| 601 | Lee Mills | | Oil Operator | Feb 1992 |
| 602 | Lee Of Tulsa Oil & Gas Inc | Tulsa, OK 74114-5634 | Oil & Gas Operator | Dec 2021 |
| 603 | Lee Phillips Oil Company | | Oil Operator | Dec 2024 |
| 604 | Lee Production Co. | Monahans, TX 79756 | Oil & Gas Operator | Apr 2025 |
| 605 | Lee Ron | Emory, TX 75440 | Oil Operator | Feb 2025 |
| 606 | Lee Roy Daigle | | Oil Operator | Dec 1992 |
| 607 | Lee'S Summit Gas Co. | | Gas Operator | Dec 1933 |
| 608 | Lee, R.A., Inc. | | Oil Operator | Nov 1972 |
| 609 | Lee-Walker Mineral, LLC | Houston, TX 77269 | Oil Operator | Apr 2025 |
| 610 | Leed Energy LLC | Purcell, OK 73080-1383 | Oil & Gas Operator | Jan 2025 |
| 611 | Leede Oil & Gas Inc. | Greenwood VLG, CO 80111 | Oil & Gas Operator | Aug 2003 |
| 612 | Leedy Oil Produc | | Oil & Gas Operator | Dec 1995 |
| 613 | Leedy Oil Producers | | Oil Operator | Nov 2009 |
| 614 | Leejan Oil Company | Amarillo, TX 79109 | Oil & Gas Operator | Apr 2025 |
| 615 | Leeman Don J | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 1998 |
| 616 | Leeman Energy Co | | Oil & Gas Operator | Jan 1987 |
| 617 | Leeman Energy Corporation | Oklahoma City, OK 73118-1802 | Oil & Gas Operator | Mar 2015 |
| 618 | Leeper Oil Exp. & Prod. Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2005 |
| 619 | Lees Petroleum LLC | | Oil & Gas Operator | Jul 2000 |
| 620 | Leeward Operators LLC | | Oil & Gas Operator | Jul 2011 |
| 621 | Leexus Oil & Gas L.L.P. | Giddings, TX 78942 | Oil & Gas Operator | Jun 2008 |
| 622 | Leexus Oil LLC | Giddings, TX 78942 | Oil & Gas Operator | Apr 2025 |
| 623 | Leexus Operating Company | Austin, TX 78734 | Oil & Gas Operator | Aug 2007 |
| 624 | Lefco Resources LLC | Henryetta, OK 74437 | Gas Operator | Jan 2025 |
| 625 | Leffel'S, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Jun 2020 |
| 626 | Lefforge & Klein | Amarillo, TX 79114 | Gas Operator | Jun 1997 |
| 627 | Lefort, Marian G. | Strykersville, NY 14145 | Gas Operator | Dec 2023 |
| 628 | Left Behind Recovery, LLC | Luling, TX 78648 | Oil & Gas Operator | Apr 2025 |
| 629 | Leg Up Operating Company LLC | Tulsa, OK 74135 | Oil Operator | Jan 2025 |
| 630 | Legacy - M & K Corporation | Dallas, TX 75231-0969 | Oil & Gas Operator | Jan 2025 |
| 631 | Legacy Acres, LLC | South Dayton, NY 14138 | Gas Operator | Dec 2023 |
| 632 | Legacy Corporation, The | Cedar Park, TX 78613 | Oil & Gas Operator | Jun 2004 |
| 633 | Legacy Energy Inc | Carpinteria, CA 93013 | Oil & Gas Operator | Jun 2012 |
| 634 | Legacy Energy LLC | Russell, KS 67665 | Oil Operator | Jan 2025 |
| 635 | Legacy Energy Services | Jourdanton, TX 78026 | Oil Operator | Apr 2025 |
| 636 | Legacy Energy Services LLC | Stillwater, OK 74074 | Oil & Gas Operator | Jan 2025 |
| 637 | Legacy Exploration, LLC I | Dallas, TX 75201 | Oil & Gas Operator | Apr 2025 |
| 638 | Legacy Oil & Gas ND, Inc. | | Oil & Gas Operator | Feb 2016 |
| 639 | Legacy Oil & Gas, Inc. | Portland, TX 78374 | Oil & Gas Operator | Apr 2025 |
| 640 | Legacy Oil, LLC | Falls Of Rough, KY 40119 | Oil Operator | Dec 2023 |
| 641 | Legacy Oklahoma Operators LLC | Shawnee, OK 74804-1447 | Oil & Gas Operator | Jan 2025 |
| 642 | Legacy Operating Company | | Oil & Gas Operator | Aug 1992 |
| 643 | Legacy Operating Company, LLC | Dallas, TX 75205 | Oil Operator | Jun 2024 |
| 644 | Legacy Petroleum Corporation | Dallas, TX 75225 | Oil & Gas Operator | Mar 2019 |
| 645 | Legacy Petroleum LLC | Tulsa, OK 74135 | Oil & Gas Operator | Dec 2023 |
| 646 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Apr 2025 |
| 647 | Legacy Resources Co., L.P. | | Oil & Gas Operator | Apr 2019 |
| 648 | Legado DJ, LLC | | Oil Operator | Jul 2011 |
| 649 | Legado Gulf Coast, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 2010 |
| 650 | Legado Midcon, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | May 2010 |
| 651 | Legado Permian, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | May 2013 |
| 652 | Legend Energy Corporation | Stillwater, OK 74074-1721 | Oil & Gas Operator | Aug 2022 |
| 653 | Legend Energy LLC | Cherryvale, KS 67335 | Oil Operator | Dec 2024 |
| 654 | Legend Energy Texas, LLC | Arlington, TX 76002 | Oil & Gas Operator | Apr 2025 |
| 655 | Legend Fund, LLC | | Oil & Gas Operator | Jan 2025 |
| 656 | Legend Natural Gas II, LP | Houston, TX 77094 | Oil & Gas Operator | Feb 2015 |
| 657 | Legend Natural Gas III, LP | Houston, TX 77094 | Oil & Gas Operator | Feb 2015 |
| 658 | Legend Natural Gas IV, LP | Houston, TX 77094 | Oil & Gas Operator | Feb 2015 |
| 659 | Legend Natural Gas, LP | Houston, TX 77084 | Oil & Gas Operator | Aug 2004 |
| 660 | Legend Oil & Gas LTD. | Alpharetta, GA 30022 | Oil Operator | Mar 2015 |
| 661 | Legend Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | May 2010 |
| 662 | Legendary Oil Co., Inc. | | Oil Operator | Feb 2004 |
| 663 | Legendary Well Service, Inc. | | Oil Operator | Jan 1996 |
| 664 | Leger Production Company, Inc. | | Oil & Gas Operator | Apr 1984 |
| 665 | Legg, Raymond | | Oil Operator | Dec 2010 |
| 666 | Leggett Oil Company | Dallas, TX 75379 | Oil & Gas Operator | Oct 1999 |
| 667 | Leggett Petroleum, L.L.C. | | Oil & Gas Operator | Dec 2020 |
| 668 | Legleiter, Julius A. | Hays, KS 67601 | Oil Operator | Apr 1996 |
| 669 | Legrand, Buck | Sedan, KS 67361 | Oil Operator | Jun 1994 |
| 670 | Lehnertz, G. M. | Tyler, TX 75702 | Oil & Gas Operator | Dec 1998 |
| 671 | Lehnertz-Faulkner, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Feb 2023 |
| 672 | Leicht, Cecil | Streetman, TX 75859 | Oil & Gas Operator | Feb 1998 |
| 673 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 674 | Leighty, Roger Operator | Lawrenceville, IL 62439 | Oil & Gas Operator | Oct 1997 |
| 675 | Leiker, Edward P. | Hays, KS 67601 | Oil Operator | Apr 1992 |
| 676 | Leis Oil Services, LLC | Yates Center, KS 66783 | Oil Operator | Jul 2023 |
| 677 | Leis, John E. | Yates Center, KS 66783 | Oil Operator | Dec 2024 |
| 678 | Leis, Ryan M. | Scottsdale, AZ 85258 | Oil & Gas Operator | Dec 2009 |
| 679 | Leis, Steven A. | Yates Center, KS 66783 | Oil Operator | Dec 2024 |
| 680 | Leis, VIctor J. | Paola, KS 66071 | Oil & Gas Operator | Dec 2024 |
| 681 | Leith Operations | | Oil Operator | Jul 1989 |
| 682 | Lejan, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Apr 2025 |
| 683 | Lekan James V | Ashland, OH 44805 | Oil & Gas Operator | Dec 1997 |
| 684 | Leland Oil & Gas, LLC | | Oil & Gas Operator | Feb 2025 |
| 685 | Leland Petroleum Production Inc | | Oil & Gas Operator | Dec 2007 |
| 686 | Lem Operating Co., Inc. | Colorado City, TX 79512 | Oil & Gas Operator | Nov 2012 |
| 687 | Lema Petroleum Inc | Seminole, OK 74868 | Oil & Gas Operator | Jan 2025 |
| 688 | Lemasters, Charles A. | Jacksonburg, WV 26377-0000 | Oil & Gas Operator | Dec 2021 |
| 689 | Lemay Oil Company | Snyder, TX 79549 | Oil & Gas Operator | Jun 2002 |
| 690 | Lemley Oil Corporation | Sulphur, OK 73086-9316 | Oil & Gas Operator | Jan 2025 |
| 691 | Lemmons Jack | Cleveland, OK 74020-7023 | Oil Operator | Jan 2015 |
| 692 | Lemon, Richard F. Jr. | Carrollton, TX 75006 | Oil & Gas Operator | Apr 2025 |
| 693 | Lenape Resources Corp | | Oil & Gas Operator | Dec 2000 |
| 694 | Lenape Resources LLC | Alexander, NY 14005 | Oil & Gas Operator | Dec 2023 |
| 695 | Lendrum Energy LLC | Cranberry, PA 16319-4009 | Oil & Gas Operator | Dec 2023 |
| 696 | Lenert & Pettitt, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 1994 |
| 697 | Lengacher William P | Creston, OH 44217 | Oil & Gas Operator | Dec 2022 |
| 698 | Lenhart Oil Company | Cashion, OK 73016-0188 | Oil & Gas Operator | Jul 2016 |
| 699 | Lennon Oil Inc. | Corsicana, TX 75110 | Oil & Gas Operator | Oct 2008 |
| 700 | Leo Michaelis Oil Operator | | Oil Operator | Oct 2002 |