| 301 | North Central Casing Pullers,Inc | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 302 | O'Neill Properties, LTD. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 303 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 304 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 305 | Oil & Gas Properties | Midland, TX 79704 | Oil & Gas Operator | Jul 2025 |
| 306 | Oil Projects, LLC | Houston, TX 77027 | Oil & Gas Operator | Jul 2025 |
| 307 | Okie Operating Company, LTD. | Tulsa, OK 74103 | Oil & Gas Operator | Jul 2025 |
| 308 | Okla. Magic Circle Energy Corp. | Shawnee, OK 74801 | Oil & Gas Operator | Jul 2004 |
| 309 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 310 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Jul 2025 |
| 311 | On Pointe Operating LLC | Jones, OK 73049 | Oil & Gas Operator | Jul 2025 |
| 312 | Osborn Heirs Co | San Antonio, TX 78217 | Oil & Gas Operator | Jun 2025 |
| 313 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 314 | Ozark Exploration, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Jul 2025 |
| 315 | P1 Energy, LLC | Judson, TX 75660 | Oil & Gas Operator | Jul 2025 |
| 316 | Paint Rock Operating, LLC | San Angelo, TX 76904 | Oil & Gas Operator | Jul 2025 |
| 317 | Paragon Corporation | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 318 | Paragon Oil & Gas, LLC | Aledo, TX 76008 | Oil & Gas Operator | Jul 2025 |
| 319 | Parallel Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Jan 2010 |
| 320 | Parallel Petroleum LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 321 | Parker & Parsley Development Co. | Midland, TX 79702 | Oil & Gas Operator | May 1995 |
| 322 | Parker & Parsley Development L.P | Midland, TX 79702 | Oil & Gas Operator | Oct 2007 |
| 323 | Parsley Energy Operations, LLC | Irving, TX 75038 | Oil & Gas Operator | Jan 2021 |
| 324 | Partee Drilling Inc. | Big Spring, TX 79721 | Oil & Gas Operator | Jul 2025 |
| 325 | Pathfinder Exploration LLC | Norman, OK 73069-8516 | Gas Operator | Aug 2003 |
| 326 | Patno Oil & Gas Company | Zapata, TX 78076 | Oil & Gas Operator | Jul 2025 |
| 327 | Patriot Resources, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 328 | Patterson Petroleum LLC | Snyder, TX 79550 | Oil & Gas Operator | Oct 2007 |
| 329 | Patterson Petroleum, Inc. | Snyder, TX 79550 | Oil & Gas Operator | Feb 2000 |
| 330 | Patton, E. N. Oil Company, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 331 | Patton, Lloyd | Fort Worth, TX 76113 | Oil & Gas Operator | Aug 2003 |
| 332 | Patton, Lloyd J Estate | Fort Worth, TX 76113 | Oil & Gas Operator | Aug 2003 |
| 333 | Pecos Operators, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1993 |
| 334 | Pedco Resources Company | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2008 |
| 335 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 336 | Pennzoil Petroleum Company | Houston, TX 77252 | Oil & Gas Operator | Nov 1999 |
| 337 | Penroc Oil Corp. | Hobbs, NM 88241 | Oil & Gas Operator | May 2025 |
| 338 | Permian Resources Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 339 | Permian Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 340 | Petex | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2025 |
| 341 | Petra Oleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 342 | Petro-Smith Operating LLC | Houston, TX 77010 | Oil & Gas Operator | Jul 2025 |
| 343 | Petro-West Corporation | Lubbock, TX 79404 | Oil & Gas Operator | Oct 2001 |
| 344 | Petrodata Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 345 | Petroleum Technical Services Co. | Midland, TX 79707 | Oil & Gas Operator | Dec 2004 |
| 346 | Petx Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 347 | Pharaoh Oil & Gas, Inc. | MC Camey, TX 79752 | Oil & Gas Operator | Jul 2025 |
| 348 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 349 | Phillips, Ken | San Angelo, TX 76904 | Oil & Gas Operator | Jun 2021 |
| 350 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Dec 2024 |
| 351 | Pilgrim Energy Partners L.L.C. | Fairfield, IL 62837 | Oil Operator | Jul 2025 |
