| 301 | L.C.S. Production Company | Abilene, TX 79608 | Oil & Gas Operator | Mar 2025 |
| 302 | Ladd Oil & Gas Corporation | Midland, TX 79711 | Oil & Gas Operator | Dec 2021 |
| 303 | Lanexco, Inc. | Sealy, TX 77474 | Oil & Gas Operator | Mar 2025 |
| 304 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Mar 2025 |
| 305 | Last Mile Production, LLC | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 306 | Lavanco Energy, Inc. | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2006 |
| 307 | Lavanco Energy, LTD. | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2024 |
| 308 | Lawrence, C. F. & Assoc. Inc. | Lubbock, TX 79401 | Oil & Gas Operator | Mar 2025 |
| 309 | LDF Energy, LLC | Midland, TX 79707 | Oil & Gas Operator | Mar 2025 |
| 310 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Mar 2025 |
| 311 | Limark Corporation | Midland, TX 79702 | Oil & Gas Operator | Dec 2003 |
| 312 | Lime Rock Resources A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 313 | Linn Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2019 |
| 314 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 315 | Lion Production, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2006 |
| 316 | Littlepage, Tommy | Graham, TX 76450 | Oil & Gas Operator | May 1996 |
| 317 | Live Oak Gas Company | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 318 | Lizard Lick Transport, LLC | Grandfalls, TX 79742 | Oil & Gas Operator | Mar 2025 |
| 319 | Llano Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 320 | Lonesome B, LLC | Monahans, TX 79756 | Oil & Gas Operator | Mar 2025 |
| 321 | Lre Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Nov 2016 |
| 322 | Lyn-San Company | Midland, TX 79708 | Oil & Gas Operator | Dec 2018 |
| 323 | Lynx Oil Co., Inc. | Denton, TX 76207 | Oil & Gas Operator | Sep 2003 |
| 324 | M-W-D Oil Co. | Odessa, TX 79760 | Oil & Gas Operator | Jul 1999 |
| 325 | M2 Squared Operating, LLC | Ranger, TX 76470 | Oil Operator | Mar 2025 |
| 326 | Mammoth Exploration LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2023 |
| 327 | Manning, Jack | Odessa, TX 79760 | Oil & Gas Operator | Dec 2003 |
| 328 | Maralo, Inc. | Midland, TX 79702 | Oil & Gas Operator | Dec 1998 |
| 329 | Marathon Oil Company | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 330 | Marcum Drilling Co. | Midland, TX 79701 | Oil & Gas Operator | Aug 2002 |
| 331 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Mar 2025 |
| 332 | Martin Foree Operating II, LLC | Royse City, TX 75189 | Oil & Gas Operator | Mar 2025 |
| 333 | Martin Foree Operating, LLC | Royse City, TX 75189 | Oil & Gas Operator | Mar 2025 |
| 334 | Martin, Jimmy Inc | San Angelo, TX 76904 | Oil & Gas Operator | Mar 2025 |
| 335 | Mas Operating Co. | Midland, TX 79710 | Oil & Gas Operator | Mar 2025 |
| 336 | Maynard Oil Co. | Denver, CO 80202 | Oil & Gas Operator | Sep 2004 |
| 337 | Mayne & Mertz, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2013 |
| 338 | McCabe Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 2009 |
| 339 | McClure Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 340 | McCutchin, Jerry | Dallas, TX 75380 | Oil & Gas Operator | Mar 2008 |
| 341 | McDaniel Company, Inc., The | Dallas, TX 75230 | Oil & Gas Operator | Mar 2025 |
| 342 | McDonnold Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 343 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 344 | Mei Operating Company | Lafayette, LA 70598 | Oil & Gas Operator | Aug 1997 |
| 345 | Memorial Production Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2025 |
| 346 | Mercury Operating, LLC | Dallas, TX 75208 | Oil & Gas Operator | Mar 2025 |
| 347 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 348 | Meridian Oil Inc.-Midland | Midland, TX 79702 | Oil & Gas Operator | Jul 1996 |
| 349 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | Mar 2025 |
| 350 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 351 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 352 | Midenergy Operating, LLC | Houston, TX 77024 | Oil & Gas Operator | Mar 2025 |
| 353 | Midland Oil And Gas, Inc. | Midland, TX 79705 | Oil & Gas Operator | Mar 2025 |
| 354 | Mike Oil LLC | Colorado City, TX 79512 | Oil Operator | Mar 2025 |
| 355 | Millwee Oil, Inc. | Midland, TX 79705 | Oil & Gas Operator | Mar 2025 |
| 356 | Millwee, John F. | Midland, TX 79705 | Oil & Gas Operator | Jul 2018 |
| 357 | Miltex Oil Company | Boerne, TX 78006 | Oil & Gas Operator | Mar 2025 |
| 358 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 359 | Mito Resources TX LLC | Edmond, OK 73013 | Oil & Gas Operator | Mar 2025 |
| 360 | MLC Operating, LP | Houston, TX 77063 | Oil & Gas Operator | Mar 2025 |
| 361 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 362 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 363 | Mogul Resources, LLC | Ranger, TX 76470 | Oil & Gas Operator | Mar 2025 |
| 364 | Momentum Energy Corporation | Austin, TX 78746 | Oil & Gas Operator | Mar 2025 |
| 365 | Momentum Energy, LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2004 |
| 366 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 367 | Moonlite Oil & Gas Company | Imperial, TX 79743 | Oil & Gas Operator | Mar 2025 |
| 368 | Mosaic Midland LLC | Dallas, TX 75367 | Oil Operator | Mar 2025 |
| 369 | Mr Oil Company | Monahans, TX 79756 | Oil & Gas Operator | Nov 2004 |
| 370 | MSSK Consulting LLC | San Antonio, TX 78253 | Oil Operator | Mar 2025 |
| 371 | Mulloy Operating, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 372 | Munn, W. H. Operating Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2002 |
| 373 | Muras Energy Inc | Edmond, OK 73013 | Oil & Gas Operator | Dec 2024 |
| 374 | Murphy Exploration & Prod. Co. | Houston, TX 77094 | Oil & Gas Operator | Jun 2011 |
| 375 | Murphy Oil USA Inc | New Orleans, LA 70161 | Oil & Gas Operator | Jan 1993 |
| 376 | MV2 Energy, Inc. | Houston, TX 77069 | Oil & Gas Operator | Mar 2025 |
| 377 | MWJ Producing Company | Midland, TX 79701 | Oil & Gas Operator | Jul 1998 |
| 378 | N & B Oil And Gas LLC | Monahans, TX 79756 | Oil & Gas Operator | Mar 2025 |
| 379 | N & O Oil Co. | Imperial, TX 79743 | Oil & Gas Operator | Mar 2025 |
| 380 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 381 | Nearburg Producing Company | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 382 | Nec Operating, LLC | Southlake, TX 76092 | Oil & Gas Operator | Mar 2025 |
| 383 | New Height Energy, LLC | Houston, TX 77063 | Oil & Gas Operator | Mar 2025 |
| 384 | Newfield Expl. Mid-Con. Inc | Tulsa, OK 74172 | Oil & Gas Operator | Jan 2015 |
| 385 | Newman Cubed, Inc. | Fort Worth, TX 76147 | Oil & Gas Operator | Mar 2025 |
| 386 | Newton Corp.,The | Dallas, TX 75251 | Oil & Gas Operator | Mar 2025 |
| 387 | Nitro Oil & Gas, LLC | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 388 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 389 | North Operating Company | Canton, TX 75103 | Oil & Gas Operator | Mar 2025 |
| 390 | Northstar Operating Company | Midland, TX 79702 | Oil & Gas Operator | Jun 2024 |
| 391 | Norwood, A. N., Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 1997 |
| 392 | O & O Operators, LLC. | Fate, TX 75132 | Oil & Gas Operator | Mar 2025 |
| 393 | O'Neill Properties, LTD. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 394 | O. H. B. Inc. | San Angelo, TX 76902 | Oil & Gas Operator | Sep 2019 |
| 395 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 396 | Occidental Permian LTD. | Houston, TX 77046 | Oil & Gas Operator | Mar 2025 |
| 397 | Ocean Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 398 | Odessa Exploration, Inc. | Midland, TX 79702 | Oil & Gas Operator | Mar 2025 |
| 399 | Oil Management Corporation | Dallas, TX 75206 | Oil & Gas Operator | Apr 2022 |
| 400 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Mar 2025 |