| 101 | Serio Oil Corp. | | Oil & Gas Operator | Sep 1991 |
| 102 | Serio Operating Company | | Oil & Gas Operator | Mar 2007 |
| 103 | Shell Oil Company | Houston, TX 77210 | Oil & Gas Operator | Apr 2015 |
| 104 | Sola Operating, LLC | Trout, LA 71371 | Oil Operator | Oct 2025 |
| 105 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 106 | Sooner Corporation | | Oil & Gas Operator | Oct 1990 |
| 107 | Southwest Gas Producing Co Inc | | Oil & Gas Operator | Nov 1994 |
| 108 | Southwest Oil Properties, Inc. | | Oil & Gas Operator | Feb 1996 |
| 109 | Swepi LP | Houston, TX 77079 | Oil & Gas Operator | Jul 2020 |
| 110 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 111 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |
| 112 | Taurus Exploration U.S.A., Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 1998 |
| 113 | Tideway Oil Programs, Inc. | | Oil & Gas Operator | Oct 1980 |
| 114 | Tom Littlepage Oil Properties | | Oil & Gas Operator | Dec 1984 |
| 115 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 116 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 117 | United Gas Pipe Line Co. | | Oil Operator | Aug 1993 |
| 118 | Vega Oil & Gas MGMT., Inc. | | Oil & Gas Operator | Aug 1981 |
| 119 | Verado Energy, Inc. | Allen, TX 75013 | Oil & Gas Operator | Oct 2025 |
| 120 | Vine Energy Operating LP | | Gas Operator | Oct 2021 |
| 121 | Vine Oil & Gas LP | | Gas Operator | Apr 2021 |
| 122 | W. A. Moncrief | | Oil & Gas Operator | Jun 2010 |
| 123 | W. A. Moncrief, Jr. | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 2025 |
| 124 | Westar Oil & Minerals | | Oil Operator | Feb 1999 |
| 125 | White River Operating LLC | Gilmer, TX 75644 | Oil & Gas Operator | Jul 2025 |
| 126 | Wilcox Energy Company | | Oil & Gas Operator | Jul 2025 |
| 127 | Woco La, LLC | | Oil Operator | Jan 2025 |