| 1 | 3tec Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 2 | 84 Energy LLC | Sugar Land, TX 77487 | Oil & Gas Operator | Jul 2025 |
| 3 | A.O.E. Operators, Inc. | Fulshear, TX 77441 | Oil & Gas Operator | Jul 2025 |
| 4 | Accidie Exploration And Dev.,Inc | Plano, TX 75023 | Oil & Gas Operator | Jul 2025 |
| 5 | Alcorn Prod Co. | Victoria, TX 77902 | Oil & Gas Operator | Mar 1997 |
| 6 | Allar Co., The | Graham, TX 76450 | Oil & Gas Operator | Dec 2004 |
| 7 | Alpine Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 8 | Altair Energy Corp. | Tyler, TX 75702 | Oil & Gas Operator | Jun 1994 |
| 9 | Amax Oil & Gas Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Nov 2014 |
| 10 | Amerada Hess Corporation | Houston, TX 77252 | Oil & Gas Operator | Aug 2013 |
| 11 | American Cascade Energy, Inc. | Barker, TX 77413 | Oil & Gas Operator | Jul 2025 |
| 12 | American Exploration Company | Houston, TX 77010 | Oil & Gas Operator | Jan 2000 |
| 13 | Amoco Production Co. | Houston, TX 77253 | Oil & Gas Operator | Jun 2015 |
| 14 | Anadarko E&P Company LP | Houston, TX 77251 | Oil & Gas Operator | Aug 2014 |
| 15 | Anadarko E&P Onshore LLC | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 16 | Anadarko Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | May 2025 |
| 17 | Antara Resources Inc | Houston, TX 77002 | Oil & Gas Operator | Apr 2004 |
| 18 | Apache Corporation | Houston, TX 77042 | Oil & Gas Operator | Jul 2025 |
| 19 | Aquinas Oil & Gas, LLC | Muenster, TX 76252 | Oil Operator | Jul 2025 |
| 20 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 21 | Arco Oil & Gas Company | Plano, TX 75086 | Oil & Gas Operator | Mar 2006 |
| 22 | Arrowhead Operating Inc. | Argyle, TX 76226 | Oil & Gas Operator | Jul 2025 |
| 23 | Atasca Resources Inc | Houston, TX 77219 | Oil & Gas Operator | Jul 2025 |
| 24 | Atropos Exploration Company | Dallas, TX 75225 | Oil & Gas Operator | Jul 2025 |
| 25 | Austin Resources Corporation | Houston, TX 77027 | Oil & Gas Operator | Mar 2008 |
| 26 | Balance Production Corporation | Temple, TX 76503 | Oil & Gas Operator | Jul 2025 |
| 27 | Barbee, R.L. Operating, Inc. | Corpus Chrsti, TX 78427 | Oil & Gas Operator | Jul 2025 |
| 28 | Barrow-Shaver Resources Co. | Tyler, TX 75703 | Oil & Gas Operator | Jul 2025 |
| 29 | Basa Resources, Inc. | Dallas, TX 75254 | Oil & Gas Operator | Jul 2025 |
| 30 | Baxter, Murphy H. | Houston, TX 77002 | Oil & Gas Operator | Sep 1998 |
| 31 | Beard Oil Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Aug 2013 |
| 32 | Beehive Operating, LLC | Graham, TX 76450 | Oil & Gas Operator | Jul 2025 |
| 33 | Bellwether Exploration Company | Houston, TX 77010 | Oil & Gas Operator | May 2001 |
| 34 | Bend Petroleum Corp. | Muenster, TX 76252 | Oil & Gas Operator | Nov 2023 |
| 35 | Big Creek Operating Company LLC | Houston, TX 77065 | Oil & Gas Operator | Jul 2025 |
| 36 | Bison Energy Partners, LTD. | Houston, TX 77060 | Oil & Gas Operator | Apr 2002 |
| 37 | Block "T" Petroleum, Inc. | Tyler, TX 75707 | Oil & Gas Operator | Jul 2025 |
| 38 | Block T Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Dec 2024 |
| 39 | BLS Resources, Inc. | Rosharon, TX 77583 | Oil & Gas Operator | Feb 2001 |
| 40 | Blue Grass Energy, Inc. | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 41 | Bomar Oil & Gas, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Dec 2020 |
| 42 | Booher Engineering, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Jul 2025 |
| 43 | Bosco Petroleum LLC | Muenster, TX 76252 | Oil Operator | Jul 2025 |
| 44 | Bowman, Fred Inc. | Dallas, TX 75225 | Oil & Gas Operator | Feb 2014 |
| 45 | Bozeman, John F. | Rosenberg, TX 77471 | Oil & Gas Operator | Sep 2005 |
| 46 | Brazos Resources, Inc. | College Sta, TX 77840 | Oil & Gas Operator | Dec 1998 |
| 47 | BRG Lone Star LTD. | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2025 |
| 48 | BRG Petroleum, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2020 |
| 49 | Bright Horizon Texas LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2016 |
