| 101 | Coastal Plains Energy Inc | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2025 |
| 102 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 103 | Cole, Frank W Engineering | Dallas, TX 75254 | Oil & Gas Operator | Mar 2006 |
| 104 | Colotex Operating, LLC | Aurora, CO 80015 | Oil & Gas Operator | Oct 2025 |
| 105 | Comanche Well Service Corp. | Plano, TX 75093 | Oil & Gas Operator | Oct 2025 |
| 106 | Concho Oilfield Service, Inc. | Albany, TX 76430 | Oil & Gas Operator | Apr 2013 |
| 107 | Continental Export Corporation | Bowie, TX 76230 | Oil & Gas Operator | Sep 2013 |
| 108 | Cooper Oil & Gas, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Oct 2025 |
| 109 | Corda Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 110 | Corpening, Joe F. | Bowie, TX 76230 | Oil & Gas Operator | Oct 2013 |
| 111 | Cox, Lee Investments Inc. | Mineral Wells, TX 76067 | Oil & Gas Operator | Oct 2025 |
| 112 | Creswell, R.G. | Graham, TX 76450 | Oil & Gas Operator | Feb 2013 |
| 113 | Crimson Energy Company, LC | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2004 |
| 114 | Crimson Exploration Inc. | Houston, TX 77060 | Oil & Gas Operator | Apr 2006 |
| 115 | Crimson Exploration Oper., Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 116 | Cromeens Petroleum, Inc. | Mineral Wells, TX 76067 | Oil & Gas Operator | Sep 1996 |
| 117 | Crossbow Resources, LLC | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 118 | Crown Equipment Co. | Weatherford, TX 76086 | Oil & Gas Operator | Oct 2025 |
| 119 | Crystal River Oil & Gas LLC | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jan 2023 |
| 120 | Culebra Oil & Gas Company | Dallas, TX 75225 | Oil & Gas Operator | Dec 2000 |
| 121 | Culebra Oil & Gas LLC | Kerrville, TX 78028 | Oil & Gas Operator | Oct 2025 |
| 122 | Cumberland Petroleum, Inc. II | Weatherford, TX 76086 | Oil & Gas Operator | May 1997 |
| 123 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | Oct 2025 |
| 124 | D & R Enterprises | Eastland, TX 76448 | Oil & Gas Operator | Oct 2020 |
| 125 | D-Bar Leasing, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Apr 2022 |
| 126 | D. A. B. Oil Service, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Nov 2012 |
| 127 | D.J. & T. Energy | Abilene, TX 79601 | Oil & Gas Operator | Oct 2025 |
| 128 | Dabb Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Aug 2020 |
| 129 | Dahab Energy Inc. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 130 | Dallas Production Company LLC | Dallas, TX 75206 | Oil & Gas Operator | Oct 2025 |
| 131 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 132 | Darley Enterprises, Inc. | Brownwood, TX 76801 | Oil & Gas Operator | Jan 2012 |
| 133 | Dart Oil & Gas Corporation | Mason, MI 48854 | Oil & Gas Operator | Jun 2018 |
| 134 | Dartex Energy Inc | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 135 | Dedica Energy Corporation | Mattoon, IL 61938 | Oil & Gas Operator | Mar 2008 |
| 136 | Delta Oil & Gas Company | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2003 |
| 137 | Delta Oil & Gas LTD. | Breckenridge, TX 76424 | Oil & Gas Operator | Oct 2025 |
| 138 | Demoss, L. V. | Graham, TX 76450 | Oil & Gas Operator | May 2004 |
| 139 | Denoco Inc. | Plano, TX 75086 | Oil & Gas Operator | Mar 2008 |
| 140 | Denton Exploration, Inc. | Dallas, TX 75219 | Oil & Gas Operator | Oct 2025 |
| 141 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 142 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 143 | Devon Gas Services, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 2015 |
| 144 | Diamond S Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Oct 2025 |
| 145 | Dimock Operating Company | Frisco, TX 75034 | Oil & Gas Operator | Oct 2025 |
| 146 | Dodson Prairie Oil & Gas LLC | San Antonio, TX 78205 | Gas Operator | Oct 2025 |
| 147 | Dooley, Jeff | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2012 |
| 148 | Dorfman Production Company | Beloit, OH 44609 | Oil & Gas Operator | Oct 2025 |
| 149 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Oct 2025 |
| 150 | Double U Oil Co., LTD. | San Antonio, TX 78217 | Oil & Gas Operator | May 2000 |
| 151 | Dove Creek Energy, Inc. | Fort Worth, TX 76121 | Oil & Gas Operator | Oct 2025 |
| 152 | Dowell Oil & Gas | Stephenville, TX 76401 | Oil & Gas Operator | Oct 2025 |
| 153 | Draco Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 154 | Drennan, D. E. | Graham, TX 76450 | Oil & Gas Operator | Dec 2011 |
| 155 | Drillogix Exploration LLC | Breckenridge, TX 76424 | Oil Operator | Oct 2025 |
| 156 | Dry Fork Production Co | Wichita Falls, TX 76301 | Oil Operator | Apr 2003 |
| 157 | Dry Fork Production Co., LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 158 | Dte Gas Resources, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2007 |
| 159 | Dte Gas Resources, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2014 |
| 160 | Dunlap Exploration, Inc. | Fort Worth, TX 76101 | Oil & Gas Operator | Nov 2016 |
| 161 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Oct 2025 |
| 162 | E.C. Hindman Oil And Gas | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 163 | Eagle Energy Acquisitions LP | Houston, TX 77002 | Oil & Gas Operator | Aug 2014 |
| 164 | Eagle Hydrocarbons (Texas) Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 165 | Eagle Hydrocarbons Inc. | Houston, TX 77079 | Oil & Gas Operator | Jun 2020 |
| 166 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 167 | Eagleridge Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | Oct 2025 |
| 168 | Earth Science Exploration, Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2012 |
| 169 | Echo Production Inc | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 170 | El Ran, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Oct 2025 |
| 171 | El Reno Energy, LLC | Granbury, TX 76048 | Oil & Gas Operator | Oct 2025 |
| 172 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 173 | Energy Resource & Develop., Corp | Rockwall, TX 75087 | Oil & Gas Operator | Jun 1998 |
| 174 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 175 | Energy Well Service, Inc. | Stephenville, TX 76401 | Oil & Gas Operator | Oct 2004 |
| 176 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 177 | Engas Corporation | Jacksboro, TX 76458 | Oil & Gas Operator | May 2008 |
| 178 | Enr Operating, LLC | Eunice, NM 88231 | Oil & Gas Operator | Oct 2025 |
| 179 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 180 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 181 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 182 | Eratz Investments Inc. | Dallas, TX 75240 | Oil & Gas Operator | Oct 2025 |
| 183 | Ernmar Investments, Inc. | Edmond, OK 73083 | Oil & Gas Operator | Oct 2025 |
| 184 | Erwin Operating | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 185 | Erwin, James D. | Dallas, TX 75225 | Oil & Gas Operator | Nov 1993 |
| 186 | Esg Resources LLC | Dallas, TX 75231 | Oil & Gas Operator | Oct 2025 |
| 187 | Evarado Oil Company | Strawn, TX 76475 | Oil & Gas Operator | Oct 2025 |
| 188 | Evarado Oil, LLC | Strawn, TX 76475 | Oil & Gas Operator | Oct 2025 |
| 189 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 190 | Exorare Energy, Inc. | Dallas, TX 75218 | Oil & Gas Operator | Oct 2025 |
| 191 | Exp, Inc. | Dallas, TX 75244 | Oil & Gas Operator | May 2003 |
| 192 | F & R Oil Co. | Dallas, TX 75205 | Oil & Gas Operator | May 2005 |
| 193 | Fagadau Energy Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2006 |
| 194 | Fairway Resources Operating, LLC | Southlake, TX 76092 | Oil & Gas Operator | Aug 2022 |
| 195 | Federal Energy Development Co. | Dallas, TX 75205 | Oil & Gas Operator | Mar 2011 |
| 196 | Felderhoff Production Company | Muenster, TX 76252 | Oil & Gas Operator | Oct 2025 |
| 197 | Foag, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jun 2022 |
| 198 | Fossil Operating, Inc. | Dallas, TX 75238 | Oil & Gas Operator | Oct 2025 |
| 199 | Four Square Production, L.L.C. | Houston, TX 77079 | Oil & Gas Operator | Aug 2004 |
| 200 | Franklin, J.W. Oil Operator | | Oil & Gas Operator | Nov 2001 |