| 352 | Pioneer Exploration, LLC | Houston, TX 77090 | Oil & Gas Operator | May 2025 |
| 353 | Pioneer Exploration, LTD. | Houston, TX 77090 | Oil & Gas Operator | Sep 2008 |
| 354 | Pioneer Natural Res. USA, Inc. | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 355 | Pitco Investments, LTD. | Scottsdale, AZ 85261 | Oil & Gas Operator | Jan 2013 |
| 356 | Pittencrieff America Inc | Abilene, TX 79608 | Oil & Gas Operator | Feb 2003 |
| 357 | Plains Marketing, LP | Cushing, OK 74023 | Oil Operator | Jan 2012 |
| 358 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 359 | Pogo Producing Company LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 360 | Prime Operating Company | Houston, TX 77024 | Oil & Gas Operator | Jul 2025 |
| 361 | Prize Operating Company | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2016 |
| 362 | Probity Operating, LLC | Midland, TX 79708 | Oil & Gas Operator | Jul 2014 |
| 363 | Proex Energy Management, L.L.C. | Spring, TX 77386 | Oil & Gas Operator | Jul 2025 |
| 364 | Pure Resources, L.P. | Midland, TX 79701 | Oil & Gas Operator | Mar 2006 |
| 365 | Purvis Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Jul 2025 |
| 366 | Q Natural Resources, LLC | Jones, OK 73049 | Oil & Gas Operator | Jul 2025 |
| 367 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Apr 2025 |
| 368 | Questa Oil & Gas Co. | Tulsa, OK 74170 | Oil & Gas Operator | Mar 2015 |
| 369 | R K Petroleum Corp. | Midland, TX 79708 | Oil & Gas Operator | May 2024 |
| 370 | R. K. G. Engineering, Inc. | Odessa, TX 79760 | Oil & Gas Operator | Jul 2025 |
| 371 | Rafter T Resources LLC | Midland, TX 79705 | Oil & Gas Operator | Jul 2025 |
| 372 | Ram Operating Inc. | Browns, IL 62818 | Oil & Gas Operator | Aug 2008 |
| 373 | Ramtex Energy LLC | Tulsa, OK 74114 | Oil & Gas Operator | Jul 2025 |
| 374 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 375 | Rayden | Midland, TX 79711 | Oil & Gas Operator | Jul 2025 |
| 376 | Reatta Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 377 | Recovery Operating LP | San Angelo, TX 76904 | Oil & Gas Operator | Jul 2025 |
| 378 | Red Oak Energy Co | San Angelo, TX 76906 | Oil & Gas Operator | Jul 2025 |
| 379 | Regal Development Inc. | Eldorado, TX 76936 | Gas Operator | Jul 1996 |
| 380 | Regent Oil & Gas Company, L.P. | Dallas, TX 75225 | Oil & Gas Operator | Sep 2006 |
| 381 | Reliance Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 382 | Reliance Operating Company | Midland, TX 79702 | Oil & Gas Operator | Feb 2000 |
| 383 | Remnant Oil Operating, LLC | Midland, TX 79704 | Oil & Gas Operator | Jul 2024 |
| 384 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Jul 2025 |
| 385 | Rendova Oil Company, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2002 |
| 386 | Riata Energy Inc | Oklahoma City, OK 73101 | Oil & Gas Operator | Apr 2008 |
| 387 | Richey, Ray Management Co., Inc. | Fort Worth, TX 76108 | Oil & Gas Operator | Jul 2025 |
| 388 | Ricks Expl Acquisition Corp | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2004 |
| 389 | Ricks Expl Acquisition LLC | Midland, TX 79701 | Oil & Gas Operator | Aug 2013 |
| 390 | Ricks Exploration, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 391 | Ridgeline Energy Inc. | Miami, FL 33130 | Oil & Gas Operator | Jul 2025 |
| 392 | Ridgeline Resources, LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 393 | Rio Rocky Enterprises, Inc. | Eldorado, TX 76936 | Oil & Gas Operator | Jul 2025 |
| 394 | Rio-Tex, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2025 |
| 395 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 396 | Robertson Resources, Inc. | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Jul 2025 |
| 397 | Roca Resource Company, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 398 | Rodessa Management, Inc. | Longview, TX 75606 | Oil & Gas Operator | May 1995 |
| 399 | Roil Production Company | Houston, TX 77056 | Gas Operator | Sep 2005 |
| 400 | Rumble Energy LLC | Skiatook, OK 74070 | Oil & Gas Operator | Jul 2025 |