| 1 | 3 & 1 Operating Inc | | Oil & Gas Operator | Aug 2015 |
| 2 | Acadienergy, Inc. | | Oil & Gas Operator | Jun 1988 |
| 3 | Activa Resources, LLC | San Antonio, TX 78205 | Oil & Gas Operator | Oct 2025 |
| 4 | Addison Resources Inc. | | Oil & Gas Operator | Jul 1998 |
| 5 | Aladdin Energy, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Feb 1999 |
| 6 | Alltex Exploration, Inc. | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 7 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Oct 2025 |
| 8 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 9 | Ambrit Energy Corporation | Garland, TX 75044 | Oil & Gas Operator | Jun 2003 |
| 10 | Aminex USA, Inc. | Somerset, TX 78069 | Oil & Gas Operator | May 2018 |
| 11 | Aminoil USA Inc | | Oil & Gas Operator | Jan 1985 |
| 12 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 13 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Jul 2025 |
| 14 | Anderson Producing, Inc. | Houston, TX 77057 | Oil & Gas Operator | Sep 2013 |
| 15 | Anglo Production Company | | Oil & Gas Operator | Nov 1983 |
| 16 | Annco Pet. Co & Equipment, Inc | | Oil & Gas Operator | Sep 1982 |
| 17 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 18 | Arbol Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Oct 2025 |
| 19 | Arnaudville Company Inc. | | Oil & Gas Operator | Apr 1995 |
| 20 | Artzberger-Johnson | | Oil & Gas Operator | Mar 1978 |
| 21 | Aspect Energy, LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 22 | Aspect Resources LLC | Denver, CO 80202 | Oil & Gas Operator | May 2002 |
| 23 | Auster Oil And Gas, Inc. | | Oil & Gas Operator | Mar 1989 |
| 24 | Auster Oil And Gas, Inc. Et Al | | Oil & Gas Operator | May 2001 |
| 25 | Austral Oil & Exploration, Inc | | Oil & Gas Operator | Jun 2004 |
| 26 | Austral Oil Company Incorporated | Sulphur, LA 70663 | Oil & Gas Operator | Mar 2008 |
| 27 | Azimuth Energy, LLC | Denver, CO 80203 | Oil & Gas Operator | Sep 2006 |
| 28 | Badger Energy LLC | | Oil & Gas Operator | Dec 2024 |
| 29 | Ballard Exploration Company,Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 30 | Belco Development Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Feb 1994 |
| 31 | Belco Petroleum Corp | Grand Junction, CO | Oil & Gas Operator | Dec 1983 |
| 32 | Bering Operating Company, Inc. | Tyler, TX 75701 | Oil & Gas Operator | May 2001 |
| 33 | Black Diamond Energy, LLC | | Oil & Gas Operator | Oct 2008 |
| 34 | BP Exploration Inc | | Oil & Gas Operator | May 1993 |
| 35 | Brammer Engineering, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 36 | Breakthrough Ventures, LLC | | Oil Operator | Jan 2025 |
| 37 | Brechtel Energy Corporation | | Oil & Gas Operator | Sep 2008 |
| 38 | Bristol Resources Corporation | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2022 |
| 39 | Britlind Oil LLC | | Oil & Gas Operator | Dec 2020 |
| 40 | Browning Oil Company, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 41 | Burlington Res Oil & Gas Co | | Oil & Gas Operator | Dec 2000 |
| 42 | Burlington Res Oil & Gas LP | | Oil & Gas Operator | Mar 2013 |
| 43 | Bushwood Leasing, LLC | | Oil Operator | Dec 2024 |
| 44 | Buttes Resources Company | Houston, TX 77056 | Oil & Gas Operator | May 2007 |
| 45 | C & D Resources, Inc. | | Oil & Gas Operator | Nov 2001 |
| 46 | C. L. Brown, III | | Oil Operator | Dec 1991 |
| 47 | C. L. Brown, Inc. | | Oil Operator | Dec 1999 |
| 48 | C6 Operating, L.L.C. | Keatchie, LA 71046 | Oil & Gas Operator | Oct 2025 |
| 49 | Cajun Minerals, Inc. | | Oil & Gas Operator | Mar 1997 |
| 50 | Cala Oil & Gas | | Oil & Gas Operator | Oct 1997 |
| 51 | Camex Operating Company | | Oil & Gas Operator | Dec 2024 |
| 52 | Camex, Inc. | | Oil & Gas Operator | Jun 1992 |
| 53 | Candice Venture #1 | | Oil & Gas Operator | May 1992 |
| 54 | Cardinal Oil & Gas, Inc. | | Oil & Gas Operator | Jun 1995 |
| 55 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 56 | Carrollton Resources Corp. | | Oil & Gas Operator | Sep 2000 |
| 57 | Caspen Oil, Inc. | Denver, CO 80226 | Oil & Gas Operator | Jul 1993 |
| 58 | Caspen Operating Company | Somerset, TX 78069 | Oil & Gas Operator | Mar 2008 |
| 59 | Castex Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 60 | Castor Production, L.L.C. | | Oil Operator | Dec 2024 |
| 61 | Celeron Oil & Gas Company | | Oil & Gas Operator | Dec 1987 |
| 62 | Cenla Oil Company, LLC | | Oil Operator | Dec 2024 |
| 63 | Central Crude, Inc. | | Oil & Gas Operator | Jul 2014 |
| 64 | Central Resources Inc | Denver, CO 80203 | Oil & Gas Operator | Dec 2019 |
| 65 | Chaparral Energy, Inc. | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2009 |
| 66 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Oct 2025 |
| 67 | Charles F. Word & Associates | | Oil Operator | Dec 1978 |
| 68 | Charleston Oil & Gas, Inc. | | Oil & Gas Operator | Mar 1997 |
| 69 | Chestnut Exploration And Production, Inc. | Richardson, TX 78081 | Oil & Gas Operator | Nov 2020 |
| 70 | Chestnut Petroleum, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Nov 2011 |
| 71 | Chevron Pipe Line Company | Houston, TX 77001 | Oil Operator | Feb 2015 |
| 72 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 73 | Christeve Oil Company, Inc. | Houston, TX 77068 | Oil & Gas Operator | Dec 2022 |
| 74 | Churchill Energy Inc | | Oil & Gas Operator | Sep 2020 |
| 75 | Cibco Resources, LLC | | Oil & Gas Operator | Nov 2024 |
| 76 | Claron Corporation | Houston, TX 77219 | Oil & Gas Operator | Oct 2025 |
| 77 | Clayton W. Williams, Jr. | | Oil & Gas Operator | Sep 1986 |
| 78 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 79 | CNG Producing Co.-Tulsa Div. | | Oil & Gas Operator | Jun 1986 |
| 80 | CNG Producing Company | New Orleans, LA 70112 | Oil & Gas Operator | Dec 2015 |
| 81 | Coast Exploration Co. | | Oil & Gas Operator | Nov 1997 |
| 82 | Coastal Minerals, Inc. | | Oil Operator | Aug 1991 |
| 83 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 84 | Coastal Plains Exploration, LLC | Port Lavaca, TX 77979 | Oil & Gas Operator | Oct 2025 |
| 85 | Coastal Production Inc. | | Oil & Gas Operator | Aug 2000 |
| 86 | Conn Energy Group, LLC | | Oil & Gas Operator | Apr 2024 |
| 87 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 88 | Consolidated Resources Inc | | Oil & Gas Operator | May 2004 |
| 89 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 90 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 91 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 92 | Coteau Energy LLC | | Oil & Gas Operator | Dec 2024 |
| 93 | Cotton Petroleum Corporation | Tulsa, OK 74102 | Oil & Gas Operator | Jan 2005 |
| 94 | Cox Oil & Gas, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2014 |
| 95 | CPBG, LLC | | Oil Operator | Oct 2019 |
| 96 | Crain & Dore Production Co Inc | | Oil & Gas Operator | Oct 1990 |
| 97 | Crawford Energy Operating Co | Houston, TX 77056 | Oil & Gas Operator | Aug 2008 |
| 98 | Crawford Hughes Operating Co. | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 99 | Crimson Explor Operating, Inc. | | Oil & Gas Operator | Dec 2009 |
| 100 | CSV Holdings, Inc. | | Oil & Gas Operator | Dec 2014 |