| 101 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 102 | Dorchester Operating Company LLC | Refugio, TX 78377 | Oil & Gas Operator | May 2025 |
| 103 | Double Play Oil & Gas | Portland, TX 78374 | Oil & Gas Operator | Dec 2001 |
| 104 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 105 | Drillmar Operating Company | Houston, TX 77019 | Oil & Gas Operator | Jun 2013 |
| 106 | Driscoll S.W.D. Inc. | San Antonio, TX 78229 | Oil & Gas Operator | May 2025 |
| 107 | Durst Oil Company | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Sep 2000 |
| 108 | Dynamic Petroleum Res., Inc. | Houston, TX 77068 | Oil & Gas Operator | Jul 1994 |
| 109 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | May 2025 |
| 110 | Eclipse Services, Inc. * | La Grange, TX 78945 | Oil & Gas Operator | Jul 2003 |
| 111 | Edco Energy, Inc. | Austin, TX 78738 | Oil & Gas Operator | May 2003 |
| 112 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Mar 2025 |
| 113 | Emerald Oil & Gas LC | Fort Worth, TX 76109 | Oil & Gas Operator | May 2025 |
| 114 | Endeavor Production Company | San Angelo, TX 76904 | Oil & Gas Operator | Mar 2008 |
| 115 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 116 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 117 | Esperanza Energy Corp. | Prosper, TX 75078 | Oil & Gas Operator | Mar 2015 |
| 118 | Everest Resource Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | May 2025 |
| 119 | Exotic Oil & Gas LLC | Indiana, PA 15701-3634 | Oil & Gas Operator | Dec 2024 |
| 120 | Express Oil And Gas | La Grange, TX 78945 | Oil & Gas Operator | May 2025 |
| 121 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 122 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | May 2025 |
| 123 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 124 | Finaly Resources LLC | Sunset Beach, CA 90742 | Oil & Gas Operator | May 2025 |
| 125 | Fischer Operating Corporation | Victoria, TX 77902 | Oil & Gas Operator | Jan 1999 |
| 126 | Five-Jab, Inc. | Tomball, TX 77377 | Oil & Gas Operator | May 2025 |
| 127 | Flournoy Production Co. | Alice, TX 78333 | Oil & Gas Operator | Dec 2002 |
| 128 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 129 | Freeman, James C. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Sep 2000 |
| 130 | Frostwood Energy, LLC | Houston, TX 77219 | Oil & Gas Operator | May 2025 |
| 131 | Gaea Services, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Sep 2021 |
| 132 | Gaither Petroleum Corporation | Katy, TX 77493 | Oil & Gas Operator | May 2025 |
| 133 | Galilee Oil Investments LLC | San Antonio, TX 78205 | Oil & Gas Operator | May 2025 |
| 134 | Galloway Lone Star, L.L.C. | Tomball, TX 77377 | Oil & Gas Operator | May 2025 |
| 135 | Gec Operating, Inc. | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 136 | Geiser, D. Allen | Portland, TX 78374 | Oil & Gas Operator | Oct 2005 |
| 137 | Gemarmi Inc. | Cypress, TX 77433 | Oil & Gas Operator | May 2025 |
| 138 | Genesis Producing Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2007 |
| 139 | Geodominion Petroleum | Corpus Chrsti, TX 78403 | Oil & Gas Operator | May 2012 |
| 140 | Gilster, Ralph R. III | Victoria, TX 77901 | Oil & Gas Operator | Jun 2004 |
| 141 | Glori Energy Holdings Inc. | Houston, TX 77053 | Oil & Gas Operator | Jan 2017 |
| 142 | Glori Energy Production LLC | Houston, TX 77027 | Oil & Gas Operator | Apr 2018 |
| 143 | Goldking Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 144 | Goldston Oil Corporation | Houston, TX 77257 | Oil & Gas Operator | May 2025 |
| 145 | Goodrich Oil Company | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2001 |
| 146 | Great Bay Operations, LLC | Portsmouth, NH 03801 | Oil & Gas Operator | Nov 2016 |
| 147 | Greenbrier Oper. Co. | Dallas, TX 75229 | Oil & Gas Operator | Feb 2001 |
| 148 | Greta Operating Company LLC | Refugio, TX 78377 | Oil & Gas Operator | May 2025 |
| 149 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 150 | H & D Operating Company | Refugio, TX 78377 | Oil & Gas Operator | May 2015 |
