| 1 | E R Operating Company | Dallas, TX 75225 | Oil & Gas Operator | Jan 2025 |
| 2 | E2 Operating LLC | Tulsa, OK 74135 | Oil & Gas Operator | Jul 2025 |
| 3 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Apr 2025 |
| 4 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2025 |
| 5 | Edinger Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2007 |
| 6 | Ehrlich, Mitchell | Perryton, TX 79070 | Oil & Gas Operator | May 1999 |
| 7 | Ekg Operating Inc | Seminole, OK 74818-1028 | Oil & Gas Operator | Nov 2015 |
| 8 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 9 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | May 2025 |
| 10 | Elder & Vaughn Inc | Oklahoma City, OK 73154-0938 | Oil & Gas Operator | Mar 2008 |
| 11 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Apr 2025 |
| 12 | Elvera Stiles Trust | Broken Arrow, OK 74011 | Oil & Gas Operator | Apr 2025 |
| 13 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 14 | Encino Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Jul 2025 |
| 15 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | May 2025 |
| 16 | Energon Oil, Inc. | Amarillo, TX 79114 | Oil & Gas Operator | Jul 2025 |
| 17 | Energy Production Services LLC | Oklahoma City, OK 73162-4736 | Oil & Gas Operator | Apr 2020 |
| 18 | Energyquest II, LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Apr 2025 |
| 19 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 20 | Enex Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 21 | Enexco, Inc. | Dallas, TX 75243 | Oil & Gas Operator | Mar 2017 |
| 22 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 23 | Ensource Inc | Midland, TX 79705 | Oil & Gas Operator | Aug 1998 |
| 24 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 25 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 26 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 27 | Eott Energy Operating LP | Houston, TX 77210-4666 | Oil & Gas Operator | Oct 2009 |
| 28 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | Jan 2023 |
| 29 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Apr 2025 |
| 30 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 31 | Esperanza Energy Corp. | Prosper, TX 75078 | Oil & Gas Operator | Mar 2015 |
| 32 | Ew Carter Oil Co;Inc | | Oil & Gas Operator | Apr 2025 |
| 33 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Apr 2025 |
| 34 | Export Petroleum Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Jul 2025 |
| 35 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 36 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | May 2025 |