| 1 | E.G. Operating | Dallas, TX 75206 | Oil & Gas Operator | Mar 2008 |
| 2 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 3 | Eclipse Petroleum Corporation | La Grange, TX 78945 | Oil & Gas Operator | Aug 2003 |
| 4 | Ef Oil And Gas Invest, L.L.C. | Beaver, OK 73932 | Oil Operator | Oct 2025 |
| 5 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 6 | Element Petroleum Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2015 |
| 7 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 8 | Energen Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2021 |
| 9 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 10 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 11 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jun 2025 |
| 12 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 13 | Estacado Energy, Inc. | Austin, TX 78716 | Oil & Gas Operator | Jul 1999 |
| 14 | Estoril Producing Corporation | Midland, TX 79701 | Oil & Gas Operator | Apr 1994 |
| 15 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 16 | Extex Operating Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 17 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 18 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |