| 1201 | Demiran Production, Inc. | | Oil Operator | Mar 2008 |
| 1202 | Dempsey & Rowe | | Oil Operator | Aug 1986 |
| 1203 | Denali Oil & Gas Management LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 1204 | Denbury Management, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Dec 1999 |
| 1205 | Denbury Offshore, Inc. | | Oil & Gas Operator | Nov 2004 |
| 1206 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2025 |
| 1207 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 1208 | Denex, Inc. | | Oil & Gas Operator | Jul 1983 |
| 1209 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 1210 | Derrick Petroleum Inc | Bladensburg, OH 43005 | Oil & Gas Operator | Dec 2024 |
| 1211 | Desco Oil Company | Houston, TX 77056 | Oil & Gas Operator | Feb 2017 |
| 1212 | Desco-Medders | | Oil & Gas Operator | Jun 1984 |
| 1213 | Desoto Gas Corporation | | Oil & Gas Operator | Oct 1986 |
| 1214 | Desoto Gas Prod Co Inc-Zadeck | | Gas Operator | Jan 1990 |
| 1215 | Desoto Gas Producing Co. Inc | | Oil & Gas Operator | Jan 1990 |
| 1216 | Desoto Oil & Gas Corporation | | Oil & Gas Operator | Dec 1990 |
| 1217 | Desperation Oil & Gas Co. | | Gas Operator | Jan 1989 |
| 1218 | Despot Expl. Inc-Serio Expl Co | | Oil & Gas Operator | Apr 1990 |
| 1219 | Despot Exploration, Inc. | | Oil & Gas Operator | Apr 1990 |
| 1220 | Despot Production Company | | Oil & Gas Operator | May 1983 |
| 1221 | Despot, Inc. | | Oil & Gas Operator | Mar 1983 |
| 1222 | Destin Operating Company, Inc. | | Oil & Gas Operator | Jan 2023 |
| 1223 | Destin Resources LLC | | Gas Operator | Jul 2018 |
| 1224 | Devon Corporation | | Oil Operator | Oct 1981 |
| 1225 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 1226 | Devon Energy Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2009 |
| 1227 | Devon Energy Operating Co., L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2009 |
| 1228 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 1229 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 1230 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 1231 | Dew Oil And Gas Co.,Inc. | | Oil & Gas Operator | Dec 1989 |
| 1232 | Dewco Oil | | Oil Operator | Jun 1996 |
| 1233 | Dewey E. Williams | | Oil Operator | Nov 1978 |
| 1234 | Dewey White Etal | | Oil & Gas Operator | Dec 1987 |
| 1235 | Dewey Williams | | Oil Operator | Mar 1992 |
| 1236 | Dews Production LLC | Magnolia, AR 71753 | Oil & Gas Operator | Jan 2025 |
| 1237 | Dexco, Inc. | | Oil & Gas Operator | May 1990 |
| 1238 | DGH Petroleum, Inc. | | Oil & Gas Operator | Aug 2011 |
| 1239 | Di Energy Inc. | Houston, TX 77067 | Oil & Gas Operator | Jan 2004 |
| 1240 | Diablo Oil Corp. | | Oil & Gas Operator | Apr 1989 |
| 1241 | Diamar Oil Company, Inc. | | Oil Operator | Nov 1983 |
| 1242 | Diamex Company | | Oil & Gas Operator | Oct 1982 |
| 1243 | Diamond D Operating | | Oil & Gas Operator | Apr 1995 |
| 1244 | Diamond Drilling Co. | | Oil Operator | Apr 1983 |
| 1245 | Diamond S Operating Co. | | Oil & Gas Operator | Oct 1992 |
| 1246 | Diamond Shamrock Corp | Amarillo, TX 79105 | Oil & Gas Operator | Jan 1987 |
| 1247 | Diamond Shamrock Expl. Co. | | Oil & Gas Operator | Jun 1987 |
| 1248 | Diasu Oil & Gas Co., Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 1249 | Dilligas, Inc. | | Oil Operator | May 1990 |
| 1250 | Dimension Energy Co., L.L.C. | | Oil & Gas Operator | Dec 2024 |
