| 2501 | Lahoma Gas Company | | Gas Operator | Dec 1980 |
| 2502 | Lahoma Operating, Inc. | | Oil & Gas Operator | Feb 2024 |
| 2503 | Lake A, LTD. | | Oil Operator | May 1998 |
| 2504 | Lake Racourci Gath Sys, LLC | | Oil Operator | May 2004 |
| 2505 | Lake Ronel Oil Company | Tyler, TX 75710 | Oil & Gas Operator | Nov 2019 |
| 2506 | Lakeshore Petroleum Corp. | | Oil & Gas Operator | Dec 1992 |
| 2507 | Lakeside Resources | | Oil & Gas Operator | Mar 1989 |
| 2508 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Dec 2023 |
| 2509 | Lamar Hunt | | Oil & Gas Operator | Oct 2003 |
| 2510 | Lamar Hunt Trust Est Etal | | Oil & Gas Operator | Aug 1996 |
| 2511 | Lamar Hunt Trust Est. | | Oil & Gas Operator | Mar 1978 |
| 2512 | Lamar Matlock | | Oil Operator | Jan 2024 |
| 2513 | Lamar Oil & Gas, Inc. | Rockport, TX 78381 | Oil & Gas Operator | Apr 2024 |
| 2514 | Lamar Smith | | Oil Operator | Aug 1991 |
| 2515 | Lamson Petroleum Corporation | | Oil & Gas Operator | Mar 1993 |
| 2516 | Lamson/Crocker Petroleum Corp. | | Oil & Gas Operator | May 1988 |
| 2517 | Lamson/Onshore Petroleum Corp. | | Oil & Gas Operator | Sep 1985 |
| 2518 | Lance Gas & Oil Productions | | Oil & Gas Operator | Jan 2024 |
| 2519 | Lancer Resources Company | | Oil & Gas Operator | Jan 1998 |
| 2520 | Land & Natural Res. Dev., Inc. | | Oil & Gas Operator | Apr 2007 |
| 2521 | Landmark Venture Group No. 1, Inc. | | Oil & Gas Operator | Dec 2023 |
| 2522 | Landmark Venture Group, Inc. | | Oil Operator | Dec 2008 |
| 2523 | Lanford Drilling Co., Inc. | | Oil Operator | Jun 1996 |
| 2524 | Lankford & Nance | | Gas Operator | Dec 2010 |
| 2525 | Lanmarc Resources | | Oil Operator | Dec 2003 |
| 2526 | Lanoco, Inc. | | Oil & Gas Operator | Sep 2002 |
| 2527 | Lapis Operating, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jul 2015 |
| 2528 | Largo Oil Company | Longview, TX 75606 | Oil & Gas Operator | Apr 2024 |
| 2529 | Lark Production, Inc. | | Oil & Gas Operator | Mar 2023 |
| 2530 | Las Services, Inc. | | Oil & Gas Operator | Oct 1997 |
| 2531 | Laser Gas Company I, LLC | | Oil Operator | Aug 2007 |
| 2532 | Lasmo Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2011 |
| 2533 | Laster Welding And Well Serv, Inc. | | Gas Operator | Jul 2020 |
| 2534 | Lastrada Oil And Gas LTD | | Oil & Gas Operator | May 1992 |
| 2535 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 2536 | Latexo Oil & Gas Co. | | Oil Operator | Sep 1986 |
| 2537 | Latham & Bonner | | Oil Operator | Aug 1987 |
| 2538 | Latham Exploration Company Inc | | Oil & Gas Operator | Aug 1992 |
| 2539 | Latham Production & Service Co | | Oil Operator | Jul 1989 |
| 2540 | Latham, Bonner & Hall | | Oil Operator | Mar 1988 |
| 2541 | Laurel Operating Company, Inc. | Stillwater, OK 74074-3025 | Oil & Gas Operator | Dec 2023 |
| 2542 | Lavaca River Operating Co., LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Apr 2024 |
| 2543 | Lavino Oil And Gas Company | | Oil & Gas Operator | Aug 1989 |
| 2544 | Lawson Engineering, Inc. | | Oil & Gas Operator | Dec 1984 |
| 2545 | Lax, Inc. | | Oil & Gas Operator | Nov 1987 |
| 2546 | Layline Petroleum I, LLC | Houston, TX 77024 | Oil & Gas Operator | May 2013 |
| 2547 | Layton Energy Inc. | Houston, TX 77027 | Oil & Gas Operator | Apr 2024 |
| 2548 | Layton Oil Co. | | Oil Operator | Feb 1994 |
| 2549 | Lea Exploration, Inc. | | Oil & Gas Operator | Nov 1989 |
| 2550 | Leads Resources, L.L.C. | | Oil & Gas Operator | Jan 2017 |
