| 301 | J.R. Oil And Gas Inc. | Alvin, TX 77511 | Oil & Gas Operator | May 2025 |
| 302 | J.W. Service Company | Smithville, TX 78957 | Oil & Gas Operator | May 2025 |
| 303 | Jalapeno Corporation | Albuquerque, NM 87103 | Oil & Gas Operator | Dec 2023 |
| 304 | Janssen, Wayne Allen | Runge, TX 78151 | Oil & Gas Operator | May 2010 |
| 305 | Jaybird Resources, LLC | Cuero, TX 77954 | Oil Operator | May 2025 |
| 306 | Jenex Petroleum Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | May 2025 |
| 307 | Jin Petroleum LLC | New Braunfels, TX 78130 | Oil Operator | May 2025 |
| 308 | Jones, L. E. Operating, Inc. | Duncan, OK 73534 | Oil & Gas Operator | May 2025 |
| 309 | JTB Oil Company, Inc. | Refugio, TX 78377 | Oil & Gas Operator | May 2025 |
| 310 | K.M.A. Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 311 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 312 | Kaler Energy Corp. | Boerne, TX 78006 | Oil & Gas Operator | May 2025 |
| 313 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 314 | Kebo Oil & Gas, Inc. | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 315 | Ken Petroleum Corporation | Dallas, TX 75206 | Oil & Gas Operator | Feb 2019 |
| 316 | Kenne Exploration, Inc. | Missouri City, TX 77489 | Oil & Gas Operator | May 2025 |
| 317 | Kerns O & G, Inc. | San Antonio, TX 78232 | Oil & Gas Operator | Dec 2004 |
| 318 | Kinder Morgan Production Co LLC | Midland, TX 79705 | Oil & Gas Operator | May 2025 |
| 319 | Kinder Morgan Production Co LP | Midland, TX 79701 | Oil & Gas Operator | Jul 2007 |
| 320 | Kling, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Dec 2000 |
| 321 | Klotzman, M. S. Exploration Co. | Victoria, TX 77903 | Oil & Gas Operator | May 2025 |
| 322 | KP Exploration, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1997 |
| 323 | KWS Oil & Gas, LLC | El Campo, TX 77437 | Oil & Gas Operator | May 2025 |
| 324 | Lacy, F. B. Inc. | Houston, TX 77055 | Oil & Gas Operator | Sep 1997 |
| 325 | Lagarto Company, The | Fredericksbrg, TX 78624 | Oil & Gas Operator | Apr 1995 |
| 326 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | May 2025 |
| 327 | Lewis Petro Properties, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | May 2025 |
| 328 | Lime Rock Resources A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Feb 2025 |
| 329 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 330 | Lindenmuth & Associates, Etex | Austin, TX 78703 | Oil & Gas Operator | Jun 2002 |
| 331 | Linder Oil Company,A Partnership | Shreveport, LA 71136 | Oil & Gas Operator | May 2025 |
| 332 | Little, Lou Operating Co., Inc. | Portland, TX 78374 | Oil & Gas Operator | Sep 2014 |
| 333 | LMP Exploration Operating, LLC | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Feb 2008 |
| 334 | LMP Petroleum, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Jan 2010 |
| 335 | Loin Energy Corporation | La Grange, TX 78945 | Oil & Gas Operator | May 2025 |
| 336 | Lone Oak Energy Inc | Kyle, TX 78640 | Oil & Gas Operator | May 2025 |
| 337 | Lonestar Operating, LLC | Houston, TX 77084 | Oil & Gas Operator | Nov 2022 |
| 338 | Long Trusts, The | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 339 | Lre Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Nov 2016 |
| 340 | Lucas Energy, Inc. | Houston, TX 77067 | Oil & Gas Operator | Feb 2017 |
| 341 | Lucky Lad Energy, LLC | Magnolia, TX 77353 | Oil & Gas Operator | May 2025 |
| 342 | Lytle Creek Operating, Inc. | Abilene, TX 79606 | Oil & Gas Operator | May 2025 |
| 343 | M. J. G., Inc. | Alice, TX 78333 | Oil & Gas Operator | Jul 2010 |
| 344 | Magic Circle Energy | Oklahoma City, OK 73185 | Oil & Gas Operator | Dec 1983 |
| 345 | Magnolia Oil & Gas Operating LLC | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 346 | Magnum Engineering Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 347 | Magnum Operating, LLC | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 348 | Magnum Producing & Operating Co. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jan 2004 |
| 349 | Magnum Producing, LP | Corpus Chrsti, TX 78401 | Oil & Gas Operator | May 2025 |
