| 1 | 1776 Energy Operators, LLC | Houston, TX 77070 | Oil & Gas Operator | Apr 2021 |
| 2 | 3-T Exploration, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2021 |
| 3 | 3tec Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2020 |
| 4 | 4H Oil Co. | | Oil Operator | Dec 1992 |
| 5 | A & B Oil Company | | Oil & Gas Operator | Apr 2015 |
| 6 | A & C Gas Productions, Inc. | | Gas Operator | Mar 2012 |
| 7 | A & F Oil Company | | Oil & Gas Operator | Sep 2018 |
| 8 | A & F Production Company | | Oil Operator | Sep 2018 |
| 9 | A A Company | | Gas Operator | Jun 2005 |
| 10 | A J & A, Inc. | | Gas Operator | Feb 2009 |
| 11 | A J Ferguson | | Oil Operator | Apr 1988 |
| 12 | A&K Production LLC Of Texas | | Oil & Gas Operator | Aug 2018 |
| 13 | A. J. Hodges, Ind. Inc Et Al | | Oil & Gas Operator | Jan 1979 |
| 14 | A. L. Coon | | Oil Operator | May 1979 |
| 15 | A. M. A. Chiles | | Oil & Gas Operator | Sep 2018 |
| 16 | A. Michael Hyde Oil & Gas Co. | | Oil & Gas Operator | Oct 1987 |
| 17 | A. R. Wherrett Trustees | | Oil Operator | Jan 1987 |
| 18 | A. T. Teague, Jr. | | Oil Operator | Aug 1993 |
| 19 | A. W. Sour, Jr. | | Oil Operator | Apr 2003 |
| 20 | A.J. Hodges Industries, Inc. | | Oil & Gas Operator | Sep 1987 |
| 21 | Abco Petroleum Corp. | | Oil & Gas Operator | Feb 1999 |
| 22 | Aberdeen American Petroleum Co., Inc. | | Oil & Gas Operator | Nov 1989 |
| 23 | Aberdeen Petroleum (USA) Inc. | Abilene, TX 79608 | Oil & Gas Operator | Jul 1994 |
| 24 | Abney Oil Company, Inc. | | Oil Operator | Mar 1981 |
| 25 | Abraxas Petroleum Corporation | San Antonio, TX 78258 | Oil & Gas Operator | Apr 2021 |
| 26 | Acadian Land & Expl., Inc. | | Oil & Gas Operator | May 1992 |
| 27 | Acadiana Gas Systems, Inc. | | Oil & Gas Operator | Jan 1999 |
| 28 | Acadiana Reserves, Inc. | | Oil & Gas Operator | Oct 1984 |
| 29 | Acadienergy, Inc. | | Oil & Gas Operator | Jun 1988 |
| 30 | Ace Drilling Services, Inc. | | Oil & Gas Operator | Sep 1987 |
| 31 | Ace Production | | Oil Operator | Jul 1993 |
| 32 | Achilles Oil, LLC | | Oil & Gas Operator | Jan 2021 |
| 33 | Activa Resources, LLC | San Antonio, TX 78205 | Oil & Gas Operator | Apr 2021 |
| 34 | Ada Oil Exploration Corp | | Oil & Gas Operator | Feb 1986 |
| 35 | Adam Petroleum Services, Inc. | | Oil Operator | Jul 1999 |
| 36 | Adams Resources Expl. Corp. | Houston, TX 77001 | Oil & Gas Operator | Jan 2018 |
| 37 | Adco Producing Co. | | Oil & Gas Operator | Mar 1989 |
| 38 | Addie, James & John Thornton | | Oil & Gas Operator | Oct 2018 |
| 39 | Addison Oil, LLC | Addison, TX 75001 | Oil & Gas Operator | Mar 2013 |
| 40 | Addison Resources Inc. | | Oil & Gas Operator | Jul 1998 |
| 41 | Adobe Energy Company | | Oil & Gas Operator | Sep 2010 |
| 42 | Adobe Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Dec 2000 |
| 43 | Aegis Energy, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Sep 1998 |
| 44 | Aethon Energy Operating LLC | Dallas, TX 75251 | Oil & Gas Operator | Apr 2021 |
| 45 | Affiliated Holdings, Inc. | | Oil & Gas Operator | Sep 2014 |
| 46 | Agate Petroleum, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Aug 2015 |
| 47 | Agip Petroleum Co., Inc. | | Oil & Gas Operator | Jan 2003 |
| 48 | Aimhigh America, Inc. | | Oil & Gas Operator | Jun 2016 |
| 49 | Ainsworth Prod Co. | | Oil Operator | Oct 1985 |
| 50 | Ainsworth Rig Service, LLC | | Oil Operator | Aug 2018 |
