| 1 | L & J Oil | Gainesville, TX 76240 | Oil & Gas Operator | Nov 2000 |
| 2 | L & S Drilling, Inc. | Kamay, TX 76369 | Oil & Gas Operator | Mar 2016 |
| 3 | L And L Production Company | Skellytown, TX 79080 | Oil & Gas Operator | Sep 1996 |
| 4 | L L & M Properties, Inc. | Burkburnett, TX 76354 | Oil & Gas Operator | Aug 2004 |
| 5 | L-Texx Petroleum, LP | Arlington, TX 76013 | Oil & Gas Operator | Oct 2025 |
| 6 | L7 Energy LLC | Wichita Falls, TX 76308 | Oil Operator | Oct 2025 |
| 7 | Lackey, William H. Oil And Gas | Shawnee, OK 74804 | Oil & Gas Operator | Feb 2024 |
| 8 | Landrum Petroleum Co., Inc. | Burkburnett, TX 76354 | Oil Operator | Mar 2008 |
| 9 | Landrum West, Inc. | Burkburnett, TX 76354 | Oil & Gas Operator | Dec 1997 |
| 10 | Larance Engineering Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Jan 1996 |
| 11 | Layline Energy I LLC | Houston, TX 77024 | Oil & Gas Operator | Dec 2019 |
| 12 | LC Operating, LLC | Burkburnett, TX 76354 | Oil & Gas Operator | Oct 2025 |
| 13 | Leading Edge Energy LLC | San Antonio, TX 78205 | Oil Operator | Oct 2025 |
| 14 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 15 | Leonard Brothers Operating Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Oct 2025 |
| 16 | Lewis Operating Company | Holliday, TX 76366 | Oil & Gas Operator | Oct 2025 |
| 17 | Limestone Oil & Gas Co. | Wichita Falls, TX 76302 | Oil & Gas Operator | Jul 2002 |
| 18 | Lincoln Energy Partners, LLC | Graham, TX 76450 | Oil Operator | Oct 2025 |
| 19 | Lindemann, James D. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 20 | Lindemann, W. L., DRLG. Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jun 1994 |
| 21 | Lindemann, W.L., Oper. Co., Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2006 |
| 22 | Little, Quintin Company,Inc.,The | Ardmore, OK 73402 | Oil & Gas Operator | Oct 2025 |
| 23 | LMH Energy | Wichita Falls, TX 76302 | Oil & Gas Operator | Oct 2025 |
| 24 | Lode Holdings, LLC | Wichita Falls, TX 76301 | Oil Operator | Oct 2025 |
| 25 | Loveless Properties | Burkburnett, TX 76354 | Oil & Gas Operator | Apr 2021 |
| 26 | LTS Oil & Gas | Lubbock, TX 79424 | Oil & Gas Operator | Oct 2025 |
| 27 | LTS Oil & Gas A | Lubbock, TX 79424 | Oil & Gas Operator | Oct 2025 |
| 28 | Luke, D.L. Oil Co. | Burkburnett, TX 76354 | Oil & Gas Operator | Oct 2025 |
| 29 | Lunn, Will | Wichita Falls, TX 76301 | Oil & Gas Operator | Jun 1997 |