| 101 | Cannan, Morris | San Antonio, TX 78205 | Oil & Gas Operator | Jul 2025 |
| 102 | Canyon Creek Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2025 |
| 103 | Carburante Exploration Co, LTD. | Granbury, TX 76048 | Oil & Gas Operator | Jul 2025 |
| 104 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 105 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 106 | Carter Exploration Company | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Feb 2015 |
| 107 | Caskids Operating Company | Houston, TX 77027 | Oil & Gas Operator | Jul 2025 |
| 108 | CB Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Nov 2017 |
| 109 | CBN Operating Corp. | Austin, TX 78746 | Oil & Gas Operator | Jul 2025 |
| 110 | Ceniza Petroleum, Inc. | Portland, TX 78374 | Oil & Gas Operator | Jul 2025 |
| 111 | Challenge Operating Inc | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2024 |
| 112 | Chandler Oil & Gas, LLC | Beeville, TX 78102 | Oil & Gas Operator | Jul 2025 |
| 113 | Chaparral (USA) Energy, Inc. | Oklahoma City, OK 73114 | Oil & Gas Operator | Sep 2002 |
| 114 | Chaparral Energy, L.L.C. | Oklahoma City, OK 73142 | Oil & Gas Operator | Jul 2025 |
| 115 | Chass Production Co. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Nov 2020 |
| 116 | Chemily Management Company | Cypress, TX 77429 | Oil & Gas Operator | Apr 2023 |
| 117 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2025 |
| 118 | Chesnutt Oil & Gas, Inc. | Mineral, TX 78125 | Oil & Gas Operator | Jul 2025 |
| 119 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 120 | Chisholm Oil & Gas, LC | Buda, TX 78610 | Oil & Gas Operator | Jul 2025 |
| 121 | Choice Exploration, Inc. | Irving, TX 75063 | Oil & Gas Operator | Jul 2025 |
| 122 | Christico Petroleum Company | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2025 |
| 123 | Christopher Oil & Gas Inc | Fulshear, TX 77441 | Oil & Gas Operator | Apr 2015 |
| 124 | Cico Oil & Gas Company | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 125 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Jul 2025 |
| 126 | Cimarron Engineering Corp. | Kingsville, TX 78364 | Oil & Gas Operator | May 2015 |
| 127 | Cimarron Engineering, LLC | Kingsville, TX 78364 | Oil & Gas Operator | Jul 2025 |
| 128 | Cinco Natural Resources Corp | La Grange, TX 78945 | Oil & Gas Operator | Jul 2025 |
| 129 | Clay Exploration, Inc. | Spring, TX 77387 | Oil & Gas Operator | Jun 2019 |
| 130 | Cliffwood Production Co. | Houston, TX 77090 | Oil & Gas Operator | Aug 2013 |
| 131 | CLR Gauging Corp. | Tuleta, TX 78162 | Oil & Gas Operator | Jul 2025 |
| 132 | CLR Secondary Recovery, LLC | Wichita Falls, TX 76306 | Oil & Gas Operator | Jul 2025 |
| 133 | CML Exploration, LLC | Austin, TX 78746 | Oil & Gas Operator | Jul 2025 |
| 134 | CMS Nomeco Oil & Gas Co. | Jackson, MI 49201 | Oil & Gas Operator | Jan 2015 |
| 135 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 136 | Cobbs Brothers Oil & Gas | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Jun 2009 |
| 137 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Jul 2025 |
| 138 | Cody Energy LLC | Houston, TX 77024 | Oil & Gas Operator | Jun 2020 |
| 139 | Cody Energy, Inc. | Houston, TX 77077 | Oil & Gas Operator | May 2025 |
| 140 | Collins & Ware, Inc. | Midland, TX 79701 | Oil & Gas Operator | Aug 2003 |
| 141 | Cologne Production Company | San Antonio, TX 78209 | Oil & Gas Operator | Nov 2014 |
| 142 | Columbia Gas Development Corp. | Houston, TX 77251 | Oil & Gas Operator | Jun 1996 |
| 143 | Columbus Energy, LLC | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 144 | Comstock Oil & Gas, Inc. | Frisco, TX 75034 | Oil & Gas Operator | Dec 2012 |
| 145 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 146 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 147 | ConocoPhillips Company | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 148 | Continental Exploration LLC | Richardson, TX 75080 | Oil & Gas Operator | Jul 2025 |
| 149 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Jul 2025 |
| 150 | Contract Oil & Gas Service Co. | Tomball, TX 77375 | Oil & Gas Operator | Apr 2007 |
