| 101 | Caltex Energy Co. | Luling, TX 78648 | Oil & Gas Operator | Oct 2025 |
| 102 | Camco Saltwater Transport | George West, TX 78022 | Oil Operator | Feb 2015 |
| 103 | Camco Saltwater Transport,L.L.C. | George West, TX 78022 | Oil Operator | Oct 2025 |
| 104 | Camden Oil & Gas, Inc. | Farmers BRNCH, TX 75234 | Oil & Gas Operator | Dec 2005 |
| 105 | Camden Resources, Inc. | Farmers BRNCH, TX 75234 | Oil & Gas Operator | Apr 2008 |
| 106 | Camden Resources, LLC | Blanchard, OK 73010 | Oil & Gas Operator | Dec 2015 |
| 107 | Camelot Oil And Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2003 |
| 108 | Cantu Operating, LLC | McAllen, TX 78504 | Oil Operator | Oct 2025 |
| 109 | Canyon Creek Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 110 | Capital Star Oil & Gas, Inc. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 111 | Carrizo Exploration, Inc. | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Aug 2016 |
| 112 | Carrizo Oil & Gas, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 113 | Carter Exploration Company | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Feb 2015 |
| 114 | Caskids Operating Company | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 115 | Caza Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 116 | CCGM Exploration & Prod.,L.C. | Austin, TX 78738 | Oil & Gas Operator | Oct 2025 |
| 117 | Ceniza Petroleum, Inc. | Portland, TX 78374 | Oil & Gas Operator | Oct 2025 |
| 118 | Central Energy Producing Company | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2003 |
| 119 | Central Texas Operating, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Oct 2025 |
| 120 | Cerberus Engineering, LLC | San Antonio, TX 78209 | Oil & Gas Operator | Oct 2025 |
| 121 | Champlin Exploration, Inc. | Enid, OK 73702 | Oil & Gas Operator | Jul 2025 |
| 122 | Chandler Oil & Gas, LLC | Beeville, TX 78102 | Oil & Gas Operator | Oct 2025 |
| 123 | Chaparosa Production Company,Inc | Freer, TX 78357 | Oil & Gas Operator | Oct 2025 |
| 124 | Chapco, Inc. | Benavides, TX 78341 | Oil & Gas Operator | Oct 2025 |
| 125 | Chesapeake Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Jun 2025 |
| 126 | Chesnutt Oil & Gas, Inc. | Mineral, TX 78125 | Oil & Gas Operator | Oct 2025 |
| 127 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 128 | Christeve Oil Company, Inc. | Houston, TX 77068 | Oil & Gas Operator | Dec 2022 |
| 129 | Chroma Operating, Inc. | Washington, DC 20036 | Oil & Gas Operator | Jun 2016 |
| 130 | Chumley, George Estate Of | Alice, TX 78333 | Oil & Gas Operator | Oct 2025 |
| 131 | Cimarex Energy Co. Of Colorado | Midland, TX 79706 | Oil & Gas Operator | Oct 2025 |
| 132 | Cimarron Engineering Corp. | Kingsville, TX 78364 | Oil & Gas Operator | May 2015 |
| 133 | Cimarron Engineering, LLC | Kingsville, TX 78364 | Oil & Gas Operator | Oct 2025 |
| 134 | Cinco Natural Resources Corp | La Grange, TX 78945 | Oil & Gas Operator | Oct 2025 |
| 135 | Citrus Energy Corporation | Castle Rock, CO 80104 | Oil & Gas Operator | Mar 2020 |
| 136 | Claron Corporation | Houston, TX 77219 | Oil & Gas Operator | Oct 2025 |
| 137 | Clay Exploration, Inc. | Spring, TX 77387 | Oil & Gas Operator | Jun 2019 |
| 138 | Cliffwood Production Co. | Houston, TX 77090 | Oil & Gas Operator | Aug 2013 |
| 139 | CM TX Production, LLC | Lakewood, CO 80228 | Oil & Gas Operator | Feb 2023 |
| 140 | Coastal Oil & Gas Corporation | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 141 | Coastal Shoreline Corp. | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Aug 2003 |
| 142 | Coates Energy Trust | San Antonio, TX 78209 | Oil & Gas Operator | Aug 2008 |
| 143 | Columbia Gas Development Corp. | Houston, TX 77251 | Oil & Gas Operator | Jun 1996 |
| 144 | Columbus Energy, LLC | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 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 | Continental Exploration LLC | Richardson, TX 75080 | Oil & Gas Operator | Oct 2025 |
| 148 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 149 | Continental Trend Resources, Inc | Oklahoma City, OK 73126 | Oil & Gas Operator | Oct 2025 |
| 150 | Cordele Development Corporation | San Antonio, TX 78205 | Oil & Gas Operator | Oct 2025 |
| 151 | Coronado Energy E&P Company, LLC | Houston, TX 77252 | Oil & Gas Operator | Dec 2010 |
| 152 | Coronado Minerals, LLC | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 153 | Costilla Energy Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 154 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 155 | Cotton, W. L. | Hebbronville, TX 78361 | Oil & Gas Operator | Mar 1996 |
| 156 | Cotton, W.L. Gems & Minerals LTD | Hebbronville, TX 78361 | Oil & Gas Operator | May 2000 |
| 157 | Cox & Perkins Exploration, Inc. | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 158 | Cox Exploration, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Nov 1999 |
| 159 | Crawford Energy Operating Co | Houston, TX 77056 | Oil & Gas Operator | Aug 2008 |
| 160 | Crest Resources & Expl. Corp. | Houston, TX 77079 | Oil & Gas Operator | Dec 1998 |
| 161 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 162 | Crossroads Petroleum L.L.C. | San Benito, TX 78586 | Oil & Gas Operator | Oct 2025 |
| 163 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 164 | CTR Petroleum, Inc. | Corpus Chrsti, TX 78414 | Oil & Gas Operator | Mar 2015 |
| 165 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | Oct 2025 |
| 166 | Cummins & Walker Oil Co., Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2021 |
| 167 | Cymri Corporation, The | Houston, TX 77057 | Oil & Gas Operator | Mar 2008 |
| 168 | Cymri, L.L.C. | Houston, TX 77042 | Oil & Gas Operator | Oct 2025 |
| 169 | D & B Energy Corporation | San Antonio, TX 78264 | Oil Operator | Oct 2025 |
| 170 | D & P Operating & Prod. Corp. | Cedar Park, TX 78613 | Oil & Gas Operator | Dec 2003 |
| 171 | D. O. G. Operating, LLC | Port Aransas, TX 78373 | Oil & Gas Operator | Oct 2025 |
| 172 | D.Y. Exploration, Inc. | Boise, ID 83705 | Oil & Gas Operator | Oct 2025 |
| 173 | Daf Operating, LLC | Houston, TX 77005 | Oil & Gas Operator | Oct 2025 |
| 174 | Dakota Oil Company | Hebbronville, TX 78361 | Oil & Gas Operator | Oct 2025 |
| 175 | Dale Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 176 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 177 | Dallas Petroleum Group, LLC | Dallas, TX 75379 | Oil & Gas Operator | Oct 2025 |
| 178 | Dantex Oil & Gas, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Aug 2003 |
| 179 | Dark Horse Producing Of TX, L.P. | Alice, TX 78333 | Oil & Gas Operator | Oct 2025 |
| 180 | Dartex Energy Corporation | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 181 | Davis Petroleum Corp. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 182 | Davis, Tommy | Hebbronville, TX 78361 | Oil & Gas Operator | Jun 1995 |
| 183 | Daystar Operating Company, LLC | Austin, TX 78750 | Oil & Gas Operator | Apr 2008 |
| 184 | Del Petroleum Corporation | Dallas, TX 75219 | Oil & Gas Operator | Jan 2012 |
| 185 | Delaware Davis Petroleum Corp. | Houston, TX 77056 | Oil & Gas Operator | Jan 2000 |
| 186 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 187 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 188 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 189 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Oct 2025 |
| 190 | Dewbre, Jerry C., Trustee | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Oct 2025 |
| 191 | Diamondback Operating, LP | Tulsa, OK 74132 | Gas Operator | Oct 2025 |
| 192 | Dinero Oil Corporation | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Nov 1999 |
| 193 | Dirks, R.W. Pet. Eng. Inc. | Tuleta, TX 78162 | Oil & Gas Operator | Jul 1999 |
| 194 | Dirnett, Inc. | Tuleta, TX 78162 | Oil & Gas Operator | Oct 2025 |
| 195 | Discorbis Oil Company | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2019 |
| 196 | Discovery Energy Corp. CC | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2025 |
| 197 | Discovery Petroleum, L.L.C. | Alice, TX 78333 | Oil & Gas Operator | Oct 2025 |
| 198 | DKW Energy, Inc. | Sherman Oaks, CA 91403 | Oil & Gas Operator | Oct 2025 |
| 199 | DML Exploration, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2025 |
| 200 | Dogwood Operating Company, Inc. | Houston, TX 77069 | Oil & Gas Operator | Oct 2025 |