| 1 | Ea Petroleum Inc | Norman, OK 73072-4147 | Oil & Gas Operator | May 2006 |
| 2 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Jun 2026 |
| 3 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Feb 2026 |
| 4 | Eason Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2012 |
| 5 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2026 |
| 6 | Edinger Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2007 |
| 7 | Eei Operating Inc. | Plano, TX 75093 | Oil & Gas Operator | May 2015 |
| 8 | Elf Aquitaine Inc | Houston, TX 77002 | Oil & Gas Operator | May 1991 |
| 9 | Elite Resources Inc | Cleveland, OK 74020 | Oil & Gas Operator | Mar 2026 |
| 10 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Dec 2025 |
| 11 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Mar 2026 |
| 12 | Endeavor Natural Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2015 |
| 13 | Energex Inc. | Abilene, TX 79604 | Oil & Gas Operator | Jun 2026 |
| 14 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2025 |
| 15 | Energy Production Services LLC | Oklahoma City, OK 73162-4736 | Oil & Gas Operator | Apr 2020 |
| 16 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jun 2026 |
| 17 | Ensource Inc | Midland, TX 79705 | Oil & Gas Operator | Aug 1998 |
| 18 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 19 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 20 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | Jan 2023 |
| 21 | Equal Energy Us Inc | Tulsa, OK 74103-4621 | Oil & Gas Operator | Nov 2019 |
| 22 | Equipment Lott Inc The | Hennessey, OK 73742-0655 | Oil & Gas Operator | Mar 2008 |
| 23 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 24 | Excelco Energy Inc. | Kingwood, TX 77339 | Oil & Gas Operator | Jul 2018 |
| 25 | Exok Inc | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2026 |
| 26 | Exoko Operating Company Inc | Tulsa, OK 74170-0246 | Oil & Gas Operator | Jan 2006 |
| 27 | Exploration Associates II LLC | Oklahoma City, OK 73102-8815 | Oil & Gas Operator | Jan 2013 |
| 28 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Jun 2026 |
| 29 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Mar 2026 |