| 1 | P & P Producing Inc | Midland, TX 79702 | Oil & Gas Operator | Feb 2015 |
| 2 | Palace Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2009 |
| 3 | Paladin Petroleum III, L.L.C. | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 4 | Palm Energy Offshore, L.L.C. | | Oil & Gas Operator | Apr 2019 |
| 5 | Pan Petroleum MLP | Kansas City, MO 64114 | Oil & Gas Operator | Aug 1997 |
| 6 | Pan-Ok Production Company | | Oil & Gas Operator | Nov 2024 |
| 7 | Panaco Production Co | Houston, TX 77002 | Oil & Gas Operator | Dec 1999 |
| 8 | Panaco, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2024 |
| 9 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 10 | Parker & Parsley Devpt L P | | Oil & Gas Operator | Oct 1997 |
| 11 | Partners Oil Company | Tulsa, OK 74135 | Oil & Gas Operator | Aug 1995 |
| 12 | Patrick Petroleum Corp. | | Oil & Gas Operator | Oct 1984 |
| 13 | Paxton Oil Company | | Oil & Gas Operator | Dec 2024 |
| 14 | Pel-Tex Oil Company, Inc. | | Oil & Gas Operator | Jul 1995 |
| 15 | Pelto Oil Co | Houston, TX 77002 | Oil & Gas Operator | Nov 1998 |
| 16 | Pend Oreille Oil & Gas Company | | Oil & Gas Operator | Sep 1989 |
| 17 | Pengo Petroleum, Inc. | | Oil & Gas Operator | Dec 2013 |
| 18 | Pengo Petroleum, Inc. & J.W.S. | | Oil & Gas Operator | Jul 1977 |
| 19 | Pengo Producing Company | | Oil & Gas Operator | Mar 1987 |
| 20 | Penn Exploration Corp. | | Gas Operator | Feb 1984 |
| 21 | Pennzenergy Explor & Prod LLC | | Oil & Gas Operator | Dec 1999 |
| 22 | Pennzoil Company | Midland, TX 79710-0090 | Oil & Gas Operator | Mar 2000 |
| 23 | Pennzoil E & P Co Et Al | | Oil & Gas Operator | Feb 1999 |
| 24 | Pennzoil E & P Co-Sohio Et Al | | Oil & Gas Operator | Jun 1991 |
| 25 | Pennzoil E & P Co-Sohio Petr | | Oil & Gas Operator | Feb 1999 |
| 26 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 27 | Pennzoil Petroleum Company | Houston, TX 77252 | Oil & Gas Operator | Nov 1999 |
| 28 | Perdido Energy Louisiana, LLC | | Oil & Gas Operator | Dec 2024 |
| 29 | Petro-Lewis Corp. | | Oil & Gas Operator | Feb 1994 |
| 30 | Petrodome Operating, LLC | Houston, TX 77265 | Oil & Gas Operator | Nov 2024 |
| 31 | Petrohawk Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2005 |
| 32 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 33 | Petroleum Corporation Of Texas | Breckenridge, TX 76024 | Oil & Gas Operator | May 2002 |
| 34 | Petroleum Resource MGMT Co TX | | Oil & Gas Operator | Sep 2020 |
| 35 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | Mar 2025 |
| 36 | Petsec Energy Inc. | | Oil & Gas Operator | Sep 2012 |
| 37 | PG&E Resources Offshore Company | Dallas, TX 75206 | Oil & Gas Operator | Oct 1994 |
| 38 | Phillips Oil Company | Casper, WY 82602 | Oil & Gas Operator | Sep 1986 |
| 39 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 40 | Pinnacle Energy, LLC | | Oil & Gas Operator | Jan 2025 |
| 41 | Pioneer Natural Res. (GPC), Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 1998 |
| 42 | Pioneer Natural Resources USA Inc | Irving, TX 75039 | Oil & Gas Operator | Nov 2024 |
| 43 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 44 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 45 | Poydras Energy Partners, LLC | | Oil & Gas Operator | Dec 2021 |
| 46 | Prairie Producing Company | | Oil & Gas Operator | Dec 1992 |
| 47 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2025 |
| 48 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 49 | Progress Petroleum Co. | | Oil & Gas Operator | Apr 1993 |
| 50 | PXP Gulf Coast Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 51 | PXP Louisiana L.L.C. | | Oil & Gas Operator | Nov 2010 |