| 1201 | Sierra Production Company | | Oil & Gas Operator | May 1986 |
| 1202 | Sierra Reserve Company | | Oil Operator | Dec 1985 |
| 1203 | Sierra Resources, Inc. | Oklahoma City, OK 73142 | Oil & Gas Operator | Sep 2024 |
| 1204 | Sierra Resources, LLC | Houston, TX 77219 | Oil & Gas Operator | Aug 2021 |
| 1205 | Sierra Trading Corporation | | Oil & Gas Operator | Sep 1978 |
| 1206 | Siete Oil And Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Aug 2003 |
| 1207 | Sigma Corporation | Charleston, WV 25301-0000 | Gas Operator | Dec 2021 |
| 1208 | Sigma Energy & Explor., Co LLC | Ozona, TX 76943 | Oil & Gas Operator | Feb 2010 |
| 1209 | Sigma Energy, LLC | | Oil Operator | Jul 2024 |
| 1210 | Sigma Oper & Develop Co., Inc. | Midland, TX 79701 | Oil & Gas Operator | Nov 2024 |
| 1211 | Sigmon Construction Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 2024 |
| 1212 | Sigmon Production Company, Inc. | Longview, TX 75608 | Oil & Gas Operator | Dec 2013 |
| 1213 | Signal Hill Company LLC | Cody, WY 82414 | Oil & Gas Operator | Sep 2024 |
| 1214 | Signal Hill Expl & Pet Inc | Duncan, OK 73533 | Oil & Gas Operator | Mar 2015 |
| 1215 | Signal Hill Petroleum Inc. | | Oil & Gas Operator | Sep 2024 |
| 1216 | Signal Oil And Gas Company | Colleyville, TX 76034 | Oil & Gas Operator | Nov 2024 |
| 1217 | Signal Oil Company, LLC | Kilgore, TX 75663 | Oil & Gas Operator | Nov 2024 |
| 1218 | Signal Petroleum | | Oil & Gas Operator | Jul 1980 |
| 1219 | Signal, LLC | | Oil & Gas Operator | Aug 2024 |
| 1220 | Signal, LLC Of Mississippi | | Oil & Gas Operator | Jun 2024 |
| 1221 | Signature Exploration Inc. | Shawnee, OK 74804-4130 | Oil & Gas Operator | Mar 2015 |
| 1222 | Sikes Oil Company Inc | Velma, OK 73091-0759 | Oil & Gas Operator | Jan 2014 |
| 1223 | Sikes Operating, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Jun 2003 |
| 1224 | Sikes, Arlas M. | Brownwood, TX 76801 | Oil & Gas Operator | May 2000 |
| 1225 | Silberman A & M Oil | Oklahoma City, OK 73122-3096 | Oil & Gas Operator | Apr 2014 |
| 1226 | Silent Stone Energy LLC | Barnsdal, OK 74002 | Oil & Gas Operator | Aug 2024 |
| 1227 | Silhan, Terry | Marion, KS 66861 | Oil & Gas Operator | Dec 2009 |
| 1228 | Sills Oil Co | Osage, OK 74054 | Oil Operator | May 2024 |
| 1229 | Siltstone Resources Op II, LLC | Wilmington, DE 19801 | Oil & Gas Operator | Nov 2024 |
| 1230 | Silvco Energy, LLC | | Oil Operator | Apr 2014 |
| 1231 | Silver Creek Oil | Merkel, TX 79536 | Oil & Gas Operator | Aug 2003 |
| 1232 | Silver Creek Oil & Gas, Inc. | Wichita, KS 67203 | Oil Operator | Dec 1997 |
| 1233 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Nov 2024 |
| 1234 | Silver Creek Permian Op Co, LLC | Irving, TX 75038 | Oil & Gas Operator | Apr 2023 |
| 1235 | Silver Creek Resources, LLC | Irving, TX 75038 | Oil & Gas Operator | Apr 2017 |
| 1236 | Silver Cross Energy Partners LLC | Richmond, TX 77469 | Oil & Gas Operator | Nov 2024 |
| 1237 | Silver Eagle Oil Company | Ada, OK 74820 | Oil Operator | Dec 2004 |
| 1238 | Silver Exploration Company | | Oil & Gas Operator | Sep 2024 |
| 1239 | Silver Fox Oil & Gas LLC | Hebbronville, TX 78361 | Oil & Gas Operator | Nov 2024 |
| 1240 | Silver Hill Energy Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Nov 2024 |
| 1241 | Silver Hill Energy Partners, LLC | Dallas, TX 75219 | Oil & Gas Operator | Feb 2017 |
| 1242 | Silver Mountain Energy LLC | | Gas Operator | Aug 2024 |
| 1243 | Silver Oak Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2016 |
| 1244 | Silver Oak Operating, Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 2009 |
| 1245 | Silver Oak Operating, LLC | Longview, TX 75604 | Oil & Gas Operator | Nov 2024 |
| 1246 | Silver Oil & Gas Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Nov 2024 |
| 1247 | Silver Petroleum Inc | | Gas Operator | Dec 2001 |
| 1248 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | Sep 2024 |
| 1249 | Silver Run Oil & Gas | | Oil & Gas Operator | Dec 2021 |
| 1250 | Silver Spike Energy Oper, LLC | Midland, TX 79710 | Oil & Gas Operator | Dec 2015 |
| 1251 | Silver Spike Energy Operating Of NM, LLC | Midland, TX 79701 | Oil Operator | Jul 2016 |
| 1252 | Silver Star Of Nevada Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Aug 2024 |
| 1253 | Silver Star Operating Co., LLC | Nada, TX 77460 | Gas Operator | Nov 2024 |
| 1254 | Silver Star Production Co | Moore, OK 73160-6202 | Oil & Gas Operator | Aug 2024 |
| 1255 | Silver Thread Oil & Gas, Inc. | | Oil & Gas Operator | Jul 2015 |
| 1256 | Silver Tusk Operating Co. LLC | Houston, TX 77056 | Oil & Gas Operator | Nov 2018 |
| 1257 | Silverado Oil Inc | Greeley, CO 80631 | Oil Operator | Apr 2000 |
| 1258 | Silverado Oil LTD | Ardmore, OK 73401 | Oil & Gas Operator | Jun 2003 |
| 1259 | Silverback Operating II, LLC | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 2024 |
| 1260 | Silverback Operating, LLC | San Antonio, TX 78257 | Oil & Gas Operator | Oct 2016 |
| 1261 | Silverbacq LLC | | Oil & Gas Operator | Sep 2024 |
| 1262 | Silverbow Resources Oper, LLC | Houston, TX 77024 | Oil & Gas Operator | Nov 2024 |
| 1263 | Silverbrook Operating II LLC | Barker, TX 77413 | Oil Operator | Nov 2024 |
| 1264 | Silverbrook Operating, LLC | Barker, TX 77413 | Oil & Gas Operator | Nov 2024 |
| 1265 | Silverridge Corp | Van Buren, AR 72956 | Oil & Gas Operator | Mar 2015 |
| 1266 | Silvertin Farm Production LLC | Tulsa, OK 74137 | Oil & Gas Operator | Apr 2020 |
| 1267 | Simar Petroleum, LLC | | Oil Operator | Jun 2024 |
| 1268 | Simasko Producti | | Oil Operator | Dec 1986 |
| 1269 | Simasko Production Co | Denver, CO 80204 | Oil & Gas Operator | Nov 1997 |
| 1270 | Simata Energy | Midland, TX 79708 | Oil & Gas Operator | Nov 2024 |
| 1271 | Simata Energy, LLC | Midland, TX 79708 | Oil & Gas Operator | Nov 2024 |
| 1272 | Simco Oil Company | | Oil Operator | Jul 1990 |
| 1273 | Simco Oil, LLC | Lytle, TX 78052 | Oil Operator | Nov 2024 |
| 1274 | Simco Operating | Shawnee, OK 74804-2501 | Oil Operator | Jan 2013 |
| 1275 | Simco Petroleum | Cheyenne, WY 82003 | Oil & Gas Operator | Oct 2009 |
| 1276 | Simcoe LLC | Durango, CO 81301 | Oil & Gas Operator | Sep 2024 |
| 1277 | Simcoe Oil Company | Scottsdale, AZ 85258-2553 | Oil & Gas Operator | May 2020 |
| 1278 | Simme, Steven | Elma, NY 14052 | Gas Operator | Dec 2023 |
| 1279 | Simminger, Robert John Jr | | Oil Operator | Jul 2024 |
| 1280 | Simmons Donald M | Muskogee, OK 74401 | Oil & Gas Operator | May 2013 |
| 1281 | Simmons Engr & Consulting Co | Farmington, NM 87499 | Gas Operator | Feb 2002 |
| 1282 | Simmons Evelyn B-Per Represent | Edmond, OK 73083-3610 | Oil & Gas Operator | Aug 1996 |
| 1283 | Simmons Mack McCoy | Cement, OK 73017 | Oil Operator | Jul 2024 |
| 1284 | Simmons Oil Corporation | | Oil Operator | Jan 1989 |
| 1285 | Simmons Robert Z | | Oil Operator | Dec 1990 |
| 1286 | Simmons, Inc.* D. J. | | Oil & Gas Operator | May 2020 |
| 1287 | Simmons, L.B. Energy, Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 2000 |
| 1288 | Simmons, Stanley J. | Olney, TX 76374 | Oil & Gas Operator | Aug 1994 |
| 1289 | Simon Joseph W | Carney, OK 74832-0443 | Oil & Gas Operator | Dec 2016 |
| 1290 | Simon Of Bolivar Enterprises Inc | Cuba, NY 14727 | Oil & Gas Operator | Dec 2023 |
| 1291 | Simon Oil Company | Ardmore, OK 73401-1045 | Oil Operator | Mar 2024 |
| 1292 | Simon Oil LLC | Kaycee, WY 82639 | Oil Operator | Jul 2024 |
| 1293 | Simon Royce & Joyce | Tecumseh, OK 74873-7341 | Oil Operator | Jun 2018 |
| 1294 | Simon, W. D. Oil Co. | Kermit, TX 79745 | Oil & Gas Operator | Nov 2024 |
| 1295 | Simple Operating LLC | Cross Plains, TX 76443 | Oil Operator | Nov 2024 |
| 1296 | Simpson B T Jr | Orlando, FL 32806 | Oil & Gas Operator | Dec 1986 |
| 1297 | Simpson Bros. Oil Co. | Odessa, TX 79760 | Oil & Gas Operator | Jan 2001 |
| 1298 | Simpson Bros. Oil Co.-Odessa | Odessa, TX 79760 | Oil & Gas Operator | Jan 2001 |
| 1299 | Simpson Gary H | Albion, PA 16401-8008 | Gas Operator | Dec 2014 |
| 1300 | Simpson Oil & Land Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2024 |