| 301 | Lomax Operating Company, Inc. | Abilene, TX 79602 | Oil & Gas Operator | Jun 2011 |
| 302 | Loudon Exploration, Inc. | San Antonio, TX 78217 | Oil & Gas Operator | Mar 2008 |
| 303 | Lovelady, I. W. | Albuquerque, NM 87111 | Oil & Gas Operator | Jan 1996 |
| 304 | Lowrance & Ray Exploration, Inc. | Fort Worth, TX 76147 | Oil & Gas Operator | Sep 2003 |
| 305 | Lytle Creek Operating, Inc. | Abilene, TX 79606 | Oil & Gas Operator | Dec 2025 |
| 306 | M E Klein & Associates, Inc. | Norman, OK 73070 | Oil & Gas Operator | Jun 2025 |
| 307 | M. E. Operating & Services, Inc. | Fort Worth, TX 76104 | Oil & Gas Operator | Dec 2025 |
| 308 | Maguire Oil Company | Dallas, TX 75270 | Oil & Gas Operator | Mar 2015 |
| 309 | Mallon Oil Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2005 |
| 310 | Mandarin Oil & Gas Company | Austin, TX 78714 | Oil & Gas Operator | Dec 2025 |
| 311 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Oct 2025 |
| 312 | Markay Oil & Gas Company | Midland, TX 79701 | Oil & Gas Operator | Sep 1998 |
| 313 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 314 | Martin Oil Co. | Aspermont, TX 79502 | Oil & Gas Operator | Jul 2023 |
| 315 | Martin, Jimmy Inc | San Angelo, TX 76904 | Oil & Gas Operator | Dec 2025 |
| 316 | Matador Operating Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2003 |
| 317 | Mathis & Sons, Inc. | Rule, TX 79547 | Oil & Gas Operator | Dec 2025 |
| 318 | McClymond, LTD. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2009 |
| 319 | McCutchin, Jerry | Dallas, TX 75380 | Oil & Gas Operator | Mar 2008 |
| 320 | McFarland & Scobey, Inc. | El Paso, TX 79947 | Oil & Gas Operator | Dec 2025 |
| 321 | McMahon-Bullington Drilling Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 1996 |
| 322 | Medders Oil Company | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2025 |
| 323 | Melton Operating Co. | Friendswood, TX 77546 | Oil & Gas Operator | Jul 2005 |
| 324 | Menasco, J. | Wichita Falls, TX 76310 | Oil & Gas Operator | Dec 2019 |
| 325 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 326 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Dec 2025 |
| 327 | Mescalero Energy, Inc. | San Antonio, TX 78231 | Oil & Gas Operator | Aug 2003 |
| 328 | Mesquite Oil & Gas Production | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2025 |
| 329 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 330 | Mid-Tex Energy Inc. | Costa Mesa, CA 92626 | Oil & Gas Operator | Jan 1999 |
| 331 | Midland Oil And Gas, Inc. | Midland, TX 79705 | Oil & Gas Operator | Dec 2025 |
| 332 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 333 | Mineral Technologies, Inc. | Midland, TX 79704 | Oil & Gas Operator | Dec 2025 |
| 334 | MMG Oil Company | Buffalo Gap, TX 79508 | Oil & Gas Operator | Aug 2006 |
| 335 | Moore Investment Co. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 336 | Moriah Resources, Inc. | Midland, TX 79704 | Oil & Gas Operator | Mar 2008 |
| 337 | Morris, W. Dale Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | Dec 2025 |
| 338 | Mortimer Exploration Company | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2003 |
| 339 | Mr Oil Company | Monahans, TX 79756 | Oil & Gas Operator | Nov 2004 |
| 340 | Musselman, Owen & King Oper.,Inc | Houston, TX 77002 | Oil & Gas Operator | Feb 1998 |
| 341 | MWL Energy LLC | Hamlin, TX 79520 | Oil Operator | Dec 2025 |
| 342 | Naumann Oil & Gas, Inc. | Austin, TX 78716 | Oil & Gas Operator | Dec 2025 |
| 343 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 344 | NBX Energy, LLC | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 2025 |
| 345 | New Height Energy, LLC | Houston, TX 77063 | Oil & Gas Operator | Dec 2025 |
| 346 | Norman Oil Corporation | Abilene, TX 79608 | Oil & Gas Operator | Mar 2000 |
| 347 | North American Exploration Co. | Abilene, TX 79602 | Oil & Gas Operator | Apr 1998 |
| 348 | Northstar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 349 | Norwood, A. N., Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 1997 |
| 350 | Nosivad Oil, Inc. | Clyde, TX 79510 | Oil & Gas Operator | Dec 2025 |
