| 1 | P & A Well Service | | Oil & Gas Operator | Jan 1994 |
| 2 | P & P Producing Inc | Midland, TX 79702 | Oil & Gas Operator | Feb 2015 |
| 3 | Pacific Enterprises Oil Co USA | Dallas, TX 75201 | Oil & Gas Operator | Feb 2001 |
| 4 | Pacific Enterprises Royalty Co | Oklahoma City, OK 73101 | Oil & Gas Operator | Feb 2002 |
| 5 | Pacific-Atlantic Oil Company, Inc. | | Oil & Gas Operator | Aug 2016 |
| 6 | Palace Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2009 |
| 7 | Pan-Ok Production Company | | Oil & Gas Operator | Dec 2023 |
| 8 | Parker & Parsley Devpt L P | | Oil & Gas Operator | Oct 1997 |
| 9 | Partners Oil Company | Tulsa, OK 74135 | Oil & Gas Operator | Aug 1995 |
| 10 | Patrick Petroleum Corp. | | Oil & Gas Operator | Oct 1984 |
| 11 | Patterson Resources, Inc. | | Oil & Gas Operator | Apr 1984 |
| 12 | Paxton Oil Company | | Oil & Gas Operator | Dec 2023 |
| 13 | Peachtree Production Co. | | Oil & Gas Operator | Mar 1981 |
| 14 | Pecos Western Corporation | | Gas Operator | Feb 1992 |
| 15 | Pel-Tex Oil Company, Inc. | | Oil & Gas Operator | Jul 1995 |
| 16 | Pel-Tex, Inc. | | Oil & Gas Operator | Jul 1985 |
| 17 | Pelican Dome Exploration Inc. | Harahan, LA 70123 | Oil & Gas Operator | Aug 2000 |
| 18 | Pend Oreille Oil & Gas Company | | Oil & Gas Operator | Sep 1989 |
| 19 | Pennzenergy Explor & Prod LLC | | Oil & Gas Operator | Dec 1999 |
| 20 | Pennzoil E & P Co - Clark Oil | | Oil & Gas Operator | Apr 1980 |
| 21 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 22 | Perdido Energy Louisiana, LLC | | Oil & Gas Operator | Dec 2023 |
| 23 | Perenco LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 24 | Petro-Lewis Corp. | | Oil & Gas Operator | Feb 1994 |
| 25 | Petrodome Operating, LLC | Houston, TX 77265 | Oil & Gas Operator | Dec 2023 |
| 26 | Petrogulf Corporation | Denver, CO 80202 | Oil & Gas Operator | Apr 2024 |
| 27 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 28 | Petroleum Properties MGMT Corp | | Oil & Gas Operator | Aug 1990 |
| 29 | Petroquest Energy, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Feb 2001 |
| 30 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | Apr 2024 |
| 31 | Petrus Oil Company., L.P. | | Oil & Gas Operator | Dec 1989 |
| 32 | Petsec Energy Inc. | | Oil & Gas Operator | Sep 2012 |
| 33 | Phalanx Petroleum LLC | | Oil & Gas Operator | Dec 2023 |
| 34 | Phillips Oil Company | Casper, WY 82602 | Oil & Gas Operator | Sep 1986 |
| 35 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 36 | Phoenix Exploration Company LP | | Oil & Gas Operator | Sep 2011 |
| 37 | Pioneer Natural Res. (GPC), Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 1998 |
| 38 | Pioneer Natural Resources USA Inc | Irving, TX 75039 | Oil & Gas Operator | Dec 2023 |
| 39 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 40 | Plymouth Resource Group LLC | | Oil & Gas Operator | Dec 1999 |
| 41 | Plymouth Resources Group II Inc | | Oil & Gas Operator | May 2007 |
| 42 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 43 | Pontchartrain Oil & Gas Corp 2 | | Oil & Gas Operator | Dec 1984 |
| 44 | Precio Energy, LLC | Beaumont, TX 77726 | Oil & Gas Operator | Apr 2024 |
| 45 | Presidio Energy, Inc. | | Oil & Gas Operator | Jan 1992 |
| 46 | Presidio Exploration, Inc. | Englewood, CO 80155 | Oil & Gas Operator | May 1999 |
| 47 | Prime Natural Resources, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jun 2007 |
| 48 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 49 | Prosper Energy Corporation | | Oil & Gas Operator | Oct 1988 |
| 50 | Proven Fuel Exploration, Inc. | | Oil & Gas Operator | Mar 2022 |
| 51 | PXP Gulf Coast Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 52 | PXP Louisiana L.L.C. | | Oil & Gas Operator | Nov 2010 |
| 53 | Pyro Energy Corp | Kingwood, TX 77339-2102 | Oil & Gas Operator | Mar 1998 |