| 1201 | Apex Crude Oil Co | Logan, OH 43138 | Oil & Gas Operator | Dec 1996 |
| 1202 | Apex DRLG | Bermuda Dunes, CA 92203 | Oil & Gas Operator | Dec 2019 |
| 1203 | Apex Energy (Pa) LLC | Wexford, PA 15090-7383 | Gas Operator | Mar 2025 |
| 1204 | Apex Energy, Inc. | Corpus Chrsti, TX 78413 | Oil & Gas Operator | May 2025 |
| 1205 | Apex Energy, L.L.C. | Tulsa, OK 74114 | Oil & Gas Operator | Jan 2025 |
| 1206 | Apex Minerals Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 1994 |
| 1207 | Apex Oil & Gas, Inc. | Houston, TX 77067 | Oil & Gas Operator | Oct 2009 |
| 1208 | Apex Oil Ventures Inc | | Oil & Gas Operator | Dec 2024 |
| 1209 | Apex Operating & Equip. Co. | Bowie, TX 76230 | Oil & Gas Operator | Nov 2003 |
| 1210 | Apex Operating Partners, LLC | San Angelo, TX 76902 | Oil & Gas Operator | May 2025 |
| 1211 | Apex Production LTD. | Albany, TX 76430 | Oil Operator | May 2025 |
| 1212 | Apex Resources Inc | Allison Park, PA 15101-3838 | Oil & Gas Operator | Dec 1993 |
| 1213 | Apex Resources LLC | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 1214 | Apex Royalties, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 1997 |
| 1215 | Apexco, Inc. | Sand Springs, OK 74063 | Oil & Gas Operator | Mar 2025 |
| 1216 | Apexco-McCormick-Coastal | | Oil & Gas Operator | Dec 1977 |
| 1217 | Apexway Corp. | | Oil Operator | Dec 2024 |
| 1218 | API Operating Co. | Houston, TX 77036 | Oil & Gas Operator | May 2025 |
| 1219 | Apogee Oil & Gas LLC | Edmond, OK 73034 | Oil Operator | Feb 2025 |
| 1220 | Apollo 17 Oil And Gas Inc | | Oil Operator | Feb 1988 |
| 1221 | Apollo Drilling And Exploration | | Oil & Gas Operator | Oct 1980 |
| 1222 | Apollo Energies | Pratt, KS 67124 | Oil Operator | Aug 2016 |
| 1223 | Apollo Energies Inc | Pratt, KS 67124 | Oil & Gas Operator | Jan 2025 |
| 1224 | Apollo Energy Operating Co, LP | Lake Charles, LA 70601 | Oil & Gas Operator | Dec 2024 |
| 1225 | Apollo Energy Operating, LP | | Oil & Gas Operator | Mar 2011 |
| 1226 | Apollo Energy, L.L.C. | | Oil & Gas Operator | Jul 2018 |
| 1227 | Apollo Energy, L.P. | Lake Charles, LA 70601 | Oil Operator | May 2014 |
| 1228 | Apollo Exploration And Development Inc | | Oil & Gas Operator | Nov 2024 |
| 1229 | Apollo Gas Co | Pittsburgh, PA 15236-1435 | Gas Operator | Dec 1991 |
| 1230 | Apollo Operating LLC | | Oil & Gas Operator | Sep 2013 |
| 1231 | Apollo Petroleum Corporation | | Oil & Gas Operator | Dec 2012 |
| 1232 | Apollo Resources LLC | Vintondale, PA 15961-0222 | Oil & Gas Operator | Mar 2025 |
| 1233 | App Energy, LLC | Monroe, MI 48161 | Oil & Gas Operator | Dec 2021 |
| 1234 | Appalachian Ener Tech Inc | Clearwater, FL 33518 | Oil & Gas Operator | Dec 2001 |
| 1235 | Appalachian Energy Inc | Pittsburgh, PA 15220 | Gas Operator | Dec 2008 |
| 1236 | Appalachian Expl Inc | Hartville, OH 44632-550-550 | Oil & Gas Operator | Dec 1992 |
| 1237 | Appalachian Exploration Corp | McMurray, PA 15317-3452 | Gas Operator | Dec 1995 |
| 1238 | Appalachian Petrol Corp | Girard, OH 44420 | Oil & Gas Operator | Dec 1989 |
| 1239 | Appalachian Resources Of Florida, LLC | Fort Myers, FL 33902 | Oil Operator | Dec 2023 |
| 1240 | Appaloosa Operating Company LLC | The Woodlands, TX 77387 | Oil & Gas Operator | Apr 2019 |
| 1241 | Apple Petroleum Corp | Mountainside, NJ 7092 | Oil Operator | Mar 2013 |
| 1242 | Appleton Oil Company | Chicago, IL 60657-4097 | Oil & Gas Operator | May 1993 |
| 1243 | Applied Mechanics Corp. | Bridgeport, WV 26330-4609 | Oil & Gas Operator | Dec 2021 |
| 1244 | Appling, J. B. | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 1245 | Approach Operating LLC | Fort Worth, TX 76116 | Oil & Gas Operator | Sep 2020 |
| 1246 | Apr Operating LLC | Midland, TX 79701 | Oil & Gas Operator | Jun 2022 |
| 1247 | April Rain Prod. Co., Inc. | | Oil & Gas Operator | Jul 1992 |
| 1248 | Apv Caddo Pine LLC | | Oil & Gas Operator | Dec 2024 |
| 1249 | Apv McCamey LLC | MC Camey, TX 79752 | Oil & Gas Operator | May 2025 |
| 1250 | Apx & Assoc. | FT Stockton, TX 79735 | Oil & Gas Operator | Sep 1998 |
