| 301 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 302 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 303 | Patno Oil & Gas Company | Zapata, TX 78076 | Oil & Gas Operator | Oct 2025 |
| 304 | Patterson Petroleum, Inc. | Snyder, TX 79550 | Oil & Gas Operator | Feb 2000 |
| 305 | Patton, E. N. Oil Company, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 306 | Patton, Lloyd | Fort Worth, TX 76113 | Oil & Gas Operator | Aug 2003 |
| 307 | Patton, Lloyd J Estate | Fort Worth, TX 76113 | Oil & Gas Operator | Aug 2003 |
| 308 | PDC Energy | Denver, CO 80203 | Oil & Gas Operator | Nov 2012 |
| 309 | PDC-WV-Co Corporation | Denver, CO 80203 | Oil & Gas Operator | Aug 2010 |
| 310 | Pearl, Bill H. Productions, Inc. | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Oct 2025 |
| 311 | Pecos Operating Company, LLC | Midland, TX 79701 | Oil & Gas Operator | Jun 2021 |
| 312 | Pecos Operators, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1993 |
| 313 | Pedco Resources Company | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2008 |
| 314 | Penwell Energy, Inc. | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 315 | Perimeter Resource Company | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 316 | Perkins-Prothro Company | Wichita Falls, TX 76308 | Oil & Gas Operator | May 2002 |
| 317 | Petro Plex Oil Co Inc. | Homosassa, FL 34448 | Oil & Gas Operator | Jul 2020 |
| 318 | Petro-Smith Operating LLC | Houston, TX 77010 | Oil & Gas Operator | Oct 2025 |
| 319 | Petrodata Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 320 | Petx Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 321 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 322 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Jan 2025 |
| 323 | Pioneer Exploration Company | Houston, TX 77090 | Oil & Gas Operator | Jul 2025 |
| 324 | Pioneer Exploration, LLC | Houston, TX 77090 | Oil & Gas Operator | Aug 2025 |
| 325 | Pioneer Exploration, LTD. | Houston, TX 77090 | Oil & Gas Operator | Sep 2008 |
| 326 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 327 | Pittencrieff America, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Feb 2003 |
| 328 | Pitts Energy Co. | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 329 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 330 | Plains Marketing, LP | Cushing, OK 74023 | Oil Operator | Jan 2012 |
| 331 | Plateau Energy, LLC | Smyer, TX 79367 | Oil & Gas Operator | Dec 2023 |
| 332 | Plover Production Company | Fort Worth, TX 76109 | Oil & Gas Operator | Jul 2006 |
| 333 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 334 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 335 | Polk Petroleum, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2024 |
| 336 | Prestonwood Operating LLC | Addison, TX 75001 | Oil Operator | Oct 2025 |
| 337 | Prestonwood WF LLC | Addison, TX 75001 | Oil Operator | Oct 2025 |
| 338 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 339 | Probe Oil Company | Midland, TX 79710 | Oil & Gas Operator | Jul 2016 |
| 340 | Proven Reserves Management, Inc. | Dallas, TX 75370 | Oil & Gas Operator | Jun 2025 |
| 341 | Pure Resources, L.P. | Midland, TX 79701 | Oil & Gas Operator | Mar 2006 |
| 342 | Purvis Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 343 | Purvis, J. H. | Midland, TX 79702 | Oil & Gas Operator | Dec 1994 |
| 344 | Pyramid Energy Inc | San Antonio, TX 78216 | Oil & Gas Operator | Feb 2012 |
| 345 | Questa Oil & Gas Co. | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2015 |
| 346 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 347 | Radius Operating, LLC | Round Rock, TX 78664 | Oil & Gas Operator | Oct 2025 |
| 348 | Radtke, D.E. & Associates, Inc. | Midland, TX 79710 | Oil & Gas Operator | May 2004 |
| 349 | Randa Operating, Inc. | Big Lake, TX 76932 | Oil Operator | Oct 2025 |
| 350 | Ranger Operating Co. | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 351 | Ratex Energy Inc. | Manchaca, TX 78652 | Oil & Gas Operator | Sep 2002 |