| 1251 | Discovery Energy, LLC | | Oil Operator | Jan 2007 |
| 1252 | Discovery Operating, LLC | | Oil & Gas Operator | Oct 2023 |
| 1253 | Discus Oil Corporation | | Oil & Gas Operator | Dec 2002 |
| 1254 | Ditta Exploration Co., Inc. | | Oil & Gas Operator | Feb 1990 |
| 1255 | Diversified Energy Investments | | Oil & Gas Operator | May 2009 |
| 1256 | Diversified Natural Res., Inc. | | Oil Operator | May 2000 |
| 1257 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Dec 2025 |
| 1258 | Divine'S Service & Repairs Inc | | Oil & Gas Operator | Mar 1997 |
| 1259 | Dixie Operating Company | Spring, TX 77379 | Oil & Gas Operator | Dec 2002 |
| 1260 | Dixie Well Service, Inc. | | Oil & Gas Operator | Jul 1995 |
| 1261 | Dixon Management Corp. | | Oil & Gas Operator | May 1984 |
| 1262 | DKM Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2011 |
| 1263 | DLB Oil & Gas, Inc. | Big Lake, TX 76932 | Oil & Gas Operator | Dec 2025 |
| 1264 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Sep 2025 |
| 1265 | Dna Petroleum Inc. | | Oil Operator | Dec 2004 |
| 1266 | Docherty Operating, L.L.C. | | Oil Operator | Dec 2024 |
| 1267 | Dome De Sel LLC | | Oil & Gas Operator | Nov 2024 |
| 1268 | Dome Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2016 |
| 1269 | Domestic Energy Corporation | | Oil Operator | Jan 1988 |
| 1270 | Domestic Oil Producers,Inc. | | Oil Operator | Oct 1998 |
| 1271 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 1272 | Dominion Midstream Services, LP | | Oil Operator | Dec 2006 |
| 1273 | Dominion Minerals Corporation | Houston, TX 77014 | Oil & Gas Operator | Nov 2009 |
| 1274 | Don G. Wiley, Jr. | | Oil Operator | Dec 1979 |
| 1275 | Don Townes | | Oil Operator | Sep 2000 |
| 1276 | Don W. Holcomb | | Oil Operator | Feb 1996 |
| 1277 | Don Webb | | Oil Operator | Mar 1984 |
| 1278 | Donald & Danny Dews Production | | Oil Operator | Jan 2025 |
| 1279 | Donald J. Zadeck | | Oil & Gas Operator | Feb 1998 |
| 1280 | Donald Owens | | Oil & Gas Operator | Dec 2024 |
| 1281 | Donn G. Thompson, Et Al | | Oil Operator | Apr 1987 |
| 1282 | Donnie R. Morrow | | Oil Operator | Dec 2024 |
| 1283 | Donny Joe Barnhill | | Gas Operator | Dec 2024 |
| 1284 | Doran & Braddock & Nelson Petr | | Oil Operator | Feb 1982 |
| 1285 | Doran And Braddock | | Oil & Gas Operator | Nov 1984 |
| 1286 | Dorbert Oil & Gas, Inc. | | Gas Operator | Aug 1988 |
| 1287 | Dorcheat Oil & Gas, LLC | | Oil & Gas Operator | Dec 2024 |
| 1288 | Dorchester Exploration, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 2001 |
| 1289 | Dore-Dyn Production Co., Inc. | | Oil & Gas Operator | Jul 1993 |
| 1290 | Dorothy F. Hamlin | | Oil Operator | Dec 1985 |
| 1291 | Dorothy Oil Company | | Oil & Gas Operator | Oct 1994 |
| 1292 | Dossie Dews | | Oil & Gas Operator | Dec 2024 |
| 1293 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Dec 2025 |
| 1294 | Double J Operating Company, Inc. | San Antonio, TX 78205 | Oil Operator | Jan 2008 |
| 1295 | Douglas Edwards | | Oil Operator | Nov 1993 |
| 1296 | Dove Drilling, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 1997 |
| 1297 | Dow Chemical Co. | | Oil & Gas Operator | Dec 1997 |
| 1298 | Dow Intrastate Gas Company | | Oil Operator | Dec 2023 |
| 1299 | Dow Mineral & Royalty Co, Inc | | Oil & Gas Operator | Jun 1994 |
| 1300 | Doyle Dempsey | | Oil Operator | May 1997 |