| 1 | 3-T Exploration, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 2 | Americus Resources, Inc. | | Oil & Gas Operator | Feb 1993 |
| 3 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 4 | Arkla Exploration Co. | Shreveport, LA 71151 | Oil & Gas Operator | Jan 1993 |
| 5 | Australis TMS Inc. | | Oil & Gas Operator | Jun 2025 |
| 6 | Bob Bertolet | | Oil & Gas Operator | Dec 2001 |
| 7 | BP America Production Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2025 |
| 8 | Bridwell Oil Management, LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 9 | Bridwell Oil MGMT Of Al, LLC | | Oil & Gas Operator | Apr 2006 |
| 10 | Britlind Oil LLC | | Oil & Gas Operator | Dec 2020 |
| 11 | Calpine Natural Gas Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2002 |
| 12 | Calpine Natural Gas Company L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 13 | Calpine Natural Gas L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2006 |
| 14 | Clovelly Oil Co., Inc. | | Oil & Gas Operator | Nov 2008 |
| 15 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 16 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 17 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Oct 2025 |
| 18 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 19 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 20 | Encore Operating Louisiana, LLC | | Oil & Gas Operator | Dec 2010 |
| 21 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 22 | Exchange Oil & Gas Company | | Oil & Gas Operator | Oct 1996 |
| 23 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 24 | Grand Gulf Production, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Dec 1997 |
| 25 | Griffin & Griffin Expl, LLC | | Oil & Gas Operator | Jul 2025 |
| 26 | Griffin & Griffin Oil Co. Inc. | | Oil & Gas Operator | Jun 2001 |
| 27 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 28 | KFG Petroleum Corporation | | Oil & Gas Operator | Jul 2025 |
| 29 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | Jul 2025 |
| 30 | Meason Operating Company | Natchez, MS 39121 | Oil & Gas Operator | Dec 2011 |
| 31 | Orx Resources, L.L.C. | Houston, TX 77067 | Oil & Gas Operator | Oct 2025 |
| 32 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 33 | Paloma Natural Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 34 | Perna Oil & Gas LLC | | Oil & Gas Operator | Nov 2024 |
| 35 | Petro-Hunt Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2003 |
| 36 | Pompano Resource Operator LLC | | Oil & Gas Operator | Jun 2025 |
| 37 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 38 | Sheridan Energy,Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2000 |
| 39 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Oct 2025 |
| 40 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 41 | Texaco Producing Inc. | Rock Springs, WY 82901 | Oil & Gas Operator | Dec 2000 |
| 42 | Transcontinental Gas P/L Corp. | | Oil & Gas Operator | Dec 2009 |
| 43 | Transcontinental Gas Pipeline Co LLC | | Oil Operator | Jan 2025 |
| 44 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Oct 2025 |
| 45 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 46 | Vaquero Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |