| 101 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Dec 2014 |
| 102 | Double J Operating Company, Inc. | San Antonio, TX 78205 | Oil Operator | Jan 2008 |
| 103 | Duplantis Energy, LLC | Pleasanton, TX 78064 | Oil Operator | Mar 2025 |
| 104 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Mar 2025 |
| 105 | E-Cor, Inc. | Austin, TX 78734 | Gas Operator | Feb 1999 |
| 106 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Mar 2025 |
| 107 | Edisto Resources Corp | Houston, TX 77057 | Oil & Gas Operator | Oct 1999 |
| 108 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 109 | El Indio Energy LLC | Austin, TX 78746 | Oil Operator | Mar 2025 |
| 110 | El Toro Resources LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Mar 2025 |
| 111 | Ellsworth, H. P. O&G Properties | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Mar 2025 |
| 112 | Enre Corp. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2005 |
| 113 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 114 | Espada Operating LLC | San Antonio, TX 78209 | Oil Operator | Mar 2025 |
| 115 | Etoco, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 116 | European-Southwest Co. | Houston, TX 77254 | Oil & Gas Operator | Mar 2025 |
| 117 | Exco Operating Company, LP | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 118 | Exotic Oil & Gas LLC | Indiana, PA 15701-3634 | Oil & Gas Operator | Dec 2024 |
| 119 | Exploration Company, The | San Antonio, TX 78258 | Oil & Gas Operator | Jun 2010 |
| 120 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 121 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 122 | F & M Oil & Gas Co | Midland, TX 79702 | Oil & Gas Operator | Feb 2000 |
| 123 | Famcor Oil, Inc. | Scottsdale, AZ 85260 | Oil & Gas Operator | Sep 2020 |
| 124 | Field Petroleum Corp. | San Antonio, TX 78216 | Oil & Gas Operator | Mar 2025 |
| 125 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Mar 2025 |
| 126 | First Rock, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2025 |
| 127 | Flint Oak Energy, LLC | Montgomery, TX 77356 | Oil & Gas Operator | Mar 2025 |
| 128 | Forbes, C. C. Company | Alice, TX 78333 | Oil & Gas Operator | Sep 2015 |
| 129 | Formentera Operations LLC | Austin, TX 78701 | Oil & Gas Operator | Mar 2025 |
| 130 | Fortune Operating Company | Willis, TX 77378 | Oil & Gas Operator | Mar 2025 |
| 131 | FX Energy Operating, LLC | Canadian, TX 79014 | Oil & Gas Operator | Mar 2025 |
| 132 | Genesis Gas & Oil LLC | Kansas City, MO 64108 | Oil & Gas Operator | Aug 2011 |
| 133 | Genesis Producing Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2007 |
| 134 | Genesis St Operating LLC | Kansas City, MO 64108 | Oil & Gas Operator | Mar 2025 |
| 135 | Glenco Oil & Gas Company | Seguin, TX 78155 | Oil & Gas Operator | Dec 1994 |
| 136 | GLG Energy LP | Austin, TX 78701 | Oil & Gas Operator | Jun 1994 |
| 137 | Golden Child, Inc. | San Antonio, TX 78213 | Oil & Gas Operator | Mar 2025 |
| 138 | Gould Energy Co. | Owasso, OK 74055 | Oil & Gas Operator | Mar 2005 |
| 139 | Great Western Drilling Co | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 140 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 141 | Gulf Production Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Apr 2015 |
| 142 | Gulfmark Energy Inc | Houston, TX 77027 | Gas Operator | Apr 2023 |
| 143 | H. & J. Drilling Company | Fort Worth, TX 76114 | Oil & Gas Operator | Aug 2003 |
| 144 | Hamilton, Clay | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Mar 2025 |
| 145 | Harvard Petroleum Corporation | Roswell, NM 88201 | Oil & Gas Operator | Dec 2004 |
| 146 | Harvey Brothers Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Jul 2004 |
| 147 | Hawthorn Energy Partners, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2025 |
| 148 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 149 | Heart Land Petroleum Corporation | Abilene, TX 79604 | Oil & Gas Operator | Mar 2008 |
| 150 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 151 | Hexagon Oil And Gas Inc. | Fort Worth, TX 76132 | Oil & Gas Operator | Mar 2025 |
| 152 | Holifield Oil Company | Giddings, TX 78942 | Oil & Gas Operator | Mar 2009 |
| 153 | Hollimon Oil Corporation | Castroville, TX 78009 | Oil & Gas Operator | Nov 2016 |
| 154 | Hughes, Dan A. Company | Beeville, TX 78104 | Oil & Gas Operator | May 2006 |
| 155 | Hughes, Dan A. Company, L.P. | Beeville, TX 78104 | Oil & Gas Operator | Mar 2025 |
| 156 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2025 |
| 157 | Ineos USA Oil & Gas LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2025 |
| 158 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 159 | Inland Ocean, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Mar 2025 |
| 160 | Intercity Management Corp. | Corpus Chrsti, TX 78412 | Oil & Gas Operator | Mar 2025 |
| 161 | Ipact | Austin, TX 78734 | Oil & Gas Operator | Mar 2025 |
| 162 | Iwt Energy Partners LLC | Austin, TX 78731 | Oil Operator | Mar 2025 |
| 163 | J-W Operating Company | Christoval, TX 76935 | Oil & Gas Operator | Mar 2025 |
| 164 | Jab Operating, Inc. | San Antonio, TX 78205 | Oil & Gas Operator | Dec 2008 |
| 165 | JB Oil & Gas Well Service | Dilley, TX 78017 | Oil & Gas Operator | Mar 2025 |
| 166 | Jenco Petroleum Corporation | The Woodlands, TX 77380 | Oil Operator | Mar 2025 |
| 167 | Jenex Petroleum Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Mar 2025 |
| 168 | Jennings Exploration Company | Beeville, TX 78102 | Oil & Gas Operator | Feb 2024 |
| 169 | JL Resources, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Mar 2025 |
| 170 | Joint Resources Company | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2025 |
| 171 | Kachina Oil & Gas Inc. | Austin, TX 78766 | Oil & Gas Operator | Jul 2002 |
| 172 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jan 2025 |
| 173 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 174 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Dec 2024 |
| 175 | Killam Oil Co., LTD. | Laredo, TX 78042 | Oil & Gas Operator | Mar 2025 |
| 176 | Killam Oil Company | Laredo, TX 78042 | Oil & Gas Operator | Mar 1994 |
| 177 | Kincaid/Hadden | Uvalde, TX 78802 | Oil & Gas Operator | Feb 1997 |
| 178 | Kinlaw Oil Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 179 | Koven Production Co. | San Antonio, TX 78232 | Oil & Gas Operator | Aug 2003 |
| 180 | KP Exploration, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1997 |
| 181 | L & J Exploration, LLC | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Mar 2025 |
| 182 | La Jolla Oil & Gas, Inc. | Frisco, TX 75034 | Oil & Gas Operator | Mar 2025 |
| 183 | Larron Energy Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2015 |
| 184 | Laurel Fuel Company | Jackson, MS 39206 | Oil & Gas Operator | Dec 1996 |
| 185 | Lavanco Energy, Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2006 |
| 186 | Lavanco Energy, LTD. | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2024 |
| 187 | Live Oak Gas Company | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 188 | Lively Energy & Development Corp | Boerne, TX 78015 | Oil & Gas Operator | May 2015 |
| 189 | LMP Petroleum, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Jan 2010 |
| 190 | Longhorn Oil Properties, Inc. | Pottsboro, TX 75076 | Oil & Gas Operator | Mar 2025 |
| 191 | Lovelady, I. W. | Albuquerque, NM 87111 | Oil & Gas Operator | Jan 1996 |
| 192 | Lucas Energy, Inc. | Houston, TX 77067 | Oil & Gas Operator | Feb 2017 |
| 193 | Lynch, W. W. | San Antonio, TX 78205 | Oil & Gas Operator | Jul 2006 |
| 194 | Lynch, W. Waldo | Uvalde, TX 78801 | Oil & Gas Operator | Jan 1996 |
| 195 | Lynch, Wilbur Waldo, Estate Of | New Braunfels, TX 78130 | Oil & Gas Operator | Oct 2017 |
| 196 | Magnolia Oil & Gas Operating LLC | Houston, TX 77046 | Oil & Gas Operator | Mar 2025 |
| 197 | Magnum Engineering Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Mar 2025 |
| 198 | Magnum Producing & Operating Co. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jan 2004 |
| 199 | Majestic Petroleum Corporation | Dallas, TX 75230 | Oil & Gas Operator | Oct 1996 |
| 200 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |