| 301 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 302 | R. K. G. Engineering, Inc. | Odessa, TX 79760 | Oil & Gas Operator | Dec 2025 |
| 303 | R3 Operating Corporation | Denver, CO 80222 | Oil & Gas Operator | Dec 2025 |
| 304 | Raptor Petroleum II, LLC | Houston, TX 77251 | Oil & Gas Operator | Dec 2025 |
| 305 | Raw Oil & Gas, Inc. | Lubbock, TX 79401 | Oil & Gas Operator | Dec 2025 |
| 306 | Reagle Production Co. | Snyder, TX 79549 | Oil & Gas Operator | Apr 2004 |
| 307 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 308 | Redmon Oil Company, Inc., The | Plano, TX 75023 | Oil & Gas Operator | Dec 2025 |
| 309 | Redwood Operating, Inc. | Houston, TX 77058 | Oil & Gas Operator | Dec 2025 |
| 310 | Remnant Oil Operating, LLC | Midland, TX 79704 | Oil & Gas Operator | Jul 2024 |
| 311 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Dec 2025 |
| 312 | Renaud Oil Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 313 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 314 | Rising Star Energy, L.L.C. | Dallas, TX 75219 | Oil & Gas Operator | Aug 2006 |
| 315 | RJD Management Co., Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Dec 2025 |
| 316 | Robert C. Brower, LLC | Southlake, TX 76092 | Oil & Gas Operator | Dec 2025 |
| 317 | Robertson Resources, Inc. | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2025 |
| 318 | Rocker A Operating Company | Post, TX 79356 | Oil & Gas Operator | Aug 2022 |
| 319 | Roff Operating Company LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 320 | Rover Petroleum Operating, LLC | Fort Worth, TX 76101 | Oil & Gas Operator | Dec 2025 |
| 321 | Royal American Oil & Gas | Post, TX 79356 | Oil & Gas Operator | Jan 2019 |
| 322 | Royal Oil & Gas Corp. | Indiana, PA 15701 | Oil & Gas Operator | Apr 2014 |
| 323 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 324 | Saga Petroleum LLC Of Colorado | Norman, OK 73072 | Oil & Gas Operator | Dec 2025 |
| 325 | Saguaro Petroleum, LLC | Midland, TX 79705 | Oil & Gas Operator | Dec 2025 |
| 326 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 327 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Aug 2025 |
| 328 | Sayers Operating Company | Midland, TX 79705 | Oil & Gas Operator | Feb 2005 |
| 329 | Scout Energy Management LLC | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 330 | Scythian, LTD. | Midland, TX 79701 | Oil & Gas Operator | Dec 2020 |
| 331 | Seagull Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 332 | Seely Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 333 | Sharp Image Energy, Inc. | Big Spring, TX 79721 | Oil & Gas Operator | Dec 2025 |
| 334 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 335 | Shenandoah Petroleum Corporation | Midland, TX 79705 | Oil & Gas Operator | Dec 2025 |
| 336 | Shenandoah Resources LLC | Houston, TX 77086 | Oil & Gas Operator | Apr 2020 |
| 337 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Aug 2025 |
| 338 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 339 | Sierra Lima Oil & Gas, LLC | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 340 | Sinclair Exploration Company | Abilene, TX 79604 | Oil & Gas Operator | Nov 1998 |
| 341 | Sinclair Oil & Gas Company | Salt Lake Cty, UT 84130 | Oil & Gas Operator | Dec 2025 |
| 342 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Dec 2025 |
| 343 | Smith Energy Operating Company | Lubbock, TX 79423 | Oil & Gas Operator | Dec 2025 |
| 344 | Smith Pipe Of Abilene | Abilene, TX 79608 | Oil & Gas Operator | Dec 2025 |
| 345 | Sojourner Drilling Corporation | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 346 | Southwest Royalties, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 347 | Spi Operations LLC | Midland, TX 79710 | Oil & Gas Operator | Jan 2013 |
| 348 | SSC, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Dec 2025 |
| 349 | Staley Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Jan 2022 |
| 350 | Stanolind Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2021 |