| 352 | Rayden | Midland, TX 79711 | Oil & Gas Operator | Oct 2025 |
| 353 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 354 | Redbud E & P, Inc. | Giddings, TX 78942 | Oil & Gas Operator | Oct 2025 |
| 355 | Reichmann Petroleum Corp. | Grapevine, TX 76051 | Oil & Gas Operator | Oct 2025 |
| 356 | Remnant Oil Operating, LLC | Midland, TX 79704 | Oil & Gas Operator | Jul 2024 |
| 357 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Oct 2025 |
| 358 | Reo Operating LLC | Austin, TX 78747 | Oil & Gas Operator | Oct 2025 |
| 359 | Resaca Resources, L.L.C. | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 360 | Reserve Management, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Oct 2025 |
| 361 | Rex Energy Operating Corp. | State College, PA 16801 | Oil & Gas Operator | Jun 2012 |
| 362 | RHB Exploration & Production,LLC | Grapevine, TX 76099 | Oil & Gas Operator | Oct 2025 |
| 363 | Riata Energy Inc | Oklahoma City, OK 73101 | Oil & Gas Operator | Apr 2008 |
| 364 | Richman Petroleum Corp. | Grapevine, TX 76051 | Oil & Gas Operator | Jul 2006 |
| 365 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 366 | Riley Production | Throckmorton, TX 76483 | Oil & Gas Operator | Oct 2025 |
| 367 | Rio Exploration Company | San Antonio, TX 78209 | Gas Operator | Dec 2005 |
| 368 | Rio Grande Drilling Company | San Antonio, TX 78212 | Oil & Gas Operator | Dec 1999 |
| 369 | Rio-Tex, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2025 |
| 370 | Rivercity Operating, Inc. | Austin, TX 78766 | Oil & Gas Operator | Oct 2025 |
| 371 | RMC Petroleum, Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 1996 |
| 372 | Robert C. Brower, LLC | Southlake, TX 76092 | Oil & Gas Operator | Oct 2025 |
| 373 | Roca Production, Inc. | Fort Worth, TX 76107 | Oil & Gas Operator | Oct 2025 |
| 374 | Rockwood Resources Inc | Coleman, TX 76834 | Oil & Gas Operator | Oct 2025 |
| 375 | Rover Petroleum Operating, LLC | Fort Worth, TX 76101 | Oil & Gas Operator | Oct 2025 |
| 376 | Rowland, Rex D. | Midland, TX 79701 | Oil & Gas Operator | Dec 2017 |
| 377 | S & M Drilling, LLC | Wichita Falls, TX 76308 | Oil Operator | Sep 2023 |
| 378 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 379 | San Angelo Cetco, Inc. | San Angelo, TX 76901 | Oil & Gas Operator | Mar 1998 |
| 380 | Sandstone Operating Company, Inc | Odessa, TX 79762 | Oil & Gas Operator | Jul 1995 |
| 381 | Santa Fe Energy Oper. Part., LP | Houston, TX 77057 | Oil & Gas Operator | Dec 1994 |
| 382 | Santa Fe Energy Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 383 | Schkade & Bullock | San Angelo, TX 76901 | Oil & Gas Operator | Aug 2003 |
| 384 | Schkade Exploration | San Angelo, TX 76901 | Oil & Gas Operator | Oct 2025 |
| 385 | Scope Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 2003 |
| 386 | Scythian, LTD. | Midland, TX 79701 | Oil & Gas Operator | Dec 2020 |
| 387 | SDG Resources L.P. | Montrose, CO 81402 | Oil & Gas Operator | May 2006 |
| 388 | Seven Wells Oil & Gas Expl. | Abilene, TX 79601 | Oil & Gas Operator | Jun 2014 |
| 389 | Sha-Jam Operating Corp. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 390 | Sharp Image Energy, Inc. | Big Spring, TX 79721 | Oil & Gas Operator | Oct 2025 |
| 391 | Siana Oil & Gas | Conroe, TX 77305 | Oil & Gas Operator | Oct 2025 |
| 392 | Silver Oil & Gas Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Oct 2025 |
| 393 | Sinclair Exploration Company | Abilene, TX 79604 | Oil & Gas Operator | Nov 1998 |
| 394 | Sixess Energy, LLC | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 395 | SMC Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 396 | Smith Pipe Of Abilene | Abilene, TX 79608 | Oil & Gas Operator | Oct 2025 |
| 397 | Sojourner Drilling Corporation | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 398 | Sonoran Energy Inc. | Addison, TX 75001 | Oil & Gas Operator | Oct 2025 |
| 399 | Southern Union Exploration Co. | Austin, TX 78701 | Oil & Gas Operator | Feb 2002 |
| 400 | Southwest Petroleum | San Antonio, TX 78253 | Oil & Gas Operator | Oct 2025 |