| 1 | Aa Production Services Inc. | | Gas Operator | Apr 2025 |
| 2 | Anacapa Oil Corporation | | Gas Operator | Apr 2025 |
| 3 | Arkoma Production Company Of California | | Oil & Gas Operator | Dec 1993 |
| 4 | Aspen Exploration Corporation | | Oil & Gas Operator | Dec 2007 |
| 5 | Atlantic Oil Company | | Oil & Gas Operator | Apr 2025 |
| 6 | Caballero Operations LLC | | Oil & Gas Operator | May 2025 |
| 7 | California Resources Production Corporation | | Oil & Gas Operator | Apr 2025 |
| 8 | Concordia Resources Inc. | | Oil & Gas Operator | May 2025 |
| 9 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 10 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 11 | Dekalb Energy Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 1996 |
| 12 | Depco Inc. | Denver, CO 80202 | Oil & Gas Operator | Apr 2014 |
| 13 | Donald C Slawson Expl Co. Inc | | Oil & Gas Operator | Dec 2020 |
| 14 | Dos Rios Inc. | | Gas Operator | Jun 2025 |
| 15 | Drilling Exploration & Operating Co. Inc. | | Oil & Gas Operator | Apr 2025 |
| 16 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Jul 2025 |
| 17 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 18 | Foothill Energy, LLC | Spring, TX 77393 | Oil & Gas Operator | Jul 2025 |
| 19 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Apr 2025 |
| 20 | Maranatha Petroleum Inc. | | Oil & Gas Operator | Apr 2025 |
| 21 | Mentren Corporation | | Gas Operator | May 2025 |
| 22 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 23 | Monument Production Inc. | | Oil & Gas Operator | Dec 2011 |
| 24 | Nahama & Weagant Energy Company | | Oil & Gas Operator | Dec 1997 |
| 25 | Natural Gas Corp. Of Calif. | | Oil & Gas Operator | Dec 1987 |
| 26 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 27 | North Valley Oil & Gas Co. | | Oil & Gas Operator | Dec 1996 |
| 28 | Northern Energy Devel. Co. | | Gas Operator | Dec 1995 |
| 29 | Northern Michigan Expl Co | | Oil & Gas Operator | Jul 1990 |
| 30 | Oil Securities Inc. | | Gas Operator | Dec 2003 |
| 31 | Paul Graham Drilling & Service Co. | | Oil & Gas Operator | Dec 2011 |
| 32 | Petrogulf Corporation | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 33 | Production Specialties Company | | Oil & Gas Operator | Dec 2003 |
| 34 | Quadren Cryogenic Process LTD. | | Gas Operator | May 2025 |
| 35 | R&R Resources LLC | | Oil & Gas Operator | Apr 2025 |
| 36 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2025 |
| 37 | Santa Fe Minerals | | Gas Operator | Dec 1993 |
| 38 | Seneca Resources Co LLC | Cranberry Township, PA 16066 | Oil & Gas Operator | May 2025 |
| 39 | Seneca Western Minerals Corp. | | Oil & Gas Operator | Dec 2009 |
| 40 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 41 | Signal Hill Petroleum Inc. | | Oil & Gas Operator | May 2025 |
| 42 | T. A. Atkinson Opr. | | Gas Operator | Dec 1997 |
| 43 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Apr 2025 |
| 44 | The Nahabedian Exploration Group LLC | | Oil & Gas Operator | Apr 2025 |
| 45 | TJ Ballantyne Living Trust | | Oil & Gas Operator | Dec 2019 |
| 46 | Towne Exploration Company LP | | Oil & Gas Operator | May 2025 |
| 47 | Tri-Valley Oil & Gas Co. | | Oil & Gas Operator | Apr 2025 |
| 48 | Trio Petroleum LLC | | Oil & Gas Operator | Apr 2025 |
| 49 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 50 | Venada National | | Oil & Gas Operator | Dec 2010 |
| 51 | Venoco LLC | | Oil & Gas Operator | Apr 2025 |
| 52 | Vintage Production California LLC | | Oil & Gas Operator | Jun 2016 |