| 351 | Starkey Oilfield Service, Inc. | Sweet Home, TX 77987 | Oil & Gas Operator | Aug 2004 |
| 352 | Stelzer Drilling Co. Inc. | Post, TX 79356 | Oil Operator | Dec 2025 |
| 353 | Stelzer, E.A. Oil Company | Post, TX 79356 | Oil & Gas Operator | Feb 2002 |
| 354 | Stelzer, J. C. | Post, TX 79356 | Oil & Gas Operator | Dec 1995 |
| 355 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2025 |
| 356 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Sep 2025 |
| 357 | Stevens & Tull, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jun 2000 |
| 358 | Strawn Energy Services, LLC | Lubbock, TX 79404 | Oil Operator | Dec 2025 |
| 359 | Success Oil Company, Inc. | Beverly Hills, CA 90211 | Oil & Gas Operator | Dec 2025 |
| 360 | Suncoast Investments Co., Inc. | Plano, TX 75074 | Oil & Gas Operator | Oct 2001 |
| 361 | Swanson, Tommy Oil Co. | Electra, TX 76360 | Oil & Gas Operator | Mar 2017 |
| 362 | T & T Oil Co. | San Antonio, TX 78205 | Oil & Gas Operator | Dec 2002 |
| 363 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2025 |
| 364 | Talley Resources, Inc. | Houma, LA 70360 | Oil & Gas Operator | Apr 1993 |
| 365 | Tamer Oil & Gas | Seminole, TX 79360 | Oil & Gas Operator | Dec 2025 |
| 366 | Teaco | Snyder, TX 79550 | Oil & Gas Operator | Jan 1998 |
| 367 | Telesis Operating Co. | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 2025 |
| 368 | Teon Management, LLC | Midland, TX 79704 | Oil & Gas Operator | Mar 2020 |
| 369 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 370 | Terrace Petroleum Corporation | Midland, TX 79701 | Oil & Gas Operator | Jul 2013 |
| 371 | Tessara Petroleum Resources, LLC | Houston, TX 77086 | Oil & Gas Operator | Apr 2020 |
| 372 | Texas Vanguard Oil Company | Austin, TX 78720 | Oil & Gas Operator | Jan 2014 |
| 373 | Texland Petroleum Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2003 |
| 374 | Texland Petroleum, L.P. | Fort Worth, TX 76107 | Oil & Gas Operator | Dec 2025 |
| 375 | Texland-Rector & Schumacher | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2000 |
| 376 | Texon Oil Company, Inc. | Midland, TX 79710 | Oil & Gas Operator | Apr 2023 |
| 377 | Texstar Operating Inc. | Lubbock, TX 79423 | Oil & Gas Operator | Dec 2025 |
| 378 | Thompson, J. Cleo | Dallas, TX 75201 | Oil & Gas Operator | May 2024 |
| 379 | Three R Oil Company | Post, TX 79356 | Oil & Gas Operator | Dec 2025 |
| 380 | Three Span Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 381 | Threeway Drilling Company | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 382 | Threshold Development Company | Fort Worth, TX 76109 | Oil & Gas Operator | Aug 2016 |
| 383 | Tipperary Oil & Gas Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2014 |
| 384 | Tiza Energy, Inc. | Austin, TX 78715 | Oil & Gas Operator | Dec 2025 |
| 385 | TLH Production LLC | Abilene, TX 79602 | Oil & Gas Operator | Dec 2025 |
| 386 | TMBR/Sharp Drilling, Inc. | Midland, TX 79703 | Oil & Gas Operator | Feb 2004 |
| 387 | Tong Petrotech Inc. | Houston, TX 77079 | Oil & Gas Operator | Dec 2025 |
| 388 | Tonto Petroleum Corporation | Post, TX 79356 | Oil & Gas Operator | Jan 2007 |
| 389 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 390 | Totalfinaelf E&P USA Inc | Houston, TX 77024 | Oil & Gas Operator | Jul 2007 |
| 391 | Trail Mountain, Inc. | Artesia, NM 88210 | Oil & Gas Operator | Jan 2016 |
| 392 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 393 | Trey Resources Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2025 |
| 394 | Trinidad Energy, LLC | Midland, TX 79708 | Oil & Gas Operator | Dec 2025 |
| 395 | Trio Consulting & Management,LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Dec 2025 |
| 396 | TS Oil, LLC | Fort Worth, TX 76114 | Oil & Gas Operator | Dec 2025 |
| 397 | Tuthill & Barbee | Amarillo, TX 79101 | Oil & Gas Operator | Nov 1994 |
| 398 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 399 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 400 | United Energy Corporation | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2025 |