| 1251 | Apx Corporation | Houston, TX 77251 | Oil & Gas Operator | Dec 2009 |
| 1252 | Apx Western Corporation | Denver, CO 80217 | Oil & Gas Operator | Sep 1991 |
| 1253 | Aqua-Oil Inc | Enid, OK 73703-6511 | Oil & Gas Operator | May 2019 |
| 1254 | Aquanyx Midstream LLC | Oklahoma City, OK 73131 | Oil Operator | Mar 2025 |
| 1255 | Aquarius Oil And Gas | Casper, WY 82601 | Oil & Gas Operator | Sep 2017 |
| 1256 | Aquila Energy Resources Corp. | Houston, TX 77042 | Oil & Gas Operator | Nov 2013 |
| 1257 | Aquila Resources | Burkesville, KY 42717 | Oil & Gas Operator | Dec 2022 |
| 1258 | Aquinas Oil & Gas, LLC | Muenster, TX 76252 | Oil Operator | May 2025 |
| 1259 | Arabella Operating, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 1260 | Arabella Petroleum Company, LLC | Austin, TX 78701 | Oil & Gas Operator | May 2025 |
| 1261 | Arabie, Inc. | Lake Charles, LA 70605 | Oil & Gas Operator | May 2025 |
| 1262 | Aracca Petroleum Company | | Oil Operator | May 1984 |
| 1263 | Aracca Petroleum Corporation | | Oil Operator | Dec 1987 |
| 1264 | Aralpa Corporation | | Oil & Gas Operator | May 1987 |
| 1265 | Araluen Energy, Inc. | Houston, TX 77094 | Oil Operator | Jun 2022 |
| 1266 | Aramco Petroleum LLC | Burkburnett, TX 76354 | Oil Operator | May 2025 |
| 1267 | Aran Energy USA Inc. | | Oil & Gas Operator | Apr 1997 |
| 1268 | Aransas DRLG & Workover Co Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Jul 2019 |
| 1269 | Aransas Oil Company, Inc. | San Antonio, TX 78253 | Oil & Gas Operator | Jan 1999 |
| 1270 | Aransas Resources, Inc | Houston, TX 77083 | Oil & Gas Operator | Dec 2005 |
| 1271 | Aransas Resources, LP | Houston, TX 77006 | Oil & Gas Operator | Oct 2006 |
| 1272 | Arapaho Oil & Gas Inc | Roswell, NM 88202 | Oil & Gas Operator | Nov 1994 |
| 1273 | Arapaho Petroleum Inc | Englewood, CO 80155 | Oil & Gas Operator | Nov 1998 |
| 1274 | Arapaho Ventures Of Ny | Englewood, CO 80155 | Oil & Gas Operator | Dec 1990 |
| 1275 | Arapahoe Prod. Co. | Borger, TX 79008 | Oil & Gas Operator | May 2012 |
| 1276 | Arapahoe Resources LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Feb 2025 |
| 1277 | Arapahoe SPV LLC | | Oil & Gas Operator | Feb 2023 |
| 1278 | Aratex Production Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2003 |
| 1279 | Araxas Exploration, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 1998 |
| 1280 | Arb Energy Utah, LLC | Katy, TX 77494 | Oil & Gas Operator | Jan 2025 |
| 1281 | Arbco, Inc. | | Oil & Gas Operator | Jan 1996 |
| 1282 | Arben Oil, Inc. | Coleman, TX 76834 | Oil & Gas Operator | May 2025 |
| 1283 | Arbol Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | May 2025 |
| 1284 | Arbor Operating LLC | | Oil & Gas Operator | Mar 2024 |
| 1285 | Arbor Petroleum Corporation | Oklahoma City, OK 73102-4003 | Oil & Gas Operator | Mar 2011 |
| 1286 | Arbor Petroleum Inc | | Oil Operator | Jan 2003 |
| 1287 | Arbor Resources LLC | | Oil & Gas Operator | Dec 2007 |
| 1288 | Arbuckle Energy Inc. | Wichita, KS 67202 | Oil & Gas Operator | Jul 2018 |
| 1289 | Arbuckle Enterprises, Inc. | Edmond, OK 73083 | Oil & Gas Operator | Feb 2025 |
| 1290 | Arbuckle Service | Iola, KS 66749 | Oil Operator | Feb 1993 |
| 1291 | Arbuckle, A. Dale | Grenola, KS 67346 | Oil Operator | Sep 1990 |
| 1292 | Arbuckle, A. Dale & Kathryn E. Rev Trust | Grenola, KS 67346 | Oil & Gas Operator | May 2024 |
| 1293 | Arcadia Energy Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2025 |
| 1294 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 1295 | Arcadia Oil Company | Edmond, OK 73013-9009 | Oil & Gas Operator | Oct 2015 |
| 1296 | Arcadia Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | May 2025 |
| 1297 | Arcadia Refining Company | Tyler, TX 75701 | Oil & Gas Operator | Jan 1994 |
| 1298 | Arcadian Mineral Development | Brownwood, TX 76801 | Oil & Gas Operator | Dec 2013 |
| 1299 | Arcadian Mineral Development,LLC | Brownwood, TX 76801 | Oil & Gas Operator | May 2025 |
| 1300 | Arcadian Resources LLC | Glen Elder, KS 67446 | Oil & Gas Operator | May 2025 |