| 101 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 102 | Crossroads Mineral Prod., L.L.C. | Seguin, TX 78155 | Oil Operator | Apr 2025 |
| 103 | Crossroads Vacuum & Weld. Serv. | Luling, TX 78648 | Oil Operator | Mar 2010 |
| 104 | Cummins & Walker Oil Co., Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2021 |
| 105 | CWS Aceite Operating, Inc. | Cotulla, TX 78014 | Oil & Gas Operator | Aug 2018 |
| 106 | Daniels, C. W. | Stockdale, TX 78160 | Oil & Gas Operator | Dec 2009 |
| 107 | Dbo Oil Incorporated | Georgetown, TX 78628 | Oil & Gas Operator | Apr 2025 |
| 108 | Deagen, Bill & Sons, LTD. | Stockdale, TX 78160 | Oil Operator | May 2018 |
| 109 | Delcar, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Oct 1995 |
| 110 | Delray Oil, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2025 |
| 111 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 112 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Apr 2025 |
| 113 | Dirnett, Inc. | Tuleta, TX 78162 | Oil & Gas Operator | Apr 2025 |
| 114 | DLM Energy | Houston, TX 77058 | Oil & Gas Operator | Sep 1994 |
| 115 | Doege, Donald | La Vernia, TX 78121 | Oil & Gas Operator | Apr 2025 |
| 116 | Dominion Production Company, LLC | Tampa, FL 33606 | Oil & Gas Operator | Apr 2025 |
| 117 | Donoco Oil Company | La Vernia, TX 78121 | Oil & Gas Operator | Apr 2025 |
| 118 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Dec 2014 |
| 119 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Apr 2025 |
| 120 | Double R Oil Co. | Charlotte, TX 78011 | Oil & Gas Operator | May 2010 |
| 121 | Drachen Oil Company | San Antonio, TX 78258 | Oil & Gas Operator | Apr 2025 |
| 122 | Driscoll S.W.D. Inc. | San Antonio, TX 78229 | Oil & Gas Operator | Apr 2025 |
| 123 | DRS Exploration Inc. | San Antonio, TX 78209 | Oil & Gas Operator | May 1999 |
| 124 | Drum Oil & Gas, Inc. | Houston, TX 77082 | Oil & Gas Operator | Apr 2025 |
| 125 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 126 | Dula Production, LLC | Stockdale, TX 78160 | Oil Operator | Apr 2025 |
| 127 | E-P Oil Co. Inc. | Luling, TX 78648 | Oil & Gas Operator | Apr 2025 |
| 128 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Apr 2025 |
| 129 | Earthstone Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2025 |
| 130 | Eex Corporation | Houston, TX 77060 | Oil & Gas Operator | Feb 2000 |
| 131 | Ef Energy, L.L.C. | Houston, TX 77084 | Oil & Gas Operator | Jun 2015 |
| 132 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 133 | Embrey Oil Production Co. | Sutherlnd SPG, TX 78161 | Oil & Gas Operator | Oct 2021 |
| 134 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 135 | Energon3 | Rowlett, TX 75089 | Oil Operator | Apr 2025 |
| 136 | Energy Resource Management, Inc. | Caldwell, TX 77836 | Oil & Gas Operator | Mar 2008 |
| 137 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 138 | Enr Operating, LLC | Eunice, NM 88231 | Oil & Gas Operator | Apr 2025 |
| 139 | Enre Corp. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2005 |
| 140 | Enre LP | Kingwood, TX 77339 | Oil & Gas Operator | Feb 2004 |
| 141 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 142 | Enterprise Crude Oil LLC | Oklahoma City, OK 73102 | Oil Operator | Aug 2011 |
| 143 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 144 | European-Southwest Co. | Houston, TX 77254 | Oil & Gas Operator | Apr 2025 |
| 145 | Everest Resource Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Apr 2025 |
| 146 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 147 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Feb 2025 |
| 148 | Falcon Production Co. | Floresville, TX 78114 | Oil & Gas Operator | Apr 2025 |
| 149 | Falls City Energy Corporation | Poth, TX 78147 | Oil & Gas Operator | May 2000 |
| 150 | Famcor Oil, Inc. | Scottsdale, AZ 85260 | Oil & Gas Operator | Sep 2020 |
| 151 | Federal Energy Development Co. | Dallas, TX 75205 | Oil & Gas Operator | Mar 2011 |
