| 301 | O'Ryan Oil And Gas | Odessa, TX 79768 | Oil & Gas Operator | Apr 2024 |
| 302 | Occidental Energy Company, Inc. | Houston, TX 77282 | Oil & Gas Operator | Jul 2021 |
| 303 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 304 | Occidental Permian LTD. | Houston, TX 77046 | Oil & Gas Operator | Apr 2024 |
| 305 | Odom, R. H. | Snyder, TX 79550 | Oil & Gas Operator | Jun 1996 |
| 306 | Oilex Int'L Investments, Inc. | Luling, TX 78648 | Oil & Gas Operator | Apr 2024 |
| 307 | Oklahoma Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Aug 2013 |
| 308 | Omni Operating Company(A) | Dallas, TX 75370 | Oil & Gas Operator | Apr 2024 |
| 309 | Onaroll Operating LLC | Levelland, TX 79336 | Oil Operator | Apr 2024 |
| 310 | Orland Oil & Gas LLC | FT Lauderdale, FL 33305 | Oil Operator | Apr 2024 |
| 311 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 312 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Apr 2024 |
| 313 | Oxy USA WTP LP | Houston, TX 77046 | Oil & Gas Operator | Apr 2024 |
| 314 | P. L. O. | Boerne, TX 78006 | Oil & Gas Operator | Jun 2016 |
| 315 | Palisades Operating Company | Midland, TX 79702 | Oil & Gas Operator | Apr 2024 |
| 316 | Par Producing Company | Snyder, TX 79550 | Oil & Gas Operator | Jun 2017 |
| 317 | Parallel Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Jan 2010 |
| 318 | Parallel Petroleum LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2024 |
| 319 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 320 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 321 | Partee Drilling Inc. | Big Spring, TX 79721 | Oil & Gas Operator | Apr 2024 |
| 322 | Patrick Pet. Corp. Of Michigan | Houston, TX 77227 | Oil & Gas Operator | Aug 1995 |
| 323 | Patriot Resources, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 324 | Patterson Petroleum LLC | Snyder, TX 79550 | Oil & Gas Operator | Oct 2007 |
| 325 | Patterson Petroleum LP | Snyder, TX 79550 | Oil & Gas Operator | Mar 2008 |
| 326 | Patterson Petroleum, Inc. | Snyder, TX 79550 | Oil & Gas Operator | Feb 2000 |
| 327 | Pecanderosa Petroleum, Inc. | MC Queeney, TX 78123 | Oil Operator | Feb 2023 |
| 328 | Pennzenergy Exp. & Prod., L.L.C. | Houston, TX 77210 | Oil & Gas Operator | Mar 2000 |
| 329 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 330 | Pennzoil Petroleum Company | Houston, TX 77252 | Oil & Gas Operator | Nov 1999 |
| 331 | Peregrine Petroleum PRTNR, LTD. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 332 | Permian Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 333 | Perry Producing Company, Inc. | Ackerly, TX 79713 | Oil & Gas Operator | Apr 2024 |
| 334 | Petex | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2024 |
| 335 | Petrohawk Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2005 |
| 336 | Petroplex Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2024 |
| 337 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 338 | Pgi Operating, LLC | Sweetwater, TX 79556 | Oil Operator | Apr 2024 |
| 339 | Phillips 66 Company | Bartlesville, OK 74004 | Oil & Gas Operator | Aug 1997 |
| 340 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 341 | Philmar | Lubbock, TX 79403 | Oil Operator | Apr 2024 |
| 342 | Pioneer Exploration Company | Houston, TX 77090 | Oil & Gas Operator | Feb 2024 |
| 343 | Pioneer Exploration, LLC | Houston, TX 77090 | Oil & Gas Operator | Jan 2024 |
| 344 | Pioneer Exploration, LTD. | Houston, TX 77090 | Oil & Gas Operator | Sep 2008 |
| 345 | Pioneer Natural Res. USA, Inc. | Irving, TX 75038 | Oil & Gas Operator | Apr 2024 |
| 346 | Pitts Energy Co. | Midland, TX 79707 | Oil & Gas Operator | Apr 2024 |
| 347 | Plains Marketing LP | Cushing, OK 74023 | Oil & Gas Operator | Dec 2022 |
| 348 | Plantation Operating, LLC | Houston, TX 77041 | Oil & Gas Operator | Nov 2011 |
| 349 | Platinum Exploration Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |
| 350 | PMB Energy, Inc. | Snyder, TX 79549 | Oil & Gas Operator | Apr 2024 |
| 351 | Prensorus Energy, LLC | Abilene, TX 79604 | Oil & Gas Operator | Apr 2024 |
| 352 | Prentice Petroleum, Inc. | Abilene, TX 79605 | Oil & Gas Operator | Sep 1994 |
| 353 | Presco | Snyder, TX 79549 | Oil & Gas Operator | Apr 2024 |
| 354 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2024 |
| 355 | Primrose Operating Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2007 |
| 356 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 357 | Probe Exploration Company | Abilene, TX 79605 | Oil & Gas Operator | Apr 2024 |
| 358 | Pure Resources, L.P. | Midland, TX 79701 | Oil & Gas Operator | Mar 2006 |
| 359 | Purvis, J. H. | Midland, TX 79702 | Oil & Gas Operator | Dec 1994 |
| 360 | Quatro Oil And Gas, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Apr 2024 |
| 361 | Quien Sabe Operating, LLC | Sundown, TX 79372 | Oil & Gas Operator | Nov 2023 |
| 362 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | Apr 2024 |
| 363 | Rad Oil Company | Snyder, TX 79549 | Oil & Gas Operator | Apr 2024 |
| 364 | Radius Operating, LLC | Round Rock, TX 78664 | Oil & Gas Operator | Apr 2024 |
| 365 | Rainey, Wayne | Sweetwater, TX 79556 | Oil & Gas Operator | Feb 2019 |
| 366 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 367 | Raptor Petroleum II, LLC | Houston, TX 77251 | Oil & Gas Operator | Apr 2024 |
| 368 | Rasmussen, Hal J. Operating, Inc | Midland, TX 79701 | Oil & Gas Operator | Apr 2009 |
| 369 | Raw Oil & Gas, Inc. | Lubbock, TX 79401 | Oil & Gas Operator | Apr 2024 |
| 370 | RBJ & Associates, LP | Midland, TX 79707 | Oil Operator | Jan 2020 |
| 371 | Read & Stevens, Inc. | Denver, CO 80202 | Oil & Gas Operator | Jul 2023 |
| 372 | Red Sand Resources LLC | Midland, TX 79702 | Oil Operator | Dec 2023 |
| 373 | Red Star Operating LLC | Lubbock, TX 79403 | Oil Operator | Apr 2024 |
| 374 | Red Tank Resources, LLC | Dallas, TX 75379 | Oil & Gas Operator | Apr 2024 |
| 375 | Redwood Operating, Inc. | Houston, TX 77058 | Oil & Gas Operator | Apr 2024 |
| 376 | Regent Oil & Gas Company, L.P. | Dallas, TX 75225 | Oil & Gas Operator | Sep 2006 |
| 377 | Rendova Oil Company, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2002 |
| 378 | Rhombus Operating Co., LTD | Littleton, CO 80160 | Oil & Gas Operator | Apr 2024 |
| 379 | Richardson, Bud II | Graham, TX 76450 | Oil & Gas Operator | Apr 2024 |
| 380 | Rife Oil Properties Inc | Fort Worth, TX 76107 | Oil & Gas Operator | Apr 2024 |
| 381 | RJD Management Co., Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Apr 2024 |
| 382 | RK Oil Production | Post, TX 79356 | Oil & Gas Operator | Jun 2023 |
| 383 | Robert C. Brower, LLC | Southlake, TX 76092 | Oil & Gas Operator | Apr 2024 |
| 384 | Robertson Resources, Inc. | Midland, TX 79708 | Oil & Gas Operator | Apr 2024 |
| 385 | Robertson, French M. Oil Co. | Abilene, TX 79608 | Oil & Gas Operator | Mar 1995 |
| 386 | Rocker A Operating Company | Post, TX 79356 | Oil & Gas Operator | Aug 2022 |
| 387 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2024 |
| 388 | Round Rock Resources, Inc. | College Sta, TX 77845 | Oil & Gas Operator | Sep 2012 |
| 389 | Rover Petroleum Operating, LLC | Plano, TX 75075 | Oil & Gas Operator | Apr 2024 |
| 390 | Royalty Land & Dev. Co., Inc. | Wolfforth, TX 79382 | Oil & Gas Operator | Apr 2024 |
| 391 | Rozzlle Operating Company, LLC | Blackwell, TX 79506 | Oil & Gas Operator | Apr 2024 |
| 392 | Rudman Partnership, The | Dallas, TX 75201 | Oil & Gas Operator | Dec 2014 |
| 393 | Rusk Co. Well Service Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2024 |
| 394 | Russell, C. M. Oil Company | Lubbock, TX 79423 | Oil & Gas Operator | Jan 2008 |
| 395 | Russell, L. J. Oil Company | Snyder, TX 79549 | Oil & Gas Operator | Apr 2024 |
| 396 | Russell, Phillip | Colorado City, TX 79512 | Oil & Gas Operator | Apr 2024 |
| 397 | Ruwco Oil And Gas Corp. | Austin, TX 78701 | Oil & Gas Operator | Aug 2021 |
| 398 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 399 | S & M Royalty | Andrews, TX 79714 | Oil & Gas Operator | Jan 1997 |
| 400 | Saber Oil & Gas Ventures, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2024 |