| 301 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 302 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 303 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2025 |
| 304 | San Marco Petroleum Inc | Denver, CO 80293 | Oil & Gas Operator | Oct 2025 |
| 305 | Sandlot Oil & Gas LLC | Gruver, TX 79040 | Oil & Gas Operator | Dec 2025 |
| 306 | Sanguine Gas Exploration, LLC | Tulsa, OK 74119 | Oil & Gas Operator | Dec 2025 |
| 307 | Santa Fe Energy Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 308 | Santa Fe Snyder Corporation | Houston, TX 77024 | Oil & Gas Operator | Oct 2000 |
| 309 | Sbog, LLC | Granbury, TX 76048 | Oil & Gas Operator | Feb 2021 |
| 310 | Scout Energy Management LLC | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 311 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 312 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 313 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 314 | SLT Dakota Operating, Inc. | Yukon, OK 73099 | Oil & Gas Operator | Dec 2025 |
| 315 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 316 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 317 | St Johns Operating #1 LP | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 318 | Stallion Energy, Inc. | Houston, TX 77060 | Oil & Gas Operator | Oct 2017 |
| 319 | Statex Petroleum Inc | Dallas, TX 75229 | Oil & Gas Operator | Dec 2000 |
| 320 | Sting Exploration Company | Tulsa, OK 74120 | Oil Operator | Sep 2004 |
| 321 | Strat Land Exploration Company | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2025 |
| 322 | Summit Resources MGMT., LLC. | Edmond, OK 73083 | Oil & Gas Operator | Dec 2025 |
| 323 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 324 | Suoco Oil Corporation | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 325 | Taylor Energy Corporation | Amarillo, TX 79114 | Oil & Gas Operator | Feb 1999 |
| 326 | TC Oil And Gas, LLC | Denton, TX 76205 | Oil Operator | Dec 2025 |
| 327 | Tecolote Energy Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | Jan 2024 |
| 328 | Templar Operating LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Aug 2025 |
| 329 | Texaco E & P Inc. | Houston, TX 77099 | Oil & Gas Operator | Dec 2025 |
| 330 | Texakoma E & P, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2025 |
| 331 | Texakoma Operating, L.P. | Plano, TX 75024 | Oil & Gas Operator | Mar 2025 |
| 332 | Tide West Oil Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2021 |
| 333 | Trans Terra Corp., International | Amarillo, TX 79159 | Oil & Gas Operator | Feb 2009 |
| 334 | Triple T Resources, LP | Dallas, TX 75205 | Oil & Gas Operator | Jun 2025 |
| 335 | Tyler Oil & Gas Inc. | Tyler, TX 75702 | Oil & Gas Operator | Sep 2004 |
| 336 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 337 | Unbridled Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 338 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 339 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 340 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Dec 2025 |
| 341 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 342 | Upland Resources, Inc. | Canadian, TX 79014 | Oil & Gas Operator | Dec 2009 |
| 343 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Dec 2025 |
| 344 | Valpoint Operating, LLC | Amarillo, TX 79101 | Oil & Gas Operator | Dec 2025 |
| 345 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Aug 2025 |
| 346 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Dec 2025 |
| 347 | Weinkauf Petroleum, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2025 |
| 348 | Wheeler Energy Co. | Tulsa, OK 74101 | Oil & Gas Operator | Aug 2025 |
| 349 | White Rock Oil & Gas, LLC | Plano, TX 75024 | Oil & Gas Operator | Dec 2025 |
| 350 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 351 | Whiting Petroleum Corporation | Denver, CO 80290 | Oil & Gas Operator | Jan 2025 |
| 352 | Whitmar Exploration Company | Denver, CO 80202 | Oil & Gas Operator | Aug 2025 |
| 353 | Wilbanks Exploration Inc | Denver, CO 80202 | Oil & Gas Operator | May 2002 |
| 354 | Wildhorse Operating Company | Ardmore, OK 73402 | Oil & Gas Operator | Dec 2025 |
| 355 | Will Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Aug 2025 |
| 356 | Winright Resources Operating,LLC | Houston, TX 77007 | Oil & Gas Operator | Dec 2025 |
| 357 | Wo Operating Company | Tulsa, OK 74159 | Oil & Gas Operator | Dec 2025 |
| 358 | Wynn-Crosby Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 359 | Wynn-Crosby Operating, LTD. | Dallas, TX 75201 | Oil & Gas Operator | Dec 2025 |
| 360 | Yale Oil Association | Oklahoma City, OK 73105 | Gas Operator | Oct 2013 |