| 351 | O'Neill Properties, LTD. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 352 | Oasis Operating, Inc. | Lubbock, TX 79404 | Oil & Gas Operator | Nov 2020 |
| 353 | Odessa Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 354 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Dec 2025 |
| 355 | Omar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2013 |
| 356 | Omni Petroleum Corporation | Austin, TX 78738 | Oil & Gas Operator | Dec 2025 |
| 357 | Pan Western Energy Corporation | Tulsa, OK 74114 | Oil & Gas Operator | Dec 2025 |
| 358 | Panadero Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Apr 2002 |
| 359 | Par Producing Company | Snyder, TX 79550 | Oil & Gas Operator | Jun 2017 |
| 360 | Paragon Oil & Gas, LLC | Aledo, TX 76008 | Oil & Gas Operator | Dec 2025 |
| 361 | Pardue, William M., III | Fort Worth, TX 76116 | Oil & Gas Operator | Dec 1996 |
| 362 | Patton Exploration, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 363 | Patton, E. N. Oil Company, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 364 | Ped Oil Corporation | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 365 | Peregrine Petroleum PRTNR, LTD. | Dallas, TX 75201 | Oil & Gas Operator | Dec 2025 |
| 366 | Permex Petroleum Corporation | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 367 | Permian Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 368 | Petex | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2025 |
| 369 | Petra Oleum Corp. | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 370 | Petrogulf Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2025 |
| 371 | Petroleum Technical Services Co. | Midland, TX 79707 | Oil & Gas Operator | Dec 2004 |
| 372 | Petrotex, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Aug 2003 |
| 373 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 374 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 375 | Pickens Company, Inc., The | Dallas, TX 75225 | Oil & Gas Operator | Jan 2025 |
| 376 | Pinon Petroleum, Inc. | San Angelo, TX 76903 | Oil & Gas Operator | Apr 2004 |
| 377 | Pioneer Energy Corporation | Dallas, TX 75204 | Oil & Gas Operator | Dec 2025 |
| 378 | Pioneer Exploration Company | Houston, TX 77090 | Oil & Gas Operator | Oct 2025 |
| 379 | Pitcock, Inc. | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 380 | Plantation Operating, LLC | Houston, TX 77041 | Oil & Gas Operator | Nov 2011 |
| 381 | PNG Operating Company | Oklahoma City, OK 73172 | Oil & Gas Operator | Dec 2025 |
| 382 | Pogo Producing Company | Houston, TX 77002 | Oil & Gas Operator | Jan 2008 |
| 383 | Polaris Production Corp. | Midland, TX 79702 | Oil & Gas Operator | Jan 2024 |
| 384 | Polk Petroleum, Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2024 |
| 385 | Pop Operating Company | Denton, TX 76202 | Oil & Gas Operator | Dec 2025 |
| 386 | PPC Operating Company LLC | Houston, TX 77279 | Oil & Gas Operator | Jul 2019 |
| 387 | Presley Prod Investments, LLC | Abilene, TX 79604 | Oil Operator | Dec 2025 |
| 388 | Price, W. H. & Sons | Granbury, TX 76048 | Oil & Gas Operator | Nov 1997 |
| 389 | Pride Energy Company | Tulsa, OK 74170 | Oil & Gas Operator | Dec 2025 |
| 390 | Production Operators Of TX, LLC | Abilene, TX 79605 | Oil & Gas Operator | Dec 2025 |
| 391 | Pruitt Engineering & Petro. Co. | Kerrville, TX 78028 | Oil & Gas Operator | Jul 2007 |
| 392 | Pryor Petroleum Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2025 |
| 393 | Quail Well Service, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2025 |
| 394 | Quantum Investments | Lubbock, TX 79424 | Oil Operator | Dec 2025 |
| 395 | Quantum Resources Management LLC | Houston, TX 77010 | Oil & Gas Operator | Oct 2025 |
| 396 | Quatro Oil And Gas, Inc. | Joshua, TX 76058 | Oil & Gas Operator | Dec 2025 |
| 397 | Quest Petroleum, Inc. | Abilene, TX 79603 | Oil & Gas Operator | Dec 2025 |
| 398 | R & P Operating | Tuscola, TX 79562 | Oil & Gas Operator | Jun 1997 |
| 399 | R3 Operating Corporation | Denver, CO 80222 | Oil & Gas Operator | Dec 2025 |
| 400 | Railroad Commission Of Texas | Austin, TX 78701 | Oil Operator | Dec 2004 |