| 152 | Fidelity Petroleum Corporation | Plano, TX 75074 | Oil & Gas Operator | Apr 2025 |
| 153 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 154 | Finger Oil & Gas, Inc. | Castroville, TX 78009 | Oil & Gas Operator | May 2021 |
| 155 | First Rock, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2025 |
| 156 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 157 | Fort Worth Natural Gas, Inc. | Dallas, TX 75254 | Oil & Gas Operator | Apr 2025 |
| 158 | Freeport-McMoran Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 159 | G & K Operating, LLC | Poth, TX 78147 | Oil & Gas Operator | Apr 2025 |
| 160 | Gasper Rice Resources, LTD. | Houston, TX 77068 | Oil & Gas Operator | Apr 2025 |
| 161 | Gauge Oil Company | Luling, TX 78648 | Oil & Gas Operator | Apr 2025 |
| 162 | Gauntt, Inc. | San Marcos, TX 78666 | Oil & Gas Operator | Dec 2024 |
| 163 | Geo-Graphic Production, Inc. | Gonzales, TX 78629 | Oil & Gas Operator | Apr 2025 |
| 164 | Geodominion Petroleum | Corpus Chrsti, TX 78403 | Oil & Gas Operator | May 2012 |
| 165 | Geomeg Energy Operating Co., LLC | Aransas Pass, TX 78336 | Oil & Gas Operator | Apr 2025 |
| 166 | Geomeg Operating, LLC | Dripping SPGS, TX 78620 | Oil Operator | Nov 2010 |
| 167 | Ginco Operating Co. | San Antonio, TX 78217 | Oil & Gas Operator | Apr 2025 |
| 168 | Glenco Oil & Gas Company | Seguin, TX 78155 | Oil & Gas Operator | Dec 1994 |
| 169 | Global XRC Corp | Pittsburg, TX 75686 | Oil & Gas Operator | Apr 2025 |
| 170 | Good Ol'Boys Oil Company | Houston, TX 77057 | Oil & Gas Operator | Apr 2025 |
| 171 | Grammer, John, Oil Account | La Vernia, TX 78121 | Oil & Gas Operator | Aug 2017 |
| 172 | GRB Properties, Inc. | Midland, TX 79705 | Oil & Gas Operator | Mar 2003 |
| 173 | Great West Energy & Expl., Inc. | Addison, TX 75001 | Oil & Gas Operator | Mar 2008 |
| 174 | Greenwerks Outdoor Services LLC | Stockdale, TX 78160 | Oil Operator | Apr 2025 |
| 175 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 176 | Gulfmark Energy Inc | Houston, TX 77027 | Gas Operator | Apr 2023 |
| 177 | Gulfstar Properties, Inc. | San Antonio, TX 78229 | Oil & Gas Operator | Apr 2025 |
| 178 | Gulftex Energy II, LP | San Antonio, TX 78258 | Oil & Gas Operator | Jan 2013 |
| 179 | Gulftex Energy, LLC | San Antonio, TX 78257 | Oil & Gas Operator | Apr 2025 |
| 180 | H & P Partnership | La Vernia, TX 78121 | Oil Operator | Apr 2025 |
| 181 | H&K Energy | Stockdale, TX 78160 | Oil & Gas Operator | Jul 2005 |
| 182 | H. & J. Drilling Company | Fort Worth, TX 76114 | Oil & Gas Operator | Aug 2003 |
| 183 | H.K.E. | Stafford, TX 77497 | Oil & Gas Operator | Apr 2025 |
| 184 | Hankamer, Curtis Corporation,The | Houston, TX 77024 | Oil & Gas Operator | Apr 2025 |
| 185 | Hawn Brothers | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2003 |
| 186 | Henry Petroleum Corp. | Midland, TX 79703 | Oil & Gas Operator | Mar 2001 |
| 187 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 188 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 189 | Hibbard Energy, LP | Whitehouse, TX 75791 | Oil & Gas Operator | Apr 2025 |
| 190 | Holloway Oil Company | Austin, TX 78764 | Oil & Gas Operator | Feb 2004 |
| 191 | Hollub, Lambert Drilling Company | Seguin, TX 78155 | Oil & Gas Operator | Apr 2025 |
| 192 | Hominy Consulting, LLC | Canadian, TX 79014 | Oil & Gas Operator | Apr 2025 |
| 193 | Horizon Ridge Oil Company | Austin, TX 78738 | Oil Operator | Apr 2025 |
| 194 | Houston Gulf Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 2025 |
| 195 | Houston Hydrocarbons, Inc. (A) | Houston, TX 77042 | Oil & Gas Operator | Sep 2004 |
| 196 | Hughes, Dan A. Company | Beeville, TX 78104 | Oil & Gas Operator | May 2006 |
| 197 | Hughes, Dan A. Company, L.P. | Beeville, TX 78104 | Oil & Gas Operator | Apr 2025 |
| 198 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Apr 2025 |
| 199 | Huntwood Resources, LLC | Huntsville, TX 77340 | Oil Operator | Apr 2025 |
| 200 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |