| 1 | T & T Production Co. | Victoria, TX 77902 | Oil & Gas Operator | Feb 1995 |
| 2 | Tandem Energy Corporation | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 3 | TC3 Energy Services Company | Bryan, TX 77805 | Oil & Gas Operator | Jan 2005 |
| 4 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 5 | Te-Ray Resources, Inc. | Oklahoma City, OK 73108 | Oil & Gas Operator | Mar 2015 |
| 6 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Oct 2025 |
| 7 | Tekna Synergy Corporation | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 8 | Tempo Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 9 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Oct 2025 |
| 10 | Texakoma Oil & Gas Corp | Dallas, TX 75240 | Oil & Gas Operator | Sep 2014 |
| 11 | Texas Onshore Energy, Inc. | Austin, TX 78704 | Oil & Gas Operator | Oct 2025 |
| 12 | Texas Petroleum Investment Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 13 | Texas Refining, Inc. | Houston, TX 77057 | Oil & Gas Operator | Aug 2003 |
| 14 | Texas Royalty Corp. | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 15 | Texas State Oil Co. | Irving, TX 75062 | Oil & Gas Operator | Mar 2017 |
| 16 | Texcal Energy (GP) LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2016 |
| 17 | Texron Operating, LLC | Bulverde, TX 78163 | Oil & Gas Operator | Oct 2025 |
| 18 | Torch Energy Services, Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2011 |
| 19 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 20 | Tower Resources Inc | Conroe, TX 77304 | Oil & Gas Operator | Oct 2025 |
| 21 | Trailblazer Energy Resources, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 22 | Trestle Creek Properties, LLC | Manchaca, TX 78652 | Oil & Gas Operator | Oct 2025 |
| 23 | Tri-Union Development Corp. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 24 | Tripp Oil Company Inc | Houston, TX 77023 | Oil & Gas Operator | Jan 1992 |
| 25 | Tularosa Operating Company | Kerrville, TX 78029 | Oil & Gas Operator | Mar 2024 |
| 26 | Twojo, Inc. | Longview, TX 75601 | Oil & Gas Operator | Nov 1996 |