| 50 | Brooks Petroleum Company | Tyler, TX 75703 | Oil & Gas Operator | Jul 2025 |
| 51 | Bryant & Carr, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 1994 |
| 52 | Bryant - Chase Energy Corp. | Tyler, TX 75701 | Oil & Gas Operator | Aug 2004 |
| 53 | Buffco Production, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jul 2025 |
| 54 | Burk Royalty Co., LTD. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2025 |
| 55 | Buttram Energies Inc | Oklahoma City, OK 73112-7235 | Oil & Gas Operator | Nov 2021 |
| 56 | C. W. Resources, Inc. | Longview, TX 75604 | Oil & Gas Operator | Jul 2025 |
| 57 | Cabot Oil & Gas Corporation | Houston, TX 77024 | Oil & Gas Operator | Apr 2025 |
| 58 | Calpine Natural Gas Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2002 |
| 59 | Calpine Natural Gas Company L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 60 | Calpine Natural Gas L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2006 |
| 61 | Cameron Engineering, Inc | Montgomery, TX 77356 | Oil & Gas Operator | Jun 2003 |
| 62 | Card Operating Company, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Dec 1995 |
| 63 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 64 | Castle Exploration Company Inc | Blue Bell, PA 19422 | Oil & Gas Operator | May 2018 |
| 65 | CH-Seon Inc. | Dallas, TX 75251 | Oil & Gas Operator | Jul 2025 |
| 66 | Chalker Energy Management II,LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2008 |
| 67 | Chesapeake Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Jul 2025 |
| 68 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2025 |
| 69 | Chevron Midcontinent, L.P. | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 70 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 71 | Christico Petroleum Company | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2025 |
| 72 | Classic Oil & Gas, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jan 2004 |
| 73 | Cochise Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 74 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 75 | Contrast Energy, LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jul 2025 |
| 76 | Cook Exploration Co. | Longview, TX 75602 | Oil & Gas Operator | Jul 2025 |
| 77 | Cordillera Energy PRTNRS III,LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2012 |
| 78 | Cory, Kenneth W. LTD. | Bellaire, TX 77401 | Oil & Gas Operator | Jul 2025 |
| 79 | Crescent Pass Energy, LLC | Houston, TX 77070 | Oil & Gas Operator | Jul 2025 |
| 80 | Crimson Exploration Inc. | Houston, TX 77060 | Oil & Gas Operator | Apr 2006 |
| 81 | Crimson Exploration Oper., Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 82 | Crow, David | Shreveport, LA 71106 | Oil & Gas Operator | May 2001 |
| 83 | Culver & Cain Production LLC | Tyler, TX 75711 | Oil & Gas Operator | Jul 2025 |
| 84 | Curzac Oil And Gas, LLC | Plano, TX 75075 | Oil & Gas Operator | Jul 2025 |
| 85 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 86 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Apr 2025 |
| 87 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 88 | Denman-Friesen Co. | Lufkin, TX 75901 | Oil & Gas Operator | Nov 2006 |
| 89 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 90 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2025 |
| 91 | Dixon Exploration Inc | Abilene, TX 79604 | Oil & Gas Operator | Oct 2019 |
| 92 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 93 | Edge Petroleum Oper. Co., Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 94 | Elliott Oil & Gas Operating Co. | Magnolia, TX 77354 | Oil & Gas Operator | Jul 2025 |
| 95 | Empire Texas Operating LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Jul 2025 |
| 96 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 97 | Energy & Expl. PRTNRS Oper., LP | Fort Worth, TX 76147 | Oil & Gas Operator | Oct 2016 |
| 98 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 99 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | Mar 2025 |
| 100 | Enfield Operating Company, LLC | Coppell, TX 75019 | Oil Operator | Jul 2025 |