| 1 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 2 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Jun 2025 |
| 3 | Earlsboro Energies Corporation | Oklahoma City, OK 73116-3605 | Oil & Gas Operator | Jun 2025 |
| 4 | Earthstone Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Jul 2025 |
| 5 | Eason Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2012 |
| 6 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2025 |
| 7 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 8 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 9 | Egolf Operating Company | Oklahoma City, OK 73114-7899 | Oil & Gas Operator | Apr 1998 |
| 10 | El Paso Natural Gas Company | El Paso, TX 79978 | Oil & Gas Operator | Apr 2013 |
| 11 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 12 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Jul 2025 |
| 13 | Elk Oil Company | Overland Park, KS 66212 | Oil & Gas Operator | Sep 2007 |
| 14 | Elm Ridge Exploration Company LLC | Bloomfield, NM 87413 | Oil & Gas Operator | Nov 2017 |
| 15 | Elmore Stanley G | Bartlesville, OK 74006-1741 | Oil & Gas Operator | Sep 2023 |
| 16 | Encana Energy Resources Inc | Denver, CO 80202-2828 | Oil & Gas Operator | Feb 2024 |
| 17 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | May 2025 |
| 18 | Energy Resources Dev Inc | Bixby, OK 74008-3658 | Oil & Gas Operator | Jun 2025 |
| 19 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 20 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 21 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 22 | Esco Exploration, Inc | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 23 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 24 | Excalibur Resources LLC | Houston, TX 77002-5220 | Oil & Gas Operator | Jul 2025 |
| 25 | Excelco Energy Inc. | Kingwood, TX 77339 | Oil & Gas Operator | Jul 2018 |
| 26 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 27 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 28 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Jul 2025 |