| 1 | Abraxas Production Corporation | San Antonio, TX 78270 | Oil & Gas Operator | Sep 1999 |
| 2 | Atmos Pipeline - Texas | Dallas, TX 75240 | Oil & Gas Operator | Dec 2024 |
| 3 | Avian Tech International, Inc. | Euless, TX 76040 | Oil & Gas Operator | Apr 1995 |
| 4 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 5 | Electragas, Inc. | Houston, TX 77064 | Oil Operator | Dec 2024 |
| 6 | Ginco Operating Co. | San Antonio, TX 78217 | Oil & Gas Operator | Dec 2024 |
| 7 | Goliad Operating Company | Houston, TX 77265 | Oil & Gas Operator | Aug 2003 |
| 8 | Goode, J. H., Jr. | Lockhart, TX 78644 | Oil & Gas Operator | Apr 1996 |
| 9 | Gulfmark Energy Inc | Houston, TX 77027 | Gas Operator | Apr 2023 |
| 10 | Hollub, Lambert Drilling Company | Seguin, TX 78155 | Oil & Gas Operator | Dec 2024 |
| 11 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Dec 2024 |
| 12 | Kinder Morgan Tejas Pipeline LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 13 | Lynch, W. W. | San Antonio, TX 78205 | Oil & Gas Operator | Jul 2006 |
| 14 | Magna Oil & Gas Corporation | Irving, TX 75017 | Oil & Gas Operator | Feb 2016 |
| 15 | Mueller Engineering Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Feb 2002 |
| 16 | Orisol Oil Co. | Houston, TX 77206 | Oil Operator | Jun 2000 |
| 17 | Penrod Oil Company Of Texas, Inc | Milano, TX 76556 | Oil & Gas Operator | Dec 2024 |
| 18 | Preferred Pipeline Corp. | Victoria, TX 77902 | Oil & Gas Operator | Nov 2024 |
| 19 | R.D. Oil Company | Austin, TX 78755 | Oil & Gas Operator | Dec 2024 |
| 20 | Regal Petroleum Services | Euless, TX 76039 | Oil & Gas Operator | Aug 2002 |
| 21 | Sierra Minerals, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Dec 2024 |
| 22 | Sonora Petroleum Corp. | Austin, TX 78734 | Oil & Gas Operator | Dec 2024 |
| 23 | Thrall Operating Company, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Dec 2024 |
| 24 | Wild Cat Operating Company | Victoria, TX 77903 | Oil & Gas Operator | Mar 2008 |
| 25 | Winchester Energy Operating Co. | Austin, TX 78746 | Oil & Gas Operator | Dec 2024 |