| 51 | Aix Energy Inc | | Oil & Gas Operator | Jul 2016 |
| 52 | Akin Beene Resources LLC | | Oil & Gas Operator | Sep 2018 |
| 53 | Al & D.L. Chiles | | Oil & Gas Operator | Jul 1991 |
| 54 | Al Chiles II | | Oil Operator | Aug 2018 |
| 55 | Aladdin Energy, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Jul 1998 |
| 56 | Alagood & Alagood | | Oil & Gas Operator | May 1981 |
| 57 | Alameda Oil Company | | Oil Operator | Aug 1999 |
| 58 | Alamo Petroleum Company | | Oil & Gas Operator | Jun 1985 |
| 59 | Alcorn Prod Co. | Victoria, TX 77902 | Oil & Gas Operator | Mar 1997 |
| 60 | Alegre Energy, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Apr 2021 |
| 61 | Alexander Brothers Oil | | Oil Operator | Jan 1999 |
| 62 | Alexandria Oil, Inc. | | Oil Operator | Dec 1991 |
| 63 | Alfred C. Glassell, Jr. | | Oil & Gas Operator | Apr 2007 |
| 64 | Alfred Lamson-James A. Crocker | | Oil & Gas Operator | Sep 1986 |
| 65 | Alinet Corporation | | Oil & Gas Operator | Oct 2017 |
| 66 | Allen Brothers | | Oil & Gas Operator | Aug 2018 |
| 67 | Allen Petroleum Company | | Oil Operator | Apr 1996 |
| 68 | Allen Petroleum, Inc. | | Oil Operator | Jul 2010 |
| 69 | Alliance Exploration Corp. | | Oil & Gas Operator | Mar 1983 |
| 70 | Alliance Oil & Gas Co Inc | Corinth, TX 76205 | Oil & Gas Operator | Mar 2015 |
| 71 | Alliance Operating Corporation | | Oil & Gas Operator | Jan 1995 |
| 72 | Alliance Resources (USA), Inc. | | Oil & Gas Operator | Oct 2002 |
| 73 | Alliance Resources Corporation | Dallas, TX 75367 | Oil & Gas Operator | Apr 2021 |
| 74 | Allied Exploration, Inc. | | Oil & Gas Operator | Oct 2018 |
| 75 | Allied Petroleum Company | | Gas Operator | Jan 1992 |
| 76 | Allied-Gulf Energy, LLC | Lafayette, LA 70508 | Oil & Gas Operator | Apr 2021 |
| 77 | Allison/Hobbs Inc. | Alba, TX 75410 | Oil & Gas Operator | Apr 2021 |
| 78 | Alltex Exploration, Inc. | Houston, TX 77056 | Oil & Gas Operator | Apr 2021 |
| 79 | Alpha Oil & Gas Inc. | | Oil & Gas Operator | Sep 1989 |
| 80 | Alpha Petroleum | | Oil & Gas Operator | Sep 2018 |
| 81 | Alpha Resources, Inc | | Oil & Gas Operator | Jun 2003 |
| 82 | Alpine Energy Corp. | | Oil & Gas Operator | Jun 2004 |
| 83 | Alpine Energy, Inc. | | Oil & Gas Operator | Dec 1999 |
| 84 | Alpine Expl. Companies, Inc. | | Oil & Gas Operator | Sep 2018 |
| 85 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 86 | Alpine Well Service, Inc. | | Oil & Gas Operator | Feb 2021 |
| 87 | Alta Mesa Services, LP | Houston, TX 77084 | Oil & Gas Operator | Apr 2021 |
| 88 | Altair Corporation | | Oil & Gas Operator | Mar 2003 |
| 89 | Altair Energy Corp. | Tyler, TX 75702 | Oil & Gas Operator | Jun 1994 |
| 90 | Alva J. Dixon | | Oil & Gas Operator | Aug 1991 |
| 91 | Alvin & Roger Wilson | | Oil Operator | Dec 2007 |
| 92 | Alvin Wilson, Et Al | | Oil Operator | May 1991 |
| 93 | Am Oil Company | Cyril, OK 73029-0053 | Oil & Gas Operator | Jan 2021 |
| 94 | Amalgamated Bonanza Petr. LTD. | | Oil & Gas Operator | Apr 1980 |
| 95 | Amarex Inc | | Oil & Gas Operator | Dec 1996 |
| 96 | Amarillo Oil Company | | Oil & Gas Operator | Aug 1980 |
| 97 | Amax Oil & Gas Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2009 |
| 98 | Amax Petroleum Corporation | Houston, TX 77042 | Oil & Gas Operator | Dec 2015 |
| 99 | Ambrit Energy Corp. | Garland, TX 75044 | Oil & Gas Operator | May 1999 |
| 100 | Amer. Intl. Petroleum Corp. | | Oil & Gas Operator | Dec 1990 |