| 1 | E2 Operating LLC | Tulsa, OK 74135 | Oil & Gas Operator | Apr 2025 |
| 2 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Apr 2025 |
| 3 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Jan 2025 |
| 4 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 5 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Feb 2025 |
| 6 | Elder & Vaughn Inc | Oklahoma City, OK 73154-0938 | Oil & Gas Operator | Mar 2008 |
| 7 | Elite Resources Inc | Cleveland, OK 74020 | Oil & Gas Operator | Feb 2025 |
| 8 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Feb 2025 |
| 9 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 10 | Encino Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Apr 2025 |
| 11 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Feb 2025 |
| 12 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 13 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 14 | Enogex Services Corporation | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Apr 2009 |
| 15 | Ensource Inc | Midland, TX 79705 | Oil & Gas Operator | Aug 1998 |
| 16 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 17 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 18 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | May 2022 |
| 19 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Jan 2025 |
| 20 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 21 | Export Petroleum Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Apr 2025 |
| 22 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Apr 2025 |
| 23 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Dec 2024 |