| 1101 | Dale O. Reese, Inc. | | Oil Operator | Jul 1997 |
| 1102 | Dale Operating Company | Dallas, TX 75207 | Oil & Gas Operator | Apr 2026 |
| 1103 | Daleco Resources | | Gas Operator | Dec 2000 |
| 1104 | Dalen Resources Oil & Gas Co | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 1105 | Dallas DRLG. & Development Co. | | Oil & Gas Operator | Apr 1987 |
| 1106 | Dallas Production Company LLC | Dallas, TX 75206 | Oil & Gas Operator | Apr 2026 |
| 1107 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 1108 | Dalnor Corporation | | Oil & Gas Operator | Nov 2010 |
| 1109 | Dalton J. Woods | | Oil & Gas Operator | Dec 1985 |
| 1110 | Damian Oil, Inc. | | Oil & Gas Operator | Dec 2024 |
| 1111 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 1112 | Damson-Franks-McCord-Goodrich | | Oil & Gas Operator | Aug 1984 |
| 1113 | Dan A. Hughes Company | | Oil & Gas Operator | Dec 2005 |
| 1114 | Dan A. Hughes Company, L.P. | Beeville, TX 78104 | Oil & Gas Operator | Jan 2026 |
| 1115 | Dan Owens | | Oil & Gas Operator | Jul 1993 |
| 1116 | Daniel Oil Company | | Oil & Gas Operator | Jan 1983 |
| 1117 | Danny Glass | | Oil Operator | Jan 1987 |
| 1118 | Danos Oil & Gas LLC | | Oil & Gas Operator | Oct 2024 |
| 1119 | Dant Operating Company Inc. | | Oil & Gas Operator | Jan 1989 |
| 1120 | Dantex Oil & Gas, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Aug 2003 |
| 1121 | Dardan Expl Inc-H Edison Ellis | | Oil & Gas Operator | Apr 1990 |
| 1122 | Darsey Operating Corporation | | Oil & Gas Operator | Sep 1990 |
| 1123 | Dave Easom Production Co. Inc. | | Oil & Gas Operator | May 2000 |
| 1124 | Dave'S Production | | Oil Operator | Dec 2024 |
| 1125 | Davenport Production Corp. | | Oil Operator | Sep 1988 |
| 1126 | David A. Robinson | | Oil Operator | Jan 1999 |
| 1127 | David Crow | | Oil & Gas Operator | Nov 1985 |
| 1128 | David Divine Production | | Oil & Gas Operator | Nov 1997 |
| 1129 | David L. Whittington | | Gas Operator | Dec 1998 |
| 1130 | David L. Whittington Inc | | Gas Operator | Sep 2022 |
| 1131 | David Lynn Chiles | | Oil & Gas Operator | Aug 2020 |
| 1132 | David New Operating Co. Inc. | | Oil & Gas Operator | Feb 1999 |
| 1133 | Davis & Davis | | Oil & Gas Operator | Dec 2021 |
| 1134 | Davis & Kaiser Operating, Inc. | | Oil Operator | May 2004 |
| 1135 | Davis And Backus | | Oil Operator | Nov 1999 |
| 1136 | Davis Asset Management, Inc. | Houston, TX 77010 | Oil & Gas Operator | Dec 2004 |
| 1137 | Davis Gulf Coast, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2026 |
| 1138 | Davis Oil Company | Denver, CO 80202 | Oil & Gas Operator | Jun 1988 |
| 1139 | Davis Oil Company-Cox | | Oil & Gas Operator | Aug 1980 |
| 1140 | Davis Petroleum Corp. | Houston, TX 77027 | Oil & Gas Operator | Apr 2026 |
| 1141 | Davis-Goodman Oil Company | | Oil & Gas Operator | Jun 1980 |
| 1142 | Davis-Goodman-Medders | | Oil & Gas Operator | Jun 1980 |
| 1143 | Dawson Exploration, Inc. | | Oil & Gas Operator | Jun 1986 |
| 1144 | Day Dreams Resources, LLC | | Oil & Gas Operator | Jan 2026 |
| 1145 | Day Town Operating, LLC | | Oil & Gas Operator | Jan 2025 |
| 1146 | Daybreak Oil And Gas, Inc. | | Oil & Gas Operator | Dec 2025 |
| 1147 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Apr 2026 |
| 1148 | Daymon Martin | | Oil Operator | Mar 1983 |
| 1149 | DBL DRLG.&Prod. Services, Inc. | | Oil & Gas Operator | Jul 1997 |
| 1150 | DCP Midstream, LLC | | Oil Operator | Jun 2016 |
