| 1 | Panaco Production Co | Houston, TX 77002 | Oil & Gas Operator | Dec 1999 |
| 2 | Panaco, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |
| 3 | Papco, Inc. | Warren, PA 16365 | Oil & Gas Operator | Oct 2025 |
| 4 | Par Minerals Corporation | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 5 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 6 | Parker & Parsley Producing L.P. | Midland, TX 79702 | Oil & Gas Operator | Oct 1997 |
| 7 | Patrick Pet. Corp. Of Michigan | Houston, TX 77227 | Oil & Gas Operator | Aug 1995 |
| 8 | Patriot Operating Company, Inc. | Houston, TX 77008 | Oil & Gas Operator | Sep 2003 |
| 9 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 10 | Penn VIrginia Oil & Gas, L.P. | Houston, TX 77084 | Oil & Gas Operator | Nov 2022 |
| 11 | Peoples Energy Prod.-TX, L.P. | Houston, TX 77002 | Oil & Gas Operator | Sep 2007 |
| 12 | Permian Natural Resources | Pflugerville, TX 78660 | Oil & Gas Operator | Oct 2025 |
| 13 | Petro Vest, Inc. | Houston, TX 77046 | Oil & Gas Operator | Sep 2014 |
| 14 | Petrocorp Incorporated,A TX.Corp | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2005 |
| 15 | Petrodome Operating, LLC | Houston, TX 77265 | Oil & Gas Operator | Jun 2025 |
| 16 | Petrogas Energy Services, LLC | Dallas, TX 75214 | Oil Operator | Oct 2025 |
| 17 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 18 | Petroleum Capital, L.C. | Dallas, TX 75367 | Oil & Gas Operator | Oct 2025 |
| 19 | Petrotex Engineering Company | Cypress, TX 77429 | Oil & Gas Operator | Oct 2025 |
| 20 | Phillips Energy, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2018 |
| 21 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 22 | Phoenix Resources LLC | Longview, TX 75604 | Oil & Gas Operator | Jul 2022 |
| 23 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 24 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 25 | Plains Resources Inc. | Houston, TX 77002 | Oil & Gas Operator | Jul 2008 |
| 26 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 27 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 28 | Poynor Corporation | Beaumont, TX 77706 | Oil & Gas Operator | Oct 2025 |
| 29 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2025 |
| 30 | Prime Natural Resources, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jun 2007 |
| 31 | Progenies Operating LLC | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 32 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Oct 2025 |
| 33 | Proton Energy, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2005 |
| 34 | Puls Operating Company | Boerne, TX 78006 | Oil & Gas Operator | Oct 2025 |
| 35 | Puls, W. L. | Houston, TX 77084 | Oil & Gas Operator | Sep 2002 |
| 36 | Pyramid Exploration | Houston, TX 77241 | Oil & Gas Operator | Sep 1995 |