| 2601 | Lancer Resources Company | | Oil & Gas Operator | Jan 1998 |
| 2602 | Land & Natural Res. Dev., Inc. | | Oil & Gas Operator | Apr 2007 |
| 2603 | Landmark Venture Group No. 1, Inc. | | Oil & Gas Operator | Jan 2025 |
| 2604 | Landmark Venture Group, Inc. | | Oil Operator | Dec 2008 |
| 2605 | Lanford Drilling Co., Inc. | | Oil Operator | Jun 1996 |
| 2606 | Lankford & Nance | | Gas Operator | Dec 2010 |
| 2607 | Lanmarc Resources | | Oil Operator | Dec 2003 |
| 2608 | Lanoco, Inc. | | Oil & Gas Operator | Sep 2002 |
| 2609 | Lapis Operating, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jul 2015 |
| 2610 | Largo Oil Company | Longview, TX 75606 | Oil & Gas Operator | Apr 2025 |
| 2611 | Lark Production, Inc. | | Oil & Gas Operator | Mar 2023 |
| 2612 | Las Services, Inc. | | Oil & Gas Operator | Oct 1997 |
| 2613 | Laser Gas Company I, LLC | | Oil Operator | Aug 2007 |
| 2614 | Lasmo Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2024 |
| 2615 | Laster Welding And Well Serv, Inc. | | Gas Operator | Jul 2020 |
| 2616 | Lastrada Oil And Gas LTD | | Oil & Gas Operator | May 1992 |
| 2617 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 2618 | Latexo Oil & Gas Co. | | Oil Operator | Sep 1986 |
| 2619 | Latham & Bonner | | Oil Operator | Aug 1987 |
| 2620 | Latham Exploration Company Inc | | Oil & Gas Operator | Aug 1992 |
| 2621 | Latham Production & Service Co | | Oil Operator | Jul 1989 |
| 2622 | Latham, Bonner & Hall | | Oil Operator | Mar 1988 |
| 2623 | Laurel Operating Company, Inc. | Stillwater, OK 74074-3025 | Oil & Gas Operator | Jan 2025 |
| 2624 | Lavaca River Operating Co., LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Apr 2025 |
| 2625 | Lavino Oil And Gas Company | | Oil & Gas Operator | Aug 1989 |
| 2626 | Lawson Engineering, Inc. | | Oil & Gas Operator | Dec 1984 |
| 2627 | Lax, Inc. | | Oil & Gas Operator | Nov 1987 |
| 2628 | Layline Petroleum I, LLC | Houston, TX 77024 | Oil & Gas Operator | May 2013 |
| 2629 | Layton Energy Inc. | Houston, TX 77027 | Oil & Gas Operator | Apr 2025 |
| 2630 | Layton Oil Co. | | Oil Operator | Feb 1994 |
| 2631 | Lea Exploration, Inc. | | Oil & Gas Operator | Nov 1989 |
| 2632 | Leads Resources, L.L.C. | | Oil & Gas Operator | Jan 2017 |
| 2633 | Lear Gas Transmission | | Oil Operator | Aug 1989 |
| 2634 | Lear Petroleum Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Aug 1999 |
| 2635 | Leatherman Creek, Inc. | | Oil Operator | Jul 2001 |
| 2636 | Lebus Oilfield Service Co | | Oil Operator | Sep 2009 |
| 2637 | Lee Mills | | Oil Operator | Feb 1992 |
| 2638 | Lee Roy Daigle | | Oil Operator | Dec 1992 |
| 2639 | Leeward Operators LLC | | Oil & Gas Operator | Jul 2011 |
| 2640 | Legacy Energy LLC | Russell, KS 67665 | Oil Operator | Jan 2025 |
| 2641 | Legacy Operating Company | | Oil & Gas Operator | Aug 1992 |
| 2642 | Legacy Resources Co., L.P. | | Oil & Gas Operator | Apr 2019 |
| 2643 | Legend Fund, LLC | | Oil & Gas Operator | Jan 2025 |
| 2644 | Legendary Oil Co., Inc. | | Oil Operator | Feb 2004 |
| 2645 | Legendary Well Service, Inc. | | Oil Operator | Jan 1996 |
| 2646 | Leger Production Company, Inc. | | Oil & Gas Operator | Apr 1984 |
| 2647 | Leggett Petroleum, L.L.C. | | Oil & Gas Operator | Dec 2020 |
| 2648 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 2649 | Lenape Resources Corp | | Oil & Gas Operator | Dec 2000 |
| 2650 | Lenert & Pettitt, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 1994 |
| 2651 | Leo Vesenmeir, Jr. | | Oil & Gas Operator | Jul 1987 |
| 2652 | Leo Windham | | Oil Operator | Jul 1992 |
| 2653 | Leroy W. James | | Oil & Gas Operator | Oct 1991 |
| 2654 | Leshen Energy USA LLC | | Oil Operator | Jan 2025 |
| 2655 | Levinson Partners Corporation | Denver, CO 80202 | Oil & Gas Operator | Jul 1995 |
| 2656 | Lewis & Manziel | | Oil Operator | Apr 1989 |
| 2657 | Lewis Operating Company | Holliday, TX 76366 | Oil & Gas Operator | Apr 2025 |
| 2658 | Lewis Williams | | Oil & Gas Operator | Feb 1991 |
| 2659 | Lexico Exploration | | Oil Operator | Mar 1986 |
| 2660 | LGS Exploration Program | | Gas Operator | Jul 1990 |
| 2661 | LGS Exploration, Inc. | | Oil & Gas Operator | Jan 1991 |
| 2662 | LHC Petroleum Corporation | | Oil & Gas Operator | Jul 2001 |
| 2663 | Li'L Sugar Oil Company | | Oil Operator | Nov 2019 |
| 2664 | Liberty Exploration Co. | | Oil Operator | Apr 1987 |
| 2665 | Liberty Oil & Gas Co., Inc. | | Oil Operator | Feb 1991 |
| 2666 | Liberty Oil And Gas Corp. | Olney, IL 62450-2489-2489 | Oil & Gas Operator | Dec 2021 |
| 2667 | Liberty Operating Company,LLC | | Oil & Gas Operator | Jan 2025 |
| 2668 | Liberty Resources, Inc. | | Oil & Gas Operator | Dec 2024 |
| 2669 | Lighthouse Operating, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Jun 2021 |
| 2670 | Lightning Productions, Inc. | | Oil & Gas Operator | Mar 1990 |
| 2671 | Lignum Oil Company | | Oil & Gas Operator | Dec 1989 |
| 2672 | Limited Resources | Perryton, TX 79070 | Oil & Gas Operator | Aug 2003 |
| 2673 | Lindenmuth & Associates | | Oil & Gas Operator | Aug 2001 |
| 2674 | Linder Energy/La General Oil | | Oil & Gas Operator | Mar 1989 |
| 2675 | Linder Oil Company | | Oil & Gas Operator | Apr 1985 |
| 2676 | Linder Oil Company,A Partnership | Shreveport, LA 71136 | Oil & Gas Operator | Apr 2025 |
| 2677 | Linn Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 2678 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 2679 | Linville Natural Gas Co. Inc. | | Gas Operator | Sep 2000 |
| 2680 | Little & Whyte Operating, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Mar 2008 |
| 2681 | Littlefield Oil & Gas Company | | Oil & Gas Operator | Jan 1990 |
| 2682 | Live Oak Energy, Inc. | | Oil & Gas Operator | Dec 2011 |
| 2683 | Live Oak Petroleum, Inc. | Dallas, TX 75251 | Gas Operator | Mar 2001 |
| 2684 | Lko Operating LLC | | Oil & Gas Operator | Feb 2017 |
| 2685 | LL&N Oil & Gas Co., Inc. | | Oil Operator | Sep 1982 |
| 2686 | Llog Expl. Co. | Metairie, LA 70005 | Oil & Gas Operator | Jan 2003 |
| 2687 | Llog Expl. Co.-Biggs | | Oil Operator | Sep 1985 |
| 2688 | Llog Exploration & Prod Co | | Oil & Gas Operator | Jul 2000 |
| 2689 | Llog Exploration Company, L.L.C. | | Oil & Gas Operator | Jan 2025 |
| 2690 | Llog Production Company | Metairie, LA 70005 | Oil & Gas Operator | Apr 1995 |
| 2691 | Llox, L.L.C. | Covington, LA 70433 | Oil & Gas Operator | Apr 2025 |
| 2692 | Lloyd E. Hargrove | | Oil & Gas Operator | Aug 1998 |
| 2693 | Lloyd M McKenzie | | Oil Operator | Mar 2001 |
| 2694 | LNG Gathering Company | | Oil Operator | Oct 2024 |
| 2695 | Lobo Operating, Inc. | Houston, TX 77077 | Oil & Gas Operator | Dec 2024 |
| 2696 | Lock Arbor Production Co | | Gas Operator | Aug 1987 |
| 2697 | Locust Ridge Gas Company | | Oil Operator | Mar 2003 |
| 2698 | Loe Oil & Gas Corporation | | Gas Operator | Dec 1977 |
| 2699 | Loe Pipe Yard, Inc. | | Oil & Gas Operator | Jan 1997 |
| 2700 | Logue And Patterson, Inc. | | Oil & Gas Operator | Nov 1991 |