| 1151 | DCP, Inc. | | Oil & Gas Operator | Jun 1990 |
| 1152 | DDC & T Operating Company, Inc | | Oil & Gas Operator | Jul 2005 |
| 1153 | Dean Enterprises, Inc. | | Oil & Gas Operator | Jun 2019 |
| 1154 | Dean Petroleum | | Oil & Gas Operator | Jun 2000 |
| 1155 | Debbie Carroll | | Oil & Gas Operator | Apr 1999 |
| 1156 | Debeaux - Flores | | Oil & Gas Operator | Jan 2025 |
| 1157 | Deblin Oil & Gas, Inc | | Oil & Gas Operator | Aug 1995 |
| 1158 | Deblin Operating LTD | | Oil & Gas Operator | Jan 1997 |
| 1159 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 1160 | Decker & Associates | | Oil & Gas Operator | Mar 1991 |
| 1161 | Decker Operating Co., L.L.C. | Houston, TX 77008 | Oil & Gas Operator | Apr 2026 |
| 1162 | Deco | Kilgore, TX 75662 | Oil & Gas Operator | Jan 1999 |
| 1163 | Deco Oil Co. | | Oil Operator | Oct 2013 |
| 1164 | Deep South Production | | Oil Operator | Dec 2023 |
| 1165 | Dees Production LLC | | Oil Operator | Dec 2024 |
| 1166 | Dekasco, Inc. | | Oil & Gas Operator | May 1990 |
| 1167 | Delbert A. Dodson | | Oil Operator | Aug 2002 |
| 1168 | Delhi Gas Pipeline Corporation | Palestine, TX 75802 | Oil & Gas Operator | Feb 1998 |
| 1169 | Delmar Operating, Inc. | Houston, TX 77010 | Oil & Gas Operator | Oct 1996 |
| 1170 | Delphi International, Inc. | Tulsa, OK 74104 | Oil Operator | Feb 2026 |
| 1171 | Delta Development Co. Inc. | | Oil & Gas Operator | Dec 1988 |
| 1172 | Delta Energy Resources, Inc. | | Oil & Gas Operator | Jun 1990 |
| 1173 | Delta Expl.& Development Corp. | | Oil & Gas Operator | Jan 2025 |
| 1174 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Apr 2026 |
| 1175 | Delta Operating Company | | Oil Operator | Mar 1987 |
| 1176 | Delta Operating Corporation | | Oil & Gas Operator | Feb 2024 |
| 1177 | Delta Petroleum Corp Of Co | | Oil & Gas Operator | Oct 2010 |
| 1178 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 1179 | Delta Production Services, LLC | | Oil & Gas Operator | Aug 2002 |
| 1180 | Delta Royalties LLC | | Oil & Gas Operator | Dec 2024 |
| 1181 | Deltaus Corporation | | Oil & Gas Operator | Oct 1985 |
| 1182 | Deminex U S Oil Company | | Oil & Gas Operator | Jan 1998 |
| 1183 | Demiran Production, Inc. | | Oil Operator | Mar 2008 |
| 1184 | Dempsey & Rowe | | Oil Operator | Aug 1986 |
| 1185 | Denali Oil & Gas Management LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 1186 | Denbury Management, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Dec 1999 |
| 1187 | Denbury Offshore, Inc. | | Oil & Gas Operator | Nov 2004 |
| 1188 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Apr 2026 |
| 1189 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 1190 | Denex, Inc. | | Oil & Gas Operator | Jul 1983 |
| 1191 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 1192 | Derrick Petroleum Inc | Bladensburg, OH 43005 | Oil & Gas Operator | Dec 2025 |
| 1193 | Desco Oil Company | Houston, TX 77056 | Oil & Gas Operator | Feb 2017 |
| 1194 | Desco-Medders | | Oil & Gas Operator | Jun 1984 |
| 1195 | Desoto Gas Corporation | | Oil & Gas Operator | Oct 1986 |
| 1196 | Desoto Gas Prod Co Inc-Zadeck | | Gas Operator | Jan 1990 |
| 1197 | Desoto Gas Producing Co. Inc | | Oil & Gas Operator | Jan 1990 |
| 1198 | Desoto Oil & Gas Corporation | | Oil & Gas Operator | Dec 1990 |
| 1199 | Desperation Oil & Gas Co. | | Gas Operator | Jan 1989 |
| 1200 | Despot Expl. Inc-Serio Expl Co | | Oil & Gas Operator | Apr 1990 |