| 101 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 102 | Petro-Hunt Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2003 |
| 103 | Petro-Hunt, L.L.C. | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 104 | Petroleum Management, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Feb 2026 |
| 105 | Petrovybe Opco LLC | Plano, TX 75093 | Oil & Gas Operator | Feb 2026 |
| 106 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Jan 2025 |
| 107 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Feb 2026 |
| 108 | Plains Exploration & Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Jul 2013 |
| 109 | Poff, H. Bryan | Fort Worth, TX 76103 | Oil & Gas Operator | Mar 2008 |
| 110 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 111 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 112 | Quintana Pet. Corp. | Refugio, TX 78377 | Oil & Gas Operator | Dec 2000 |
| 113 | Reef Exploration, Inc. (A-1) | Richardson, TX 75080 | Oil & Gas Operator | Oct 2006 |
| 114 | Reveille Resources | Houston, TX 77084 | Oil & Gas Operator | Apr 2011 |
| 115 | Reveille Resources (Texas), Inc. | Houston, TX 77084 | Oil & Gas Operator | Jan 2013 |
| 116 | Rincon Petroleum Corporation | Corpus Chrsti, TX 78427 | Oil & Gas Operator | Feb 2026 |
| 117 | Rio-Tex, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Feb 2026 |
| 118 | Risco La Sara Operations, LLC | Houston, TX 77056 | Oil & Gas Operator | Aug 2014 |
| 119 | Safari Production Company, Inc. | McAllen, TX 78501 | Oil & Gas Operator | Feb 2026 |
| 120 | Saga Petroleum Corp. | Midland, TX 79701 | Oil & Gas Operator | Mar 2008 |
| 121 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 122 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 123 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2026 |
| 124 | Sanchez Oil & Gas Corporation | Houston, TX 77056 | Oil & Gas Operator | Feb 2026 |
| 125 | Sanchez-O'Brien Oil & Gas Corp | Houston, TX 77057 | Oil & Gas Operator | May 1998 |
| 126 | Santos USA Corp. | Houston, TX 77042 | Oil & Gas Operator | Dec 2008 |
| 127 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 128 | Shoco Production LLC | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2026 |
| 129 | Shoco Production, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | May 2020 |
| 130 | Slimhole Engineering Co., Inc. | Richmond, TX 77469 | Oil & Gas Operator | Feb 2026 |
| 131 | Smith Production Inc. | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2026 |
| 132 | South Leeville, LLC | Houston, TX 77069 | Oil & Gas Operator | Oct 2022 |
| 133 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Feb 2026 |
| 134 | Sue-Ann Operating, L.C. | Victoria, TX 77903 | Oil & Gas Operator | Feb 2026 |
| 135 | Suemaur Expl. & Prod., LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jun 2024 |
| 136 | Suemaur Exploration, Inc. | Corpus Chrsti, TX 78470 | Oil & Gas Operator | Mar 2008 |
| 137 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 138 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |
| 139 | Synergy Oil & Gas, Inc. (A) | Houston, TX 77024 | Oil & Gas Operator | Aug 2001 |
| 140 | Synergy Oil & Gas, L.P. | Houston, TX 77024 | Oil & Gas Operator | May 2012 |
| 141 | Tasca Exploration Company | Houston, TX 77257 | Oil & Gas Operator | Jun 2002 |
| 142 | Taubert & Steed | Wichita Falls, TX 76301 | Oil & Gas Operator | Aug 2001 |
| 143 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Feb 2026 |
| 144 | Texas Oil And Gas Operating, LLC | Friendswood, TX 77546 | Oil & Gas Operator | Feb 2026 |
| 145 | Thorp Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2014 |
| 146 | Tucker Operating Co., Inc. | Victoria, TX 77903 | Oil & Gas Operator | Feb 2026 |
| 147 | U.S. Enercorp, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2004 |
| 148 | U.S. Enercorp, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2019 |
| 149 | Ultra Oil & Gas, Inc. | Centerton, AR 72719 | Oil & Gas Operator | Feb 2026 |
| 150 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Feb 2026 |
| 151 | Vantage Operating, LLC | San Antonio, TX 78230 | Oil & Gas Operator | Feb 2026 |
| 152 | Wadi Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Feb 2026 |
| 153 | Wagner Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2026 |
| 154 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 155 | White Oak Operating Company LLC | Houston, TX 77077 | Oil & Gas Operator | Feb 2026 |
| 156 | Whittington Operating Company | Houston, TX 77069 | Oil & Gas Operator | Feb 2026 |
| 157 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 158 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Feb 2026 |
| 159 | Yturria, Frank D. | Brownsville, TX 78520 | Oil & Gas Operator | Mar 2008 |
| 160 | Zinke & Trumbo, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2007 |