| 101 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Nov 2024 |
| 102 | Chestnut Explor. And Prod., Inc. | Dallas, TX 75208 | Oil & Gas Operator | Mar 2025 |
| 103 | Chestnut Petroleum, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Nov 2011 |
| 104 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Mar 2025 |
| 105 | Chinn Exploration Company | Longview, TX 75605 | Oil & Gas Operator | Nov 2015 |
| 106 | Chisos, LTD | Houston, TX 77098 | Oil & Gas Operator | Mar 2025 |
| 107 | Christeve Oil Company, Inc. | Houston, TX 77068 | Oil & Gas Operator | Dec 2022 |
| 108 | Cinron Energy, LLC | Arp, TX 75750 | Oil & Gas Operator | Mar 2025 |
| 109 | Cippele Resources Co. | Longview, TX 75608 | Oil & Gas Operator | May 1994 |
| 110 | Circle-S Energy, LLC | McKinney, TX 75071 | Oil & Gas Operator | Mar 2025 |
| 111 | CL&F Operating LLC | Spring, TX 77389 | Oil & Gas Operator | Dec 2022 |
| 112 | Clark, Richard E., Inc. | Longview, TX 75604 | Oil & Gas Operator | May 2001 |
| 113 | Classic Energy Incorporated | Tyler, TX 75701 | Oil & Gas Operator | Jul 2005 |
| 114 | Classic Oil & Gas, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jan 2004 |
| 115 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 116 | CLR Secondary Recovery, LLC | Wichita Falls, TX 76306 | Oil & Gas Operator | Mar 2025 |
| 117 | CNG Producing Company | New Orleans, LA 70112 | Oil & Gas Operator | Dec 2015 |
| 118 | CNS Energy, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 2010 |
| 119 | Coal Creek Energy, LLC | Overland Park, KS 66221 | Oil Operator | Dec 2019 |
| 120 | Coastal Management Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 121 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 122 | Coates Energy Interests, LTD. | San Antonio, TX 78217 | Oil & Gas Operator | Aug 1997 |
| 123 | Cobalt Energy LLC | Wichita, KS 67202 | Oil & Gas Operator | Nov 2024 |
| 124 | Cole, Frank W Engineering | Dallas, TX 75254 | Oil & Gas Operator | Mar 2006 |
| 125 | Comanche Well Service Corp. | Plano, TX 75093 | Oil & Gas Operator | Mar 2025 |
| 126 | Compass Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2025 |
| 127 | Concord Operating Incorporated | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2008 |
| 128 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 129 | Cook Exploration Co. | Longview, TX 75602 | Oil & Gas Operator | Mar 2025 |
| 130 | Corda Corporation | Wichita Falls, TX 76302 | Oil & Gas Operator | Mar 2025 |
| 131 | Cordillera Texas, L.P. | Greenwood VLG, CO 80111 | Oil & Gas Operator | Sep 2008 |
| 132 | Cory, Kenneth W. LTD. | Bellaire, TX 77401 | Oil & Gas Operator | Mar 2025 |
| 133 | Cotton Valley Operations, Inc. | Longview, TX 75608 | Oil & Gas Operator | Mar 2025 |
| 134 | Cottonwood Resources, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Aug 2003 |
| 135 | Craig, J. E. G. Estate | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 136 | Craton Energy Company II LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2006 |
| 137 | Craton Operating LLC | Bellaire, TX 77401 | Oil & Gas Operator | Mar 2025 |
| 138 | Crescent Pass Energy, LLC | Houston, TX 77070 | Oil & Gas Operator | Mar 2025 |
| 139 | Crestmont Operating LLC | New York, NY 10151 | Oil Operator | Mar 2025 |
| 140 | Cross Creek Energy LLC | Houston, TX 77074 | Oil & Gas Operator | Aug 2013 |
| 141 | Cross Timbers Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 142 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2024 |
| 143 | Culver & Cain Production LLC | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 144 | D & H Production, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2024 |
| 145 | D-S-B Properties, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2014 |
| 146 | D-S-B Properties, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 147 | Daco Oil | Joinerville, TX 75658 | Oil & Gas Operator | Aug 2019 |
| 148 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 149 | Dallas Production Company LLC | Dallas, TX 75206 | Oil & Gas Operator | Mar 2025 |
| 150 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 151 | Danmark Energy Services, Inc. | White Oak, TX 75693 | Oil & Gas Operator | Apr 2021 |
| 152 | Dearing, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2021 |
| 153 | Deco | Kilgore, TX 75662 | Oil & Gas Operator | Jan 1999 |
| 154 | Delek Energy Systems Us Inc | Denver, CO 80202 | Oil & Gas Operator | Oct 2011 |
| 155 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 156 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 157 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Mar 2025 |
| 158 | Donnell Pipe & Supply Co/TX Corp | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2008 |
| 159 | Dorfman Production Company | Beloit, OH 44609 | Oil & Gas Operator | Mar 2025 |
| 160 | Dunbar, Ron, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jan 2012 |
| 161 | Dyersdale Energy, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 162 | Dyersdale Production Co, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 163 | Eason Production Company | Atlanta, TX 75551 | Oil & Gas Operator | May 2007 |
| 164 | East Texas Production MGT. Inc | Athens, TX 75751 | Oil & Gas Operator | Mar 2025 |
| 165 | Eastex Operating, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jun 2003 |
| 166 | Edmonds, Karl F. Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2005 |
| 167 | Eex Corporation | Houston, TX 77060 | Oil & Gas Operator | Feb 2000 |
| 168 | El Paso E&P Company, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2013 |
| 169 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 170 | Ellora LLC | Boulder, CO 80308 | Oil & Gas Operator | Feb 2010 |
| 171 | Elms Oil Company | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 172 | Embassy Well Service, LLC | Carrollton, TX 75011 | Oil & Gas Operator | Mar 2025 |
| 173 | Enbridge Pipelines (Ne Texas) LP | Houston, TX 77002 | Oil & Gas Operator | Jan 2010 |
| 174 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Jan 2025 |
| 175 | Energy 2000, Inc. | Reno, NV 89501 | Oil & Gas Operator | Mar 2025 |
| 176 | Enerquest Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2025 |
| 177 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2024 |
| 178 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 179 | Ensight Resources, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2001 |
| 180 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 181 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 182 | Eurovest Oil & Gas, Inc. | Graham, TX 76450 | Oil & Gas Operator | Mar 2008 |
| 183 | Ev Fleming Enterprises, LLC | Kilgore, TX 75662 | Oil & Gas Operator | Aug 2024 |
| 184 | Excel Oil & Gas, Inc. | Waxahachie, TX 75168 | Oil & Gas Operator | Mar 2025 |
| 185 | Exco Operating Company, LP | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 186 | Exco Partners Operating PTSHP LP | Dallas, TX 75251 | Oil & Gas Operator | Jan 2009 |
| 187 | Exco/Hgi JV Assets, LLC | Dallas, TX 75251 | Oil & Gas Operator | Jun 2014 |
| 188 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 189 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 190 | Exzena Oil Corp. | Tyler, TX 75713 | Oil & Gas Operator | Mar 2025 |
| 191 | Fair Operating, Inc. | Boerne, TX 78015 | Oil & Gas Operator | Mar 2025 |
| 192 | Falcon Resources, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2021 |
| 193 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 194 | First Reserve Oil & Gas Co | Houston, TX 77002 | Oil & Gas Operator | Apr 2000 |
| 195 | Fisher, L. C. Jr. | Longview, TX 75608 | Oil & Gas Operator | May 1993 |
| 196 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 197 | Fort Worth Natural Gas, Inc. | Dallas, TX 75254 | Oil & Gas Operator | Mar 2025 |
| 198 | Fortune Natural Resources Corp. | Houston, TX 77067 | Oil & Gas Operator | Dec 2003 |
| 199 | Fortune Resources LLC | Longview, TX 75604 | Oil & Gas Operator | Mar 2025 |
| 200 | Foundation Energy Management, LLC | Addison, TX 75001 | Oil & Gas Operator | Mar 2025 |