| 2551 | Lear Gas Transmission | | Oil Operator | Aug 1989 |
| 2552 | Lear Petroleum Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Aug 1999 |
| 2553 | Leatherman Creek, Inc. | | Oil Operator | Jul 2001 |
| 2554 | Lebus Oilfield Service Co | | Oil Operator | Sep 2009 |
| 2555 | Lee Mills | | Oil Operator | Feb 1992 |
| 2556 | Lee Roy Daigle | | Oil Operator | Dec 1992 |
| 2557 | Leeward Operators LLC | | Oil & Gas Operator | Jul 2011 |
| 2558 | Legacy Energy LLC | Russell, KS 67665 | Oil Operator | Jan 2024 |
| 2559 | Legacy Operating Company | | Oil & Gas Operator | Aug 1992 |
| 2560 | Legacy Resources Co., L.P. | Indianapolis, IN 46214 | Oil & Gas Operator | Apr 2019 |
| 2561 | Legend Fund, LLC | | Oil & Gas Operator | Dec 2023 |
| 2562 | Legendary Oil Co., Inc. | | Oil Operator | Feb 2004 |
| 2563 | Legendary Well Service, Inc. | | Oil Operator | Jan 1996 |
| 2564 | Leger Production Company, Inc. | | Oil & Gas Operator | Apr 1984 |
| 2565 | Leggett Petroleum, L.L.C. | | Oil & Gas Operator | Dec 2020 |
| 2566 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 2567 | Lenape Resources Corp | | Oil & Gas Operator | Dec 2000 |
| 2568 | Lenert & Pettitt, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 1994 |
| 2569 | Leo Vesenmeir, Jr. | | Oil & Gas Operator | Jul 1987 |
| 2570 | Leo Windham | | Oil Operator | Jul 1992 |
| 2571 | Leroy W. James | | Oil & Gas Operator | Oct 1991 |
| 2572 | Leshen Energy USA LLC | | Oil Operator | Jan 2024 |
| 2573 | Levinson Partners Corporation | Denver, CO 80202 | Oil & Gas Operator | Jul 1995 |
| 2574 | Lewis & Manziel | | Oil Operator | Apr 1989 |
| 2575 | Lewis Operating Company | Holliday, TX 76366 | Oil & Gas Operator | Apr 2024 |
| 2576 | Lewis Williams | | Oil & Gas Operator | Feb 1991 |
| 2577 | Lexico Exploration | | Oil Operator | Mar 1986 |
| 2578 | LGS Exploration Program | | Gas Operator | Jul 1990 |
| 2579 | LGS Exploration, Inc. | | Oil & Gas Operator | Jan 1991 |
| 2580 | LHC Petroleum Corporation | | Oil & Gas Operator | Jul 2001 |
| 2581 | Li'L Sugar Oil Company | | Oil Operator | Nov 2019 |
| 2582 | Liberty Exploration Co. | | Oil Operator | Apr 1987 |
| 2583 | Liberty Oil & Gas Co., Inc. | | Oil Operator | Feb 1991 |
| 2584 | Liberty Oil And Gas Corp. | Olney, IL 62450-2489-2489 | Oil & Gas Operator | Dec 2021 |
| 2585 | Liberty Operating Company,LLC | | Oil & Gas Operator | Jan 2024 |
| 2586 | Liberty Resources, Inc. | | Oil & Gas Operator | Dec 2023 |
| 2587 | Lighthouse Operating, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Jun 2021 |
| 2588 | Lightning Productions, Inc. | | Oil & Gas Operator | Mar 1990 |
| 2589 | Lignum Oil Company | | Oil & Gas Operator | Dec 1989 |
| 2590 | Limited Resources | Perryton, TX 79070 | Oil & Gas Operator | Aug 2003 |
| 2591 | Lindenmuth & Associates | | Oil & Gas Operator | Aug 2001 |
| 2592 | Linder Energy/La General Oil | | Oil & Gas Operator | Mar 1989 |
| 2593 | Linder Oil Company | | Oil & Gas Operator | Apr 1985 |
| 2594 | Linder Oil Company,A Partnership | Shreveport, LA 71136 | Oil & Gas Operator | Apr 2024 |
| 2595 | Linn Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 2596 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 2597 | Linville Natural Gas Co. Inc. | | Gas Operator | Sep 2000 |
| 2598 | Little & Whyte Operating, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Mar 2008 |
| 2599 | Littlefield Oil & Gas Company | | Oil & Gas Operator | Jan 1990 |
| 2600 | Live Oak Energy, Inc | | Oil & Gas Operator | Aug 2021 |