| 101 | Classic Oil & Gas, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jan 2004 |
| 102 | Classic Operating Co. LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 103 | Clide Oil Corp. | Iraan, TX 79744 | Oil & Gas Operator | Nov 2015 |
| 104 | CLR Secondary Recovery, LLC | Wichita Falls, TX 76306 | Oil & Gas Operator | Oct 2025 |
| 105 | CNS Energy, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 2010 |
| 106 | Cody Energy, Inc. | Houston, TX 77077 | Oil & Gas Operator | Aug 2025 |
| 107 | Comco Of Louisiana, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jun 2000 |
| 108 | Compass Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 109 | Comstock Oil & Gas, Inc. | Frisco, TX 75034 | Oil & Gas Operator | Dec 2012 |
| 110 | Comstock Oil & Gas, LLC | Frisco, TX 75034 | Oil & Gas Operator | Oct 2025 |
| 111 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 112 | Concord Operating Incorporated | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2008 |
| 113 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 114 | Conquest Energy, Inc. | Fort Worth, TX 76116 | Oil & Gas Operator | Oct 2025 |
| 115 | Cook Exploration Co. | Longview, TX 75602 | Oil & Gas Operator | Oct 2025 |
| 116 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 117 | Corsa Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 118 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 119 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 120 | Cotton Valley Resources, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2025 |
| 121 | Covey Park Operating LLC | Dallas, TX 75225 | Oil & Gas Operator | Aug 2019 |
| 122 | Covey Park Resources LLC | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 123 | Cox Resources Corporation | Dallas, TX 75244 | Oil & Gas Operator | Mar 2015 |
| 124 | CR2 Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 125 | Craton Energy Company II LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2006 |
| 126 | Craton Energy Holdings III, LP | Houston, TX 77002 | Oil & Gas Operator | Jul 2009 |
| 127 | Craton Operating LLC | Bellaire, TX 77401 | Oil & Gas Operator | Oct 2025 |
| 128 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 129 | CRD Operating, LLC | Fort Worth, TX 76116 | Oil & Gas Operator | Feb 2021 |
| 130 | Crescent Pass Energy, LLC | Houston, TX 77070 | Oil & Gas Operator | Oct 2025 |
| 131 | Cross Creek Energy LLC | Houston, TX 77074 | Oil & Gas Operator | Aug 2013 |
| 132 | Cross Timbers Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 133 | Crow, David | Shreveport, LA 71106 | Oil & Gas Operator | May 2001 |
| 134 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 135 | Culver & Cain Production LLC | Tyler, TX 75711 | Oil & Gas Operator | Oct 2025 |
| 136 | CX Operating LLC | Dallas, TX 75238 | Oil & Gas Operator | Oct 2025 |
| 137 | Cypress Operating, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Oct 2025 |
| 138 | D & W Trucking Company | De Berry, TX 75639 | Oil Operator | Mar 2003 |
| 139 | D-S-B Properties, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2014 |
| 140 | D90 Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 141 | Daco Oil | Joinerville, TX 75658 | Oil & Gas Operator | Aug 2019 |
| 142 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 143 | Danmark Energy Services, Inc. | White Oak, TX 75693 | Oil & Gas Operator | Apr 2021 |
| 144 | Davis Operating Company | Elysian Field, TX 75642 | Oil & Gas Operator | Oct 2025 |
| 145 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 146 | Dearing, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2021 |
| 147 | Deep Rock Resources, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2025 |
| 148 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 149 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 150 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 151 | Diamond Energy, Inc. | Sherman, TX 75091 | Oil & Gas Operator | Oct 2025 |
| 152 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 153 | Dixie Lake Operating, LLC | Longview, TX 75606 | Gas Operator | Oct 2025 |
| 154 | DJD Drilling Corporation | Graham, TX 76450 | Oil Operator | Jan 2010 |
| 155 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 156 | DNR Oil And Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Aug 2025 |
| 157 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 158 | Donnell Pipe & Supply Co/TX Corp | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2008 |
| 159 | Dorado Operating Inc. | Dallas, TX 75225 | Oil & Gas Operator | Apr 2011 |
| 160 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Oct 2025 |
| 161 | Double L Contractors, LLC | Carthage, TX 75633 | Oil Operator | Oct 2025 |
| 162 | Dove Creek Energy, Inc. | Fort Worth, TX 76121 | Oil & Gas Operator | Oct 2025 |
| 163 | Dowden, T. L. | Henderson, TX 75652 | Oil & Gas Operator | Oct 2025 |
| 164 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 165 | E.C. Production, L.L.C. | Rosenberg, TX 77471 | Oil & Gas Operator | Oct 2025 |
| 166 | Eagle Oil Management, LLC | Shreveport, LA 71106 | Oil & Gas Operator | Oct 2025 |
| 167 | Eason Production Company | Atlanta, TX 75551 | Oil & Gas Operator | May 2007 |
| 168 | East Texas Exploration, LLC | Edmond, OK 73003 | Oil & Gas Operator | Sep 2019 |
| 169 | Eastex Operating, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jun 2003 |
| 170 | Edmonds, Karl F. Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2005 |
| 171 | Eex E&P Company, L.P. | Houston, TX 77060 | Oil & Gas Operator | Jul 2003 |
| 172 | El Paso E&P Company, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2013 |
| 173 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 174 | Elms Oil Company | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 175 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 176 | Encrescent, LLC | Dallas, TX 75205 | Oil & Gas Operator | Oct 2025 |
| 177 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 178 | Endurance Oil & Gas, Inc. | Minden, LA 71055 | Oil & Gas Operator | Oct 2025 |
| 179 | Enduring Resources, LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Jul 2025 |
| 180 | Energetics Inc | Englewood, CO 80155 | Oil & Gas Operator | Aug 1985 |
| 181 | Energy Oil & Gas Corporation | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 182 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 183 | Enerquest Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 184 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 185 | Enpower Resources Inc. | Sugar Land, TX 77479 | Oil & Gas Operator | Oct 2025 |
| 186 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 187 | Ensight Resources, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2001 |
| 188 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 189 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | Jan 2023 |
| 190 | Erso, Inc. | Houston, TX 77002 | Gas Operator | Mar 1995 |
| 191 | Estate Oil & Gas Corp. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2011 |
| 192 | Etopsi Oil And Gas, L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 193 | Evergreen Operating Co., LTD. | McAllen, TX 78502 | Oil & Gas Operator | Oct 2025 |
| 194 | Exco Operating Company, LP | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 195 | Exco Production Company, LP | Dallas, TX 75251 | Oil & Gas Operator | Dec 2009 |
| 196 | Exco/Hgi JV Assets, LLC | Dallas, TX 75251 | Oil & Gas Operator | Jun 2014 |
| 197 | Explo Oil, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 198 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 199 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 200 | F O & G LLC | Pawhuska, OK 74056-5075 | Oil Operator | Apr 2022 |