| 151 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 152 | Cook Marshall Operating, Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 1995 |
| 153 | Cordele Development Corporation | San Antonio, TX 78205 | Oil & Gas Operator | Jul 2025 |
| 154 | Corenergy Operating Group, LLC | Houston, TX 77074 | Oil & Gas Operator | Jul 2025 |
| 155 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 156 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 157 | Cox & Perkins Exploration, Inc. | Houston, TX 77057 | Oil & Gas Operator | Jul 2025 |
| 158 | Cross Timbers Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2025 |
| 159 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 160 | Cummins & Walker Oil Co., Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2021 |
| 161 | Cypress E & P Corporation | Leander, TX 78646 | Oil & Gas Operator | Sep 2016 |
| 162 | D90 Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Jul 2025 |
| 163 | Dahco Operating, LLC | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Jul 2025 |
| 164 | Daniels Corporation, The | Seabrook, TX 77586 | Oil & Gas Operator | Jul 2025 |
| 165 | DCDC, Inc. | Midland, TX 79710 | Oil & Gas Operator | Jun 2003 |
| 166 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Apr 2025 |
| 167 | De La Torre Oil & Gas, Inc | McAllen, TX 78501 | Oil & Gas Operator | Jul 2025 |
| 168 | Decker Operating Co., L.L.C. | Houston, TX 77008 | Oil & Gas Operator | Jul 2025 |
| 169 | Deguello Operating LLC | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 170 | Delco Operating Company LP | Houston, TX 77056 | Oil & Gas Operator | May 2020 |
| 171 | Delray Oil, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2025 |
| 172 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 173 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Jul 2025 |
| 174 | Dinero Oil Corporation | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Nov 1999 |
| 175 | Dirks Petroleum Company | Beeville, TX 78104 | Oil & Gas Operator | Jul 2025 |
| 176 | Discovery Energy Corp. CC | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Jul 2025 |
| 177 | Discovery Petroleum, L.L.C. | Alice, TX 78333 | Oil & Gas Operator | Jul 2025 |
| 178 | Dogwood Operating Company, Inc. | Houston, TX 77069 | Oil & Gas Operator | Jul 2025 |
| 179 | Dolphin Petroleum | Alice, TX 78333 | Oil & Gas Operator | Jun 2008 |
| 180 | Dolphin Petroleum, LP | Alice, TX 78333 | Oil & Gas Operator | Jul 2025 |
| 181 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 182 | Donna-Lynne Oil Co. | George West, TX 78022 | Oil & Gas Operator | Jun 2018 |
| 183 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 184 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Jul 2025 |
| 185 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 186 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Jul 2025 |
| 187 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Jul 2025 |
| 188 | East Texas Production MGT. Inc | Athens, TX 75751 | Oil & Gas Operator | Jul 2025 |
| 189 | Edge Petroleum Oper. Co., Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 190 | Eex E&P Company, L.P. | Houston, TX 77060 | Oil & Gas Operator | Jul 2003 |
| 191 | El Paso E&P Company, L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2013 |
| 192 | El Paso Production Oil & Gas Co. | Houston, TX 77252 | Oil & Gas Operator | Jul 2025 |
| 193 | Elliott Oil & Gas Operating Co. | Magnolia, TX 77354 | Oil & Gas Operator | Jul 2025 |
| 194 | Ellstrom Energy Company | Kingwood, TX 77339 | Oil & Gas Operator | Nov 2000 |
| 195 | Ellsworth, H. P. O&G Properties | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Jul 2025 |
| 196 | Encino Exploration, Inc. | George West, TX 78022 | Oil & Gas Operator | Jul 2025 |
| 197 | Enco Exploration Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2020 |
| 198 | Enduring Resources, LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | May 2025 |
| 199 | Energy 2000, Inc. | Reno, NV 89501 | Oil & Gas Operator | Jul 2025 |
| 200 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |