| 101 | Cimarex Energy Co Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Mar 2025 |
| 102 | Cimarron Engineering Corp. | Kingsville, TX 78364 | Oil & Gas Operator | May 2015 |
| 103 | Citation Oil & Gas Corp. | Houston, TX 77269 | Oil & Gas Operator | Mar 2025 |
| 104 | CML Exploration, LLC | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 105 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 106 | Cockburn Oil Corporation | Lubbock, TX 79493 | Oil & Gas Operator | Jul 2005 |
| 107 | Cody Energy LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2020 |
| 108 | Cody Energy, Inc. | Houston, TX 77077 | Oil & Gas Operator | Jan 2025 |
| 109 | Comet Oil & Gas, Inc. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2025 |
| 110 | Comet Production | Conroe, TX 77305 | Oil Operator | Mar 2025 |
| 111 | Concord Operating Incorporated | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2008 |
| 112 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 113 | Cooper Oil & Gas, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2025 |
| 114 | Core E & P Corp. | Victoria, TX 77902 | Oil & Gas Operator | Mar 2025 |
| 115 | Corum Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 116 | Costa Energy, LLC | Irving, TX 75063 | Oil & Gas Operator | Mar 2025 |
| 117 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 118 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 119 | Crawford Energy Operating Co | Houston, TX 77056 | Oil & Gas Operator | Aug 2008 |
| 120 | Crawford Hughes Operating Co. | The Woodlands, TX 77380 | Oil & Gas Operator | Mar 2025 |
| 121 | Crestmont Operating LLC | New York, NY 10151 | Oil Operator | Mar 2025 |
| 122 | Crimson Exploration Oper., Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2019 |
| 123 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2024 |
| 124 | Csa Exploration Company, Inc. | Houston, TX 77027 | Oil & Gas Operator | Aug 2003 |
| 125 | CTL Oil & Gas Corporation | Buchanan Dam, TX 78609 | Oil & Gas Operator | Nov 2020 |
| 126 | CWC Oil & Gas, LLC | Abilene, TX 79608 | Oil & Gas Operator | Mar 2025 |
| 127 | D & D Oil Company | Dayton, TX 77535 | Oil & Gas Operator | Mar 2025 |
| 128 | D J Production | Pasadena, TX 77502 | Oil & Gas Operator | Mar 2025 |
| 129 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Mar 2025 |
| 130 | Dartex Energy Corporation | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 131 | Davis, Roland C. | Hardin, TX 77561 | Oil & Gas Operator | May 1997 |
| 132 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Mar 2025 |
| 133 | De-Vac Inc. | Daisetta, TX 77533 | Oil Operator | Mar 2025 |
| 134 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Mar 2025 |
| 135 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 136 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 137 | Devon Energy Operating Co., L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2009 |
| 138 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2025 |
| 139 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Mar 2025 |
| 140 | Diamond S Masada LLC | Magnolia, TX 77354 | Oil & Gas Operator | Mar 2025 |
| 141 | DJH Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 142 | Doggy Oil Corp | Decatur, GA 30031 | Oil & Gas Operator | Mar 2025 |
| 143 | Dogwood Operating Company, Inc. | Houston, TX 77069 | Oil & Gas Operator | Mar 2025 |
| 144 | Dominion Corporation | Houston, TX 77001 | Oil & Gas Operator | Dec 2010 |
| 145 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 146 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 147 | Dorough, Lee Operations | Orlando, FL 32801 | Oil & Gas Operator | Mar 2025 |
| 148 | Douglas Petroleum Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2010 |
| 149 | Draco Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 150 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 151 | Drum Oil & Gas, Inc. | Houston, TX 77082 | Oil & Gas Operator | Mar 2025 |
