| 301 | Long Oil & Natural Gas Corp. | | Oil & Gas Operator | Feb 1996 |
| 302 | Long Oil And Gas Expl., LTD | | Oil & Gas Operator | Apr 1988 |
| 303 | Long Operating, L.L.C. | Shreveport, LA 71166 | Oil & Gas Operator | Jun 2006 |
| 304 | Louisiana Energy Consultants, Inc. | | Oil & Gas Operator | Dec 2024 |
| 305 | Louisiana General Petr. Corp. | | Oil & Gas Operator | Mar 1980 |
| 306 | Louisiana Intrastate Gas Corp. | | Oil Operator | Feb 1994 |
| 307 | Louisiana Operating Co., Inc. | | Oil & Gas Operator | Aug 1994 |
| 308 | Louisiana-Hunt Petroleum Corp. | | Oil & Gas Operator | Dec 1985 |
| 309 | Loutex Production Company | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 310 | Lyons Petroleum, Inc. | | Oil & Gas Operator | Oct 1988 |
| 311 | M & B Oil Company | Holliday, TX 76366 | Oil & Gas Operator | Apr 2025 |
| 312 | M2 Louisiana Gas Service, LLC | | Oil Operator | Apr 2010 |
| 313 | Magnum Gas Pipeline, L.L.C. | | Oil Operator | Dec 2024 |
| 314 | Mallard Drilling Corp. | | Oil & Gas Operator | Jan 1993 |
| 315 | Maple Gulf Coast Props. Corp. | | Oil & Gas Operator | Jun 1989 |
| 316 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | May 2025 |
| 317 | Marlan Anderson | | Oil Operator | Jan 2025 |
| 318 | Marlin Exploration, LLC | | Oil & Gas Operator | May 2025 |
| 319 | Maroski, Inc. | | Oil Operator | Jan 1989 |
| 320 | Marshall Exploration, Inc. | | Oil & Gas Operator | Jun 1992 |
| 321 | Martin Production Company | | Oil & Gas Operator | Dec 2024 |
| 322 | Martineau Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Jan 2025 |
| 323 | Matador Production Company | Dallas, TX 75240 | Oil & Gas Operator | Jul 2025 |
| 324 | Matthews Operating Co., Inc. | | Gas Operator | Aug 2001 |
| 325 | Maximus Operating, LTD. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 326 | May Petroleum, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Nov 1998 |
| 327 | McGoldrick Oil Company | Shreveport, LA 71129 | Oil & Gas Operator | Jul 2020 |
| 328 | McIlhenny-Powell Operating Co | | Gas Operator | Aug 1983 |
| 329 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 330 | Mettz,Carmody & Foster Oil Co | | Oil Operator | May 1990 |
| 331 | Mich-La Oil & Gas Exploration | | Oil & Gas Operator | Jan 1992 |
| 332 | Mid South Oil & Gas Expl Inc | | Oil & Gas Operator | Jan 1992 |
| 333 | Mid-Con Energy Operating, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | May 2020 |
| 334 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2025 |
| 335 | Mineral Development, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Aug 1996 |
| 336 | Mobley Valve Service, Inc. | | Oil & Gas Operator | Nov 2006 |
| 337 | Monroe Well Service-Petrovest | | Oil Operator | Dec 1988 |
| 338 | Mooringsport Energy Prod Corp | | Oil & Gas Operator | Oct 1994 |
| 339 | Moran Oil Co., Inc. | | Oil & Gas Operator | Aug 2009 |
| 340 | Moransco Energy Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 341 | MRD Operating LLC | | Oil & Gas Operator | Dec 2016 |
| 342 | N Central Casing Pullers, Inc. | | Oil & Gas Operator | May 1994 |
| 343 | Nabors Drilling Company, Inc. | | Oil & Gas Operator | Sep 1977 |
| 344 | Nabors-Johnson Prod Co., Inc. | | Oil & Gas Operator | Dec 2020 |
| 345 | Nadel & Gussman-Jetta Oper. Co. | | Oil & Gas Operator | Mar 2012 |
| 346 | Nelson Energy, Inc. | | Oil & Gas Operator | Nov 2024 |
| 347 | Noram Field Services Corp. | | Oil Operator | Apr 1999 |
| 348 | Northeast Resources | | Oil & Gas Operator | Jan 1992 |
| 349 | Now Development Co., Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2017 |
| 350 | Oak Valley Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2015 |
| 351 | Ok-La-Tex Production, Inc. | | Oil & Gas Operator | Jan 1982 |
| 352 | Oleum Operating Company, L.C. | Longview, TX 75606 | Oil & Gas Operator | Dec 2021 |
| 353 | Olympic Oil & Gas Co., Inc. | | Oil Operator | Apr 1991 |
| 354 | Oracle Oil, LLC | | Oil & Gas Operator | Jul 2013 |
| 355 | Oryx Energy Company | Dallas, TX 75221 | Oil & Gas Operator | May 2002 |
| 356 | Osr Oil & Gas Corp | Midland, TX 79710 | Oil & Gas Operator | Dec 2024 |
| 357 | Oxy Petroleum Inc | | Oil & Gas Operator | Jan 1986 |
| 358 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 359 | P & P Producing Inc | Midland, TX 79702 | Oil & Gas Operator | Feb 2015 |
| 360 | Pace Royalty Trust Fund, Inc. | Shreveport, LA 71135 | Oil & Gas Operator | Nov 2001 |
| 361 | Palmer Petroleum Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Jul 2025 |
| 362 | Paloma Natural Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 363 | Pan-Ok Production Company | | Oil & Gas Operator | Nov 2024 |
| 364 | Par Exploration Co | | Oil & Gas Operator | Oct 1986 |
| 365 | Par Minerals Corporation | Shreveport, LA 71101 | Oil & Gas Operator | Jul 2025 |
| 366 | Parker & Parsley Devpt L P | | Oil & Gas Operator | Oct 1997 |
| 367 | Patton Operating Co. | Kilgore, TX 75663 | Oil & Gas Operator | Nov 1997 |
| 368 | Pearl Resources Inc. | | Oil & Gas Operator | Jul 1990 |
| 369 | Pedernales Petroleum Operating, LLC | | Oil & Gas Operator | Dec 2024 |
| 370 | Pelican Producing Co. | | Gas Operator | Nov 1992 |
| 371 | Pelto Oil Co | Houston, TX 77002 | Oil & Gas Operator | Nov 1998 |
| 372 | Pennzenergy Explor & Prod LLC | | Oil & Gas Operator | Dec 1999 |
| 373 | Pennzoil Exploration & Production Co. | Carthage, TX 75633 | Oil & Gas Operator | Mar 2008 |
| 374 | Peoples Energy Prod.-TX, L.P. | Houston, TX 77002 | Oil & Gas Operator | Sep 2007 |
| 375 | Perkins Oil Properties | | Oil & Gas Operator | Nov 2024 |
| 376 | Perry Point, Inc. | | Oil Operator | Mar 2022 |
| 377 | Pesco | | Oil & Gas Operator | Oct 1984 |
| 378 | Petro-Chem Operating Company, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jul 2025 |
| 379 | Petro-Hunt, L.L.C. | Dallas, TX 75201 | Oil & Gas Operator | Jul 2025 |
| 380 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 381 | Petroleum Recovery & Expl Inc. | | Oil Operator | Oct 1984 |
| 382 | PG&E Resources Company | Houston, TX 77042 | Oil & Gas Operator | May 1995 |
| 383 | Phillips Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Mar 2013 |
| 384 | Phoenix Opr Co Inc-Petrovest | | Oil Operator | Dec 1992 |
| 385 | Pinnacle Operating Company, Inc. | Shreveport, LA 71135 | Oil & Gas Operator | Jul 2025 |
| 386 | Pintail Minerals Corp. | | Gas Operator | Jun 1992 |
| 387 | Pioneer Natural Resources USA Inc | Irving, TX 75039 | Oil & Gas Operator | Mar 2025 |
| 388 | Placid Oil Company | Houston, TX 77227 | Oil & Gas Operator | Mar 2008 |
| 389 | Premier Natural Resources II,LLC | Tulsa, OK 74105 | Oil & Gas Operator | Feb 2015 |
| 390 | Pritchard Engineering | | Oil & Gas Operator | Mar 1989 |
| 391 | Procell & Procell | | Oil & Gas Operator | Jan 2003 |
| 392 | Producers Gas Transmission Inc | | Oil Operator | Nov 2024 |
| 393 | Qep Energy Company | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 394 | Quality Petroleum, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Jan 2022 |
| 395 | Quantent Energy Partners Operating LLC | | Gas Operator | Dec 2024 |
| 396 | Quest Energies | | Oil & Gas Operator | Mar 1997 |
| 397 | Quest Energies Group,LTD. | Shreveport, LA 71106 | Oil & Gas Operator | Mar 1997 |
| 398 | Quest Energies, L.L.C. | | Oil & Gas Operator | Jan 2025 |
| 399 | Questar Expl. And Prod. Co. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jul 2011 |
| 400 | Quinoco Petroleum Inc | | Oil & Gas Operator | Dec 1990 |