| 350 | Maguire Oil Company | Dallas, TX 75270 | Oil & Gas Operator | Mar 2015 |
| 351 | Maralo, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1998 |
| 352 | Marathon Oil Ef LLC | Houston, TX 77252 | Oil & Gas Operator | May 2025 |
| 353 | Marmaton Oil Company | Houston, TX 77002 | Oil & Gas Operator | Jul 1998 |
| 354 | Marquee Corporation | Houston, TX 77024 | Oil & Gas Operator | May 2025 |
| 355 | Marwell Petroleum LTD Partnrship | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 356 | Marwell Petroleum, Inc. | Houston, TX 77057 | Oil & Gas Operator | Apr 2006 |
| 357 | Mascot Oil Company | Schulenburg, TX 78956 | Oil & Gas Operator | May 2025 |
| 358 | Mastodon Operating Company, LLC | Houston, TX 77027 | Oil & Gas Operator | May 2025 |
| 359 | Matador Production Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 360 | McCarter, A. Nelson | Houston, TX 77063 | Oil & Gas Operator | Aug 2003 |
| 361 | McFarland Energy, Inc. | New Orleans, LA 70160 | Oil & Gas Operator | Dec 2009 |
| 362 | McRae Exploration & Prod., Inc. | Houston, TX 77064 | Oil & Gas Operator | Feb 2017 |
| 363 | Mego Resources, LLC | Taft, TX 78390 | Oil & Gas Operator | May 2025 |
| 364 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 365 | Meridian Oil Production Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 2024 |
| 366 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 367 | Messy Oil And Gas, LLC | Garwood, TX 77442 | Oil & Gas Operator | May 2025 |
| 368 | Mestena Operating, LTD. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jun 2009 |
| 369 | Midpar L.P. | Midland, TX 79702 | Oil & Gas Operator | Feb 1995 |
| 370 | Midstates Corporation | San Antonio, TX 78217 | Oil & Gas Operator | May 2025 |
| 371 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |
| 372 | Miner, R. C. Inc. | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Apr 2002 |
| 373 | Miner, R. C. Oil, Inc. | MC Queeney, TX 78123 | Oil & Gas Operator | May 2025 |
| 374 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 375 | Mission River Systems, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | May 2025 |
| 376 | Modern Exploration, Inc. | Sherman, TX 75090 | Oil & Gas Operator | May 2025 |
| 377 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 378 | Moose Oil & Gas Co. | Houston, TX 77002 | Oil & Gas Operator | Feb 2000 |
| 379 | Moose Operating Co., Inc. | Houston, TX 77006 | Oil & Gas Operator | May 2025 |
| 380 | Mosaic Oil LLC | Dallas, TX 75205 | Oil & Gas Operator | May 2025 |
| 381 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 382 | Mosley Oil &Gas Inc | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 383 | Mueller Engineering Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Feb 2002 |
| 384 | Mueller Exploration, Inc. | Portland, TX 78374 | Oil & Gas Operator | May 2025 |
| 385 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2025 |
| 386 | Nance Engineering Inc. | Houston, TX 77058 | Oil & Gas Operator | Mar 2002 |
| 387 | Nei Production, Inc. | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 388 | Nelmark Energy Corporation | San Antonio, TX 78231 | Oil & Gas Operator | Apr 2002 |
| 389 | Nelson, James L. | Pettus, TX 78146 | Oil & Gas Operator | May 2025 |
| 390 | Ness Operating Of Texas, Inc. | Weatherford, TX 76087 | Oil & Gas Operator | Dec 2004 |
| 391 | Neumin Production Company | Point Comfort, TX 77978 | Oil & Gas Operator | May 2025 |
| 392 | New Century Exploration, Inc. | Spring, TX 77379 | Oil & Gas Operator | May 2025 |
| 393 | NFR Energy, LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2017 |
| 394 | Nog Production & Operating LLC | Goliad, TX 77963 | Oil & Gas Operator | May 2025 |
| 395 | North American Royalties, Inc. | Chattanooga, TN 37408 | Oil & Gas Operator | Oct 2001 |
| 396 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 397 | Null, W.M. Operations, Inc. | Corpus Chrsti, TX 78475 | Oil & Gas Operator | Jun 2002 |
| 398 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 399 | Okie Crude Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 400 | Okie Operating Company, LTD. | Tulsa, OK 74103 | Oil & Gas Operator | May 2025 |