| 152 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 153 | DSTJ Corporation | Montgomery, TX 77316 | Oil & Gas Operator | Mar 2001 |
| 154 | DSW Production Corp. | Houston, TX 77265 | Oil & Gas Operator | Mar 2025 |
| 155 | Duncan Energy LLC | Dallas, TX 75231 | Oil & Gas Operator | Mar 2025 |
| 156 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Mar 2025 |
| 157 | E & B Equipment | Liberty, TX 77575 | Oil & Gas Operator | Feb 2010 |
| 158 | Ecc Energy Corporation | Dewey, OK 74029 | Oil & Gas Operator | Feb 2020 |
| 159 | Edge Petroleum Oper. Co., Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 160 | Edp Management Company | Houston, TX 77056 | Oil & Gas Operator | Jul 2018 |
| 161 | Edwards Petroleum Company | Houston, TX 77092 | Oil & Gas Operator | Aug 2003 |
| 162 | Elliott Oil & Gas Company | The Woodlands, TX 77380 | Oil & Gas Operator | Sep 2006 |
| 163 | Elp Production Company LLC | Dallas, TX 75287 | Oil Operator | Mar 2025 |
| 164 | Enco Resources Inc. | Kingwood, TX 77325 | Oil & Gas Operator | Mar 2025 |
| 165 | Endeavor Natural Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2015 |
| 166 | Endeavor Natural Gas, LP | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 167 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 168 | Energy Oil & Gas Corporation | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 169 | Energy Reserves Group LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2018 |
| 170 | Energy Transfer Crude Marketing LLC | Houston, TX 77002 | Oil Operator | Dec 2024 |
| 171 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2024 |
| 172 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 173 | Erg Operating Company Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 2006 |
| 174 | Erg Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2015 |
| 175 | Eros Operating LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Mar 2025 |
| 176 | Estes Operating, Inc. | San Antonio, TX 78210 | Oil & Gas Operator | Mar 2002 |
| 177 | Estes Operating, LLC | La Porte, TX 77571 | Oil & Gas Operator | Mar 2025 |
| 178 | Etm Operating Company, Inc. | Houston, TX 77079 | Oil Operator | Feb 2009 |
| 179 | Etoco Incorporated | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 180 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 181 | Famcor Oil, Inc. | Scottsdale, AZ 85260 | Oil & Gas Operator | Sep 2020 |
| 182 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 183 | Faulconer Vernon E Inc | Tyler, TX 75711 | Oil & Gas Operator | Jan 2025 |
| 184 | Felderhoff Production Company | Muenster, TX 76252 | Oil & Gas Operator | Mar 2025 |
| 185 | Finley Oil Company, LLC | Liberty, TX 77575 | Oil Operator | Mar 2025 |
| 186 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Mar 2025 |
| 187 | First Hardin Corp. | Fulshear, TX 77441 | Oil & Gas Operator | Nov 1994 |
| 188 | Five-Jab, Inc. | Tomball, TX 77377 | Oil & Gas Operator | Mar 2025 |
| 189 | Flare Oil Inc | Rockport, TX 78382 | Oil & Gas Operator | Mar 2025 |
| 190 | Foothills Texas, Inc. | Houston, TX 77269 | Oil & Gas Operator | Aug 2019 |
| 191 | Forcenergy Onshore Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2012 |
| 192 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 193 | Forney & McCombs | Houston, TX 77056 | Oil & Gas Operator | Jan 1998 |
| 194 | Fort Apache Energy, Inc. | Boerne, TX 78015 | Oil & Gas Operator | Mar 2025 |
| 195 | Fortune Resources LLC | Longview, TX 75604 | Oil & Gas Operator | Mar 2025 |
| 196 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Mar 2025 |
| 197 | Frio Exploration Company | Pearland, TX 77588 | Oil & Gas Operator | Dec 2000 |
| 198 | Fullerton Energy Corporation | Dallas, TX 75230 | Oil & Gas Operator | Apr 2002 |
| 199 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 200 | G.A.P. Production LLC | Sourlake, TX 77659 | Oil Operator | Mar 2025 |