oil & Gas Operator | Dec 2025 |
| 661 | Four Corners Exploration Co | Farmington, NM 87499 | Oil & Gas Operator | Nov 2025 |
| 662 | Four Corners Oil, LLC | Cape Fair, MO 65624 | Oil Operator | Sep 2025 |
| 663 | Four Corners Petroleum II, LLC | Denver, CO 80215 | Oil & Gas Operator | Feb 2023 |
| 664 | Four Diamond Operating, LLC | Kilgore, TX 75662 | Oil Operator | Dec 2025 |
| 665 | Four Forty One Oil Co. | Natalia, TX 78059 | Oil & Gas Operator | Dec 2025 |
| 666 | Four H Oil Properties | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 667 | Four K Production | Pampa, TX 79065 | Oil & Gas Operator | Dec 2025 |
| 668 | Four Kin Oil Co | Muenster, TX 76252 | Oil & Gas Operator | Dec 2001 |
| 669 | Four Leaf Land Company | West Union, WV 26456-0000 | Oil & Gas Operator | Dec 2021 |
| 670 | Four North Inc | Atoka, OK 74525 | Oil Operator | Feb 2004 |
| 671 | Four R Operating Company, LLC | Smackover, AR 71762 | Oil & Gas Operator | Jan 2025 |
| 672 | Four Rivers Exploration, Inc. | | Oil & Gas Operator | Sep 2002 |
| 673 | Four Seas Exploration LLC | Oklahoma City, OK 73101-1557 | Oil & Gas Operator | Dec 2019 |
| 674 | Four Seasons, Inc. | | Oil & Gas Operator | Jun 1983 |
| 675 | Four Sevens Oil Co., LTD. | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2001 |
| 676 | Four Sevens Operating Co., LTD. | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 677 | Four Square Oil Company Inc | Kellyville, OK 74039 | Oil Operator | Mar 2011 |
| 678 | Four Square Production, L.L.C. | Houston, TX 77079 | Oil & Gas Operator | Aug 2004 |
| 679 | Four Star Development Corp. | | Oil & Gas Operator | Feb 2013 |
| 680 | Four Star Oil & Gas Company | Houston, TX 77252 | Oil & Gas Operator | Sep 2025 |
| 681 | Four Star Oil - | | Oil Operator | Dec 1987 |
| 682 | Four Star Oil Company | | Oil & Gas Operator | May 2015 |
| 683 | Four Starr Energy, Inc. | Dallas, TX 75243 | Gas Operator | May 2016 |
| 684 | Four Starr Production, LLC | Dallas, TX 75243 | Oil & Gas Operator | Dec 2025 |
| 685 | Four States Petr | | Oil & Gas Operator | Nov 1990 |
| 686 | Four Teams Oil Production & Exploration Inc. | | Oil & Gas Operator | Nov 2025 |
| 687 | Four W Oil Co., LLC | | Oil Operator | Dec 2024 |
| 688 | Four-A Energy LLC | Cody, WY 82414 | Oil Operator | Nov 2025 |
| 689 | Four-C Management & Industries | Rockdale, TX 76567 | Oil & Gas Operator | Aug 2008 |
| 690 | Four-J Oil Ops | Osawatomie, KS 66064 | Oil Operator | Mar 1998 |
| 691 | Four-O-One Corporation | Edmond, OK 73013-1977 | Oil & Gas Operator | Mar 2015 |
| 692 | Four-S Oil Co., LTD. | Kilgore, TX 75663 | Oil Operator | Apr 2007 |
| 693 | Four-Way Oper In | | Oil Operator | Aug 1994 |
| 694 | Four-Way Operating, Inc. | Great Bend, KS 67530 | Oil Operator | Sep 2013 |
| 695 | Fourcooks Oil & Gas, LLC | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 696 | Fourpoint Energy, LLC | Denver, CO 80206 | Oil & Gas Operator | Dec 2025 |
| 697 | Fourpoint Resources, LLC | Denver, CO 80206 | Oil & Gas Operator | Nov 2025 |
| 698 | Fourstar Resources LLC | Westlake, TX 76262 | Oil Operator | Nov 2025 |
| 699 | Fourth Floor Operating LLC | Austin, TX 78746 | Oil & Gas Operator | Dec 2025 |
| 700 | Fourth Quarter Program | Boulder, CO 80306 | Oil Operator | Feb 2006 |