| 101 | CNG Producing Company | New Orleans, LA 70112 | Oil & Gas Operator | Dec 2015 |
| 102 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 103 | Coastal Plains Exploration, LLC | Port Lavaca, TX 77979 | Oil & Gas Operator | Oct 2025 |
| 104 | Coastline Operating, L.L.C. | Houston, TX 77027 | Oil & Gas Operator | Dec 2006 |
| 105 | Cobbs Brothers Oil & Gas | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Jun 2009 |
| 106 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 107 | Collins & Ware, Inc. | Midland, TX 79701 | Oil & Gas Operator | Aug 2003 |
| 108 | Collins Resources, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Mar 2011 |
| 109 | Comstock Oil & Gas, Inc. | Frisco, TX 75034 | Oil & Gas Operator | Dec 2012 |
| 110 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 111 | Concord Operating Incorporated | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2008 |
| 112 | Continental Trend Resources, Inc | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 113 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 114 | Cook Marshall Operating, Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 1995 |
| 115 | Corda Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 116 | Core E & P Corp. | Victoria, TX 77902 | Oil & Gas Operator | Oct 2025 |
| 117 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 118 | Corpus Christi Leaseholds, Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Sep 1996 |
| 119 | Cougar Oil & Gas Co., Inc. | Houston, TX 77269 | Oil & Gas Operator | Mar 2008 |
| 120 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 121 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 122 | Crimson Energy Company, LC | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2004 |
| 123 | Crossroads Petroleum L.L.C. | San Benito, TX 78586 | Oil & Gas Operator | Oct 2025 |
| 124 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 125 | Crystal River Oil & Gas LLC | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jan 2023 |
| 126 | CTR Petroleum, Inc. | Corpus Chrsti, TX 78414 | Oil & Gas Operator | Mar 2015 |
| 127 | Cummins & Walker Oil Co., Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2021 |
| 128 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 129 | D&H-S-S Production Co.,Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Aug 2003 |
| 130 | Dahco Operating, LLC | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2025 |
| 131 | Dale Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 132 | Dalport Oil Corporation | Dallas, TX 75202 | Oil & Gas Operator | Apr 1993 |
| 133 | Davis Gulf Coast, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 134 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 135 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 136 | Decker Operating Co., L.L.C. | Houston, TX 77008 | Oil & Gas Operator | Oct 2025 |
| 137 | Deguello Operating LLC | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 138 | Del Mar Exploration Company | Houston, TX 77006 | Oil & Gas Operator | Jan 2014 |
| 139 | Del Petroleum Corporation | Dallas, TX 75219 | Oil & Gas Operator | Jan 2012 |
| 140 | Delaware Davis Petroleum Corp. | Houston, TX 77056 | Oil & Gas Operator | Jan 2000 |
| 141 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 142 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 143 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Oct 2025 |
| 144 | Dinero Oil Corporation | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Nov 1999 |
| 145 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 146 | Dominion Corporation | Houston, TX 77001 | Oil & Gas Operator | Dec 2010 |
| 147 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 148 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 149 | Double Play Oil & Gas | Portland, TX 78374 | Oil & Gas Operator | Dec 2001 |
| 150 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Oct 2025 |
| 151 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 152 | Drillers Energy Search, Inc | Denver, CO 80202 | Oil & Gas Operator | Aug 1996 |
| 153 | Durango Resources Corp. | Houston, TX 77043 | Oil & Gas Operator | Oct 2025 |
| 154 | Edge Petroleum Oper. Co., Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 155 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 156 | El Paso E&P Company, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2013 |
| 157 | El Paso Field Services Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 158 | Eldon Oil Co. | Three Rivers, TX 78071 | Oil & Gas Operator | Oct 2025 |
| 159 | Electragas, Inc. | Houston, TX 77064 | Oil Operator | Oct 2025 |
| 160 | Ellsworth, H. P. O&G Properties | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Oct 2025 |
| 161 | Encino Exploration, Inc. | George West, TX 78022 | Oil & Gas Operator | Oct 2025 |
| 162 | Enerfin Field Services LLC | Houston, TX 77077 | Oil Operator | Nov 2024 |
| 163 | Energy Acquisitions, Inc. | Spring, TX 77379 | Oil & Gas Operator | Apr 1996 |
| 164 | Energy Transfer Fuel, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 165 | Enexco, Inc. | Dallas, TX 75243 | Oil & Gas Operator | Mar 2017 |
| 166 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 167 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | Jan 2023 |
| 168 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 169 | Evans, Julian | Houston, TX 77024 | Oil & Gas Operator | Nov 1995 |
| 170 | Everest Minerals Corp. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Apr 2001 |
| 171 | Exploration Company, The | San Antonio, TX 78258 | Oil & Gas Operator | Jun 2010 |
| 172 | Export Petroleum Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Oct 2025 |
| 173 | Expro Engineering, Inc. | Fort Worth, TX 76179 | Oil & Gas Operator | Oct 2025 |
| 174 | Extenergy, L.P. | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 175 | Extex Operating Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 176 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 177 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 178 | Ferreira Oil Properties LLC | Carefree, AZ 85377 | Oil Operator | Apr 2014 |
| 179 | Fesco, LTD. | Alice, TX 78332 | Oil Operator | Oct 2025 |
| 180 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 181 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Oct 2025 |
| 182 | Firstrike Energy Corporation | Cleburne, TX 76033 | Oil & Gas Operator | Jan 2025 |
| 183 | Fischer Operating Corporation | Victoria, TX 77902 | Oil & Gas Operator | Jan 1999 |
| 184 | Five-Jab, Inc. | Tomball, TX 77377 | Oil & Gas Operator | Oct 2025 |
| 185 | Flournoy Oil & Gas, Inc. | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 186 | Flournoy Production Co. | Alice, TX 78333 | Oil & Gas Operator | Dec 2002 |
| 187 | Fortune Resources LLC | Longview, TX 75604 | Oil & Gas Operator | Oct 2025 |
| 188 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 189 | Fox, Hewitt B., Inc. | Corpus Chrsti, TX 78411 | Oil & Gas Operator | Oct 2025 |
| 190 | Fredonia Resources Inc. | Longview, TX 75606 | Oil & Gas Operator | Aug 2003 |
| 191 | Frio Exploration Company | Pearland, TX 77588 | Oil & Gas Operator | Dec 2000 |
| 192 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 193 | Gary Oil & Gas | Deer Park, TX 77536 | Oil & Gas Operator | Oct 2025 |
| 194 | Gasper Rice Resources, LTD. | Houston, TX 77068 | Oil & Gas Operator | Oct 2025 |
| 195 | Gcea, LLC | Graham, TX 76450 | Oil & Gas Operator | Mar 2008 |
| 196 | Geiser Operating, Inc. | Portland, TX 78374 | Oil & Gas Operator | Sep 2019 |
| 197 | Geiser, D. Allen | Portland, TX 78374 | Oil & Gas Operator | Oct 2005 |
| 198 | Genesis Producing Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2007 |
| 199 | Geodominion Petroleum | Corpus Chrsti, TX 78403 | Oil & Gas Operator | May 2012 |
| 200 | Gierhart Exploration, Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Apr 1994 |