| 301 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 302 | Petroreal Inc. | Temple, TX 76503 | Oil & Gas Operator | Apr 2024 |
| 303 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 304 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 305 | Pi Energy, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 2024 |
| 306 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Feb 2024 |
| 307 | Pintex Operating Inc. | Corpus Chrsti, TX 78478 | Oil & Gas Operator | Feb 2005 |
| 308 | Pioneer Natural Res. USA, Inc. | Irving, TX 75038 | Oil & Gas Operator | Apr 2024 |
| 309 | Pioneer Resources Producing, L.P | Irving, TX 75039 | Oil & Gas Operator | Feb 2001 |
| 310 | Plains Exploration & Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Jul 2013 |
| 311 | Plains Production Inc | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 1995 |
| 312 | Platinum Oil & Gas, L.L.C. | San Juan, TX 78589 | Oil & Gas Operator | Apr 2024 |
| 313 | Pmo | Garland, TX 75040 | Oil & Gas Operator | Feb 2018 |
| 314 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 315 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2024 |
| 316 | Premium Exploration Company | Early, TX 76803 | Oil & Gas Operator | Apr 2024 |
| 317 | Pringle Resources, Inc. | Houston, TX 77019 | Oil & Gas Operator | Apr 2024 |
| 318 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 319 | Proline Energy Resources Inc | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2024 |
| 320 | Questar Expl. And Prod. Co. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jul 2011 |
| 321 | Quisto Energy Corp. | Kerrville, TX 78029 | Oil & Gas Operator | Jan 1998 |
| 322 | Quisto Expl. & Production, L.C. | Sugar Land, TX 77478 | Oil & Gas Operator | Aug 1998 |
| 323 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 324 | Regent Oil & Gas Company, L.P. | Dallas, TX 75225 | Oil & Gas Operator | Sep 2006 |
| 325 | Remora Operating, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 326 | Republic Resources, LLC. | San Antonio, TX 78212 | Oil & Gas Operator | Apr 2024 |
| 327 | Ress Production Co. | Farmington, NM 87499 | Oil & Gas Operator | Apr 2024 |
| 328 | Reveille Resources | Houston, TX 77084 | Oil & Gas Operator | Apr 2011 |
| 329 | Reveille Resources (Texas), Inc. | Houston, TX 77084 | Oil & Gas Operator | Jan 2013 |
| 330 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 331 | Ricochet Energy, Inc. | San Antonio, TX 78258 | Oil & Gas Operator | Apr 2024 |
| 332 | Riddle Engineering Corp. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Jul 2011 |
| 333 | Rincon Petroleum Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 334 | Rio Bravo Oil Company | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2002 |
| 335 | Riseden Services, Inc. | Houston, TX 77256 | Oil & Gas Operator | Sep 1997 |
| 336 | RMS Monte Christo, LLC | Snowmass VLG., CO 81615 | Oil & Gas Operator | Mar 2023 |
| 337 | Rockdale Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Dec 2020 |
| 338 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Apr 2024 |
| 339 | Royal Production Company, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 340 | S.O.C. Investors, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2024 |
| 341 | Safari Production Company, Inc. | McAllen, TX 78501 | Oil & Gas Operator | Apr 2024 |
| 342 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 343 | Samson Exploration LLC | Tulsa, OK 74101 | Oil & Gas Operator | Feb 2024 |
| 344 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 345 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2024 |
| 346 | Sanchez Oil & Gas Corporation | Houston, TX 77056 | Oil & Gas Operator | Apr 2024 |
| 347 | Sanchez-O'Brien Oil & Gas Corp | Houston, TX 77057 | Oil & Gas Operator | May 1998 |
| 348 | Sandia Energy Corporation-NM | Holdenville, OK 74848 | Oil & Gas Operator | Aug 2003 |
| 349 | Saxum Oil & Gas, LLC | Beeville, TX 78104 | Oil & Gas Operator | Apr 2024 |
| 350 | Scorpion Operating, Inc. | Benavides, TX 78341 | Oil Operator | Apr 2024 |
| 351 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 352 | Seneca Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 353 | Shell Trading Us Company | Houston, TX 77210 | Oil & Gas Operator | Jan 2024 |
| 354 | Shell Western E&P | Houston, TX 77001 | Oil & Gas Operator | Apr 2024 |
| 355 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 356 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Jan 2024 |
| 357 | Sierra Resources, LLC | Houston, TX 77219 | Oil & Gas Operator | Aug 2021 |
| 358 | Smith Oil Company | Smackover, AR 71762 | Oil Operator | Mar 2024 |
| 359 | Smith Production Inc. | The Woodlands, TX 77381 | Oil & Gas Operator | Apr 2024 |
| 360 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 361 | Sonora Petroleum Corp. | Austin, TX 78734 | Oil & Gas Operator | Apr 2024 |
| 362 | South Central Texas Oil & Gas Co | Houston, TX 77060 | Oil & Gas Operator | Apr 2024 |
| 363 | South Leeville, LLC | Houston, TX 77069 | Oil & Gas Operator | Oct 2022 |
| 364 | South Texas Limited Partnership | Houston, TX 77060 | Oil & Gas Operator | Feb 1994 |
| 365 | South Texas Operating Company | San Antonio, TX 78217 | Oil & Gas Operator | Apr 2024 |
| 366 | Southern G Holdings, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2007 |
| 367 | Southern Tejas Asset Group LLC | McAllen, TX 78501 | Oil & Gas Operator | Apr 2024 |
| 368 | Southwest Oil & Land, Inc. | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Dec 1999 |
| 369 | Sparta Exploration LLC | Houston, TX 77279 | Oil & Gas Operator | Apr 2024 |
| 370 | Spiller Operating Co., Inc. | Round Rock, TX 78665 | Oil & Gas Operator | May 2015 |
| 371 | Spiller, Robert S. | San Antonio, TX 78213 | Oil & Gas Operator | Oct 1995 |
| 372 | Spindletop Oil & Gas Co. | Dallas, TX 75230 | Oil & Gas Operator | Apr 2024 |
| 373 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Apr 2024 |
| 374 | St. Mary Energy Company | Houston, TX 77079 | Oil & Gas Operator | Aug 2008 |
| 375 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 376 | Stampede Energy Corp. | Canada, 00100 | Oil & Gas Operator | Mar 2000 |
| 377 | Star Of Texas Energy SRVS, Inc. | Austin, TX 78702 | Oil & Gas Operator | Apr 2024 |
| 378 | Starco Exploration, Inc. | Dallas, TX 75360 | Oil & Gas Operator | Apr 2024 |
| 379 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2024 |
| 380 | Strata Operating, Inc. | Corpus Chrsti, TX 78466 | Oil & Gas Operator | Apr 2024 |
| 381 | Sue-Ann Operating, L.C. | Victoria, TX 77903 | Oil & Gas Operator | Apr 2024 |
| 382 | Sue-Ann Production Company | Victoria, TX 77903 | Oil & Gas Operator | Mar 2008 |
| 383 | Suemaur Expl. & Prod., LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 384 | Suemaur Exploration, Inc. | Corpus Chrsti, TX 78470 | Oil & Gas Operator | Mar 2008 |
| 385 | Sure Flow Oil & Gas Company | Victoria, TX 77902 | Oil & Gas Operator | Mar 2008 |
| 386 | Sure Flow Oil & Gas, Inc. | Victoria, TX 77902 | Oil & Gas Operator | Apr 2024 |
| 387 | Synergy Oil & Gas, Inc. (A) | Houston, TX 77024 | Oil & Gas Operator | Aug 2001 |
| 388 | Synergy Oil & Gas, L.P. | Houston, TX 77024 | Oil & Gas Operator | May 2012 |
| 389 | Synergy Production Company | Houston, TX 77024 | Oil & Gas Operator | Jan 1996 |
| 390 | Tana Oil And Gas Corporation | Irving, TX 75062 | Oil & Gas Operator | Mar 2000 |
| 391 | Teal Energy USA, Inc. | Houston, TX 77057 | Oil & Gas Operator | Apr 2024 |
| 392 | Tecpetrol Operating LLC | Houston, TX 77027 | Oil & Gas Operator | Dec 2015 |
| 393 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 394 | Tesoro E&P Company, L.P. | San Antonio, TX 78216 | Oil & Gas Operator | Jan 2000 |
| 395 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Apr 2024 |
| 396 | Texakoma E & P, LLC | Plano, TX 75024 | Oil & Gas Operator | Apr 2024 |
| 397 | Texas Fuel Company | Galveston, TX 77550 | Oil & Gas Operator | Apr 2024 |
| 398 | Texas Independent Explor LTD. | Houston, TX 77024 | Oil & Gas Operator | Apr 2024 |
| 399 | Texas Independent Explor., Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2002 |
| 400 | Texas Western Energy Corporation | Portland, TX 78374 | Oil & Gas Operator | Nov 2002 |