| 1 | E. T. S. Enterprises, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Jul 1996 |
| 2 | Eagle Exploration Co., Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Dec 2019 |
| 3 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 4 | Eagle Rock Mid-Continent Op, LLC | Houston, TX 77252 | Oil & Gas Operator | Sep 2015 |
| 5 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 6 | Ehvi Exploration LLC | Denver, CO 80202 | Oil & Gas Operator | May 2025 |
| 7 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 8 | Empire Operating, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2017 |
| 9 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 10 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | May 2025 |
| 11 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 12 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 13 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 14 | Energy Transfer Fuel, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 15 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 16 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 17 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 18 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 19 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 20 | Eqv Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Oct 2025 |
| 21 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 22 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 23 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |