| 1 | Palace Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2009 |
| 2 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 3 | Parker & Parsley Producing L.P. | Midland, TX 79702 | Oil & Gas Operator | Oct 1997 |
| 4 | Pegasus Operating, Inc. | Coldspring, TX 77331 | Oil & Gas Operator | Oct 2025 |
| 5 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 6 | Penn VIrginia Oil & Gas, L.P. | Houston, TX 77084 | Oil & Gas Operator | Nov 2022 |
| 7 | Petro-Guard Company, Inc. | Houston, TX 77057 | Oil & Gas Operator | Nov 2014 |
| 8 | Petro-Guard Production,L.L.C. | Houston, TX 77063 | Oil & Gas Operator | Dec 2024 |
| 9 | Petrogen, Incorporated | Katy, TX 77450 | Oil & Gas Operator | Jan 2012 |
| 10 | Petrogulf Corporation | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 11 | Petroleum Management, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Oct 2025 |
| 12 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 13 | PG&E Resources Offshore Company | Dallas, TX 75206 | Oil & Gas Operator | Oct 1994 |
| 14 | Phillips Energy, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2018 |
| 15 | Pi Energy, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Oct 2025 |
| 16 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 17 | Pioneer Resources Producing, L.P | Irving, TX 75039 | Oil & Gas Operator | Feb 2001 |
| 18 | Pitco Investments, LTD. | Scottsdale, AZ 85261 | Oil & Gas Operator | Jan 2013 |
| 19 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2025 |
| 20 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 21 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 22 | Progenies Operating LLC | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 23 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Oct 2025 |