| 1 | Eagle Energy Production LLC | Tulsa, OK 74136-1935 | Oil & Gas Operator | Mar 2020 |
| 2 | Eagle Exploration Production LLC | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 3 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Jun 2025 |
| 4 | Eagle Rock Mid-Continent Operating LLC | Tulsa, OK 74103-3703 | Oil & Gas Operator | Feb 2025 |
| 5 | Earlsboro Energies Corporation | Oklahoma City, OK 73116-3605 | Oil & Gas Operator | Feb 2025 |
| 6 | Eberly & Meade | Oklahoma City, OK 73118 | Oil & Gas Operator | Jul 2002 |
| 7 | Edinger Engineering, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2025 |
| 8 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 9 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 10 | El Pache Energy Inc | Duncan, OK 73533 | Oil & Gas Operator | Aug 2017 |
| 11 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 12 | Elder & Vaughn Inc | Oklahoma City, OK 73154-0938 | Oil & Gas Operator | Mar 2008 |
| 13 | Elite Tank Trucks, Inc | | Oil & Gas Operator | Mar 2025 |
| 14 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Apr 2025 |
| 15 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 16 | Enernet Inc | Oklahoma City, OK 73102-8004 | Oil & Gas Operator | Nov 2014 |
| 17 | Enersource Royalty Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2013 |
| 18 | Enex Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 19 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 20 | Ensource Inc | Midland, TX 79705 | Oil & Gas Operator | Aug 1998 |
| 21 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 22 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2025 |
| 23 | Eott Energy Corporation | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 1995 |
| 24 | EP Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 25 | Esco Exploration, Inc | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 26 | Esis Inc | | Oil & Gas Operator | Feb 2017 |
| 27 | Excelco Energy Inc. | Kingwood, TX 77339 | Oil & Gas Operator | Jul 2018 |
| 28 | Exok, Inc. | Oklahoma City, OK 73116 | Oil & Gas Operator | Feb 2025 |
| 29 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Jun 2025 |