| 1 | 31 Operating LLC | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 2 | 4J Well Service, Inc | | Oil Operator | Nov 2025 |
| 3 | Abraxas Petroleum Corporation | San Antonio, TX 78259 | Oil & Gas Operator | Dec 2025 |
| 4 | Acp Energy Corporation | | Oil & Gas Operator | Nov 2025 |
| 5 | Aeon Energy Corp. | | Oil & Gas Operator | Dec 2025 |
| 6 | Agate Petroleum, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Mar 2015 |
| 7 | Albritton Resources Inc | Dallas, TX 75206 | Oil & Gas Operator | Feb 2001 |
| 8 | Alpar Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jul 2011 |
| 9 | Alturas Energy, LLC | Sidney, MT 59270 | Oil Operator | Mar 2022 |
| 10 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 11 | American Eagle Energy Corporation | | Oil & Gas Operator | Oct 2015 |
| 12 | American Oil & Gas, Inc. | | Oil & Gas Operator | Nov 2010 |
| 13 | Amoco Production Company | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 14 | Anadarko Production Co. | | Oil Operator | Feb 1989 |
| 15 | Anr Production Company | Houston, TX 77046 | Oil & Gas Operator | Aug 2017 |
| 16 | Ansbro Petroleum Company, LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2008 |
| 17 | Anschutz Drilling Co. | | Oil Operator | Jul 1961 |
| 18 | Anschutz Exploration Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2025 |
| 19 | Anschutz Oil Co. | | Oil & Gas Operator | Jul 1984 |
| 20 | Anschutz Oil Company LLC | Denver, CO 80202 | Oil & Gas Operator | Sep 2020 |
| 21 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2025 |
| 22 | Apex Energy, L.L.C. | Tulsa, OK 74114 | Oil & Gas Operator | Sep 2025 |
| 23 | Armstrong Operating, Inc. | Dickinson, ND 58602 | Oil & Gas Operator | Nov 2025 |
| 24 | Arrowhead Exploration Company | Olney, TX 76374 | Oil Operator | Dec 1995 |
| 25 | Arsenal Energy USA Inc. | | Oil & Gas Operator | Aug 2016 |
| 26 | Axem Resources Inc | Denver, CO 80202-4617 | Oil & Gas Operator | Jul 2013 |
| 27 | B & B Oilfield Services Inc | Windham, OH 44288 | Oil & Gas Operator | Dec 2024 |
| 28 | B. D. Evans Oil Co. | | Oil & Gas Operator | Jun 2017 |
| 29 | Bakken Hunter, LLC | | Oil & Gas Operator | Jun 2017 |
| 30 | Ballantyne Oil | | Oil & Gas Operator | Jul 2010 |
| 31 | Ballantyne Oil, LLC | | Oil & Gas Operator | Mar 2023 |
| 32 | Ballard Petroleum Holdings LLC | Billings, MT 59104 | Oil & Gas Operator | Nov 2025 |
| 33 | Barbara Fasken | Midland, TX 79701 | Oil & Gas Operator | Dec 1995 |
| 34 | Barron Kidd-Great American Exploration | | Oil Operator | Dec 1968 |
| 35 | Basic Earth Science Systems, Inc. | Austin, TX 78714 | Oil & Gas Operator | Apr 2010 |
| 36 | Baytex Energy USA LLC | Denver, CO 80202 | Oil & Gas Operator | Nov 2014 |
| 37 | Baytex Energy USA LTD | | Oil & Gas Operator | Sep 2014 |
| 38 | Beartooth Oil & Gas Company | Billings, MT 59103 | Oil & Gas Operator | Nov 2025 |
| 39 | Behm Energy, Inc. | Minot, ND 58702 | Oil & Gas Operator | Dec 2025 |
| 40 | Berco Resources LLC | Denver, CO 80206 | Oil & Gas Operator | Sep 2009 |
| 41 | Berco Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Feb 2002 |
| 42 | Berenergy Corporation | Denver, CO 80217 | Oil & Gas Operator | Dec 2025 |
| 43 | Big Sky Well Service, Inc. | | Oil & Gas Operator | Aug 2018 |
| 44 | Bigiron Oil & Gas LLC | | Oil & Gas Operator | Nov 2025 |
| 45 | Bill Barrett Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 46 | Black Hawk Resources, LLC | Bowman, ND 58623 | Oil & Gas Operator | Jun 2011 |
| 47 | Bonray Energy Corp. | | Oil & Gas Operator | Jun 1985 |
| 48 | Bow Petroleum, Inc. Of Colorado | | Oil & Gas Operator | Nov 2025 |
| 49 | Bowers Oil & Gas, Inc. | Grand Junction, CO 81505-1097 | Oil & Gas Operator | Nov 2022 |
| 50 | Bowline Energy LLC | Denver, CO 80201 | Oil & Gas Operator | Dec 2022 |
| 51 | Brent Exploration, Inc. | | Oil & Gas Operator | Apr 1983 |
| 52 | Brigham Oil & Gas, L.P. | Austin, TX 78730 | Oil & Gas Operator | Oct 2015 |
| 53 | Brooks Exploration Inc | Denver, CO 80293 | Oil & Gas Operator | Mar 2001 |
| 54 | Broschat Engineering & Management Services, Inc. | | Oil & Gas Operator | May 2017 |
| 55 | Bruin E&P Operating, LLC | | Oil & Gas Operator | Oct 2021 |
| 56 | Bta Oil Producers | Midland, TX 79701 | Oil & Gas Operator | Sep 2009 |
| 57 | Bta Oil Producers, LLC | Midland, TX 79701 | Oil & Gas Operator | Dec 2025 |
| 58 | Burlington Resources Oil & Gas Company LP | Houston, TX 77252 | Oil & Gas Operator | Dec 2025 |
| 59 | Burlington Resources Oil And Gas Co. | Houston, TX 77210 | Oil & Gas Operator | Mar 2023 |
| 60 | Burnett Energy Inc. | | Oil & Gas Operator | Nov 2025 |
| 61 | Burnett Oil Co Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 62 | Bwab Incorporated | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |
| 63 | C12 Energy: North Dakota LLC | | Oil Operator | Apr 2017 |
| 64 | Calvert Drilling Co. | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 1992 |
| 65 | Calvert Exploration Co | | Oil & Gas Operator | Apr 1993 |
| 66 | Camwest II LP | McKinney, TX 75070 | Oil & Gas Operator | Jul 2007 |
| 67 | Cardinal & Great Plains & Kaufman | | Oil Operator | Apr 1985 |
| 68 | Cardinal Drilling Co. | | Oil Operator | Jan 2007 |
| 69 | Cardinal Petroleum Co. | | Oil & Gas Operator | May 2004 |
| 70 | Carlson Oil Inc. | | Oil & Gas Operator | Oct 2008 |
| 71 | Caroline Hunt Trust Estate | | Oil & Gas Operator | Mar 1987 |
| 72 | Cenex | | Oil & Gas Operator | Dec 1996 |
| 73 | Chaco Energy Company | Denver, CO 80201 | Oil & Gas Operator | Nov 2025 |
| 74 | Challenger Point Energy, LLC | | Oil & Gas Operator | Nov 2025 |
| 75 | Champlin Petroleum Co. | Rock Springs, WY 82902 | Oil & Gas Operator | Mar 1991 |
| 76 | Chandler & Associates, Inc. | Denver, CO 80202 | Oil & Gas Operator | May 1997 |
| 77 | Chandler Energy LLC | Denver, CO 80202 | Oil & Gas Operator | Jan 2009 |
| 78 | Chaparral Energy, Inc. | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2009 |
| 79 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Dec 2025 |
| 80 | Charger Resources, LLC | Hurst, TX 76054 | Oil & Gas Operator | Aug 2015 |
| 81 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Sep 2025 |
| 82 | Christmann Energy Corp. | | Oil & Gas Operator | Feb 1991 |
| 83 | Cirque Resources LP | Denver, CO 80202 | Oil & Gas Operator | Aug 2016 |
| 84 | Citation Oil & Gas Corp | Houston, TX 77269 | Oil & Gas Operator | Dec 2025 |
| 85 | Clearly Petroleum, LLC | Houston, TX 77086 | Oil & Gas Operator | Jun 2020 |
| 86 | Cline Production Company | Billings, MT 59104 | Oil & Gas Operator | Oct 2025 |
| 87 | Clinton Oil Company | Wichita, KS 67202 | Oil & Gas Operator | Apr 1980 |
| 88 | Clyde G. Kissinger | | Oil Operator | Jun 1964 |
| 89 | Clyde W. Jones | | Oil Operator | Sep 2003 |
| 90 | Coastal Oil & Gas Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 91 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2025 |
| 92 | Columbus Energy Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Mar 2008 |
| 93 | Columbus Production Inc | | Oil & Gas Operator | Mar 2005 |
| 94 | Condor Petroleum, Inc. | Denver, CO 80202 | Oil & Gas Operator | Jun 2019 |
| 95 | Conoco Inc | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 96 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Dec 2025 |
| 97 | Consolidated Oil & Gas Inc | Wichita, KS 67202 | Oil & Gas Operator | Dec 2012 |
| 98 | Continental Oil Co. | Durango, CO 81301 | Oil & Gas Operator | Dec 1983 |
| 99 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 100 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Dec 2025 |