| 151 | H-M Resource Management, Inc. | Houston, TX 77055 | Oil & Gas Operator | Feb 2023 |
| 152 | Harper Hefte, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | May 2025 |
| 153 | Hart Petroleum Services, Inc | Robstown, TX 78380 | Oil & Gas Operator | May 2025 |
| 154 | Harvey Brothers Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Jul 2004 |
| 155 | Harvey, Mike W. Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Aug 2003 |
| 156 | Hawn Brothers | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2003 |
| 157 | Heritage Operating Co., Inc. The | Stafford, TX 77497 | Oil & Gas Operator | May 1997 |
| 158 | High Plains Gas Systems, Inc. | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 159 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | May 2025 |
| 160 | Hughes Legacy LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2022 |
| 161 | Hunter Petroleum Inc. | Alice, TX 78333 | Oil & Gas Operator | May 2014 |
| 162 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | May 2025 |
| 163 | Hyquest Energy, Inc. | Midland, TX 79710 | Oil & Gas Operator | Mar 2015 |
| 164 | I.T. Corporation | Arlington, TX 76016 | Oil & Gas Operator | May 2025 |
| 165 | Imperial Oil Company | Houston, TX 77073 | Oil & Gas Operator | Oct 2004 |
| 166 | J G Oil & Gas | Albany, TX 76430 | Oil & Gas Operator | May 2025 |
| 167 | Jamex, Inc. | Lewisville, TX 75067 | Oil & Gas Operator | May 2025 |
| 168 | Jay-Dee Operating Company | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Aug 2000 |
| 169 | Jet Oil Producers | Coldspring, TX 77331 | Oil & Gas Operator | Mar 2008 |
| 170 | Jones, Edwin M. Oil Co. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 171 | Josey Oil Company | Houston, TX 77019 | Oil & Gas Operator | Jul 2006 |
| 172 | Josey Oil Company, LTD. | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 173 | Josey, Lenoir M., Inc. | Houston, TX 77019 | Oil & Gas Operator | Aug 2003 |
| 174 | Joy Resources, Inc. | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 175 | JTB Oil Company, Inc. | Refugio, TX 78377 | Oil & Gas Operator | May 2025 |
| 176 | Jura Energy Operating LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2023 |
| 177 | Kamlok Oil & Gas, Inc. | Houston, TX 77240 | Oil & Gas Operator | Jun 1996 |
| 178 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 179 | Kebo Oil & Gas, Inc. | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 180 | Keen Operating Company, Inc. | Austin, TX 78705 | Oil & Gas Operator | Aug 2001 |
| 181 | Ken Petroleum Corporation | Dallas, TX 75206 | Oil & Gas Operator | Feb 2019 |
| 182 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 183 | Klotzman, M. S. Exploration Co. | Victoria, TX 77903 | Oil & Gas Operator | May 2025 |
| 184 | Kovar Operating, LLC | Victoria, TX 77901 | Oil & Gas Operator | Sep 2021 |
| 185 | L & F Drilling Co., Inc. (1) | Corpus Chrsti, TX 78479 | Oil & Gas Operator | May 2025 |
| 186 | Lamar Oil & Gas, Inc. | Rockport, TX 78381 | Oil & Gas Operator | May 2025 |
| 187 | Lapis Operating, Inc. | Houston, TX 77042 | Oil & Gas Operator | Jul 2015 |
| 188 | Laquey, E. C. | Refugio, TX 78377 | Oil & Gas Operator | Aug 2003 |
| 189 | Laroca Resources, LTD | Austin, TX 78709 | Oil & Gas Operator | May 2025 |
| 190 | Laroco LLP | Woodsboro, TX 78393 | Oil & Gas Operator | Mar 2008 |
| 191 | Live Oak Gas Company | Dallas, TX 75251 | Oil & Gas Operator | May 2025 |
| 192 | Live Oak Reserves, Inc. | Houston, TX 77019 | Oil & Gas Operator | May 2025 |
| 193 | Live Oak/Operations, Inc. | Houston, TX 77019 | Gas Operator | Jul 2011 |
| 194 | Long Trusts, The | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 195 | Lucas Energy, Inc. | Houston, TX 77067 | Oil & Gas Operator | Feb 2017 |
| 196 | Lundberg Operating Corporation | Dallas, TX 75225 | Oil & Gas Operator | Oct 2002 |
| 197 | M-V Company | Refugio, TX 78377 | Oil & Gas Operator | Jun 2004 |
| 198 | M. J. G., Inc. | Alice, TX 78333 | Oil & Gas Operator | Jul 2010 |
| 199 | M.R.M. Operating, Inc. | Midland, TX 79707 | Oil & Gas Operator | Aug 2003 |
| 200 | Maggert Energy Corp. | Spring, TX 77387 | Gas Operator | Jun 1998 |