| 101 | Savant Energy Corporation | | Oil & Gas Operator | Mar 2012 |
| 102 | Scorpion Oil & Gas, LLC | Houston, TX 77036 | Oil & Gas Operator | May 2025 |
| 103 | Secan Oil Co., Inc. | | Oil & Gas Operator | May 1987 |
| 104 | Sensor Oil & Gas Inc | Duncan, OK 73534 | Oil & Gas Operator | May 2013 |
| 105 | Sevarg Company, Inc. | | Oil & Gas Operator | Feb 2016 |
| 106 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 107 | Signal, LLC Of Mississippi | | Oil & Gas Operator | Dec 2024 |
| 108 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 109 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 110 | Sonoran Energy Inc. | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 111 | Southwind Oil & Gas LLC | | Oil & Gas Operator | Dec 2023 |
| 112 | Sun Exploration-Production Co. | | Oil & Gas Operator | Jan 1990 |
| 113 | Sun Texas Company | | Oil & Gas Operator | Jun 1981 |
| 114 | Sunburst, Inc. | Wheat Ridge, CO 80033 | Oil & Gas Operator | Jul 2025 |
| 115 | Sunex Resources Incorporated | | Oil Operator | Dec 1981 |
| 116 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 117 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |
| 118 | T. C. Morrow Oil Co. | | Oil & Gas Operator | Apr 1991 |
| 119 | T. J. Operating Co., Inc. | | Oil & Gas Operator | Aug 1998 |
| 120 | Tennessee Gas Pipeline Company | | Oil & Gas Operator | Dec 2011 |
| 121 | Texas Gas Transmission Corp. | | Oil Operator | Aug 2003 |
| 122 | Texas Gas Transmission LLC | Owensboro, KY 42301 | Oil & Gas Operator | Dec 2024 |
| 123 | Texas Pacific Oil Company Inc. | | Oil & Gas Operator | Dec 1980 |
| 124 | Texas T Oil Co. | | Oil & Gas Operator | Apr 1990 |
| 125 | Transcontinental Oil Corp. | | Oil & Gas Operator | Sep 1985 |
| 126 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 127 | Verado Energy, Inc. | Allen, TX 75013 | Oil & Gas Operator | Oct 2025 |
| 128 | Vision Natural Res-La, LLC | | Oil Operator | Dec 2024 |
| 129 | W. D. Tarver | | Oil Operator | Aug 2005 |
| 130 | Westar Oil & Minerals | | Oil Operator | Feb 1999 |
| 131 | Whitton Company, Inc. | | Oil & Gas Operator | Jul 2020 |
| 132 | Wilcobill Corporation | | Oil Operator | Dec 1986 |
| 133 | Wildcat Well Services, LTD. | | Oil Operator | Oct 1989 |
| 134 | Windrush Operating Co., L.L.C. | Longville, LA 70652 | Oil & Gas Operator | Oct 2025 |
| 135 | Windrush Operating Company | | Oil & Gas Operator | Jan 2009 |
| 136 | Witt Oil Production, Inc. | | Oil & Gas Operator | Nov 1984 |
| 137 | Yuma E & P Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |