| 301 | Kelsey Operating, Inc. | Houston, TX 77077 | Oil Operator | Feb 2022 |
| 302 | Kennemer, Darrell | Boyd, TX 76023 | Oil Operator | Mar 2025 |
| 303 | Kimleco Petroleum, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2025 |
| 304 | Kincaid Etal, Inc. | Holliday, TX 76366 | Oil Operator | Mar 2025 |
| 305 | Kincaid, Joey | Holliday, TX 76366 | Oil & Gas Operator | Mar 2005 |
| 306 | King & West | Wichita Falls, TX 76307 | Oil & Gas Operator | May 1994 |
| 307 | Kodiak Operating, L.L.C. | Olney, TX 76374 | Oil & Gas Operator | Mar 2025 |
| 308 | Kodiak Petroleum Corp. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 1996 |
| 309 | Koonce Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Oct 1993 |
| 310 | Kramer, Clifford A. | Wichita Falls, TX 76301 | Oil & Gas Operator | Sep 1997 |
| 311 | Kroh Operating LLC | Fort Worth, TX 76114 | Oil & Gas Operator | Mar 2025 |
| 312 | Krot Oil Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 313 | KTC Oil Enterprises, LLC | Dallas, TX 75247 | Oil & Gas Operator | Mar 2025 |
| 314 | Kuehne Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 315 | Kunu Energy LLC | Wichita Falls, TX 76308 | Oil Operator | Mar 2025 |
| 316 | Kuran Resources | Wichita Falls, TX 76308 | Oil Operator | Mar 2025 |
| 317 | Kuykendall, M. C. | Electra, TX 76360 | Oil & Gas Operator | Apr 1995 |
| 318 | Kuykendall, M.C., Estate | Electra, TX 76360 | Oil & Gas Operator | Aug 2003 |
| 319 | L & J Oil | Gainesville, TX 76240 | Oil & Gas Operator | Nov 2000 |
| 320 | L & S Drilling, Inc. | Kamay, TX 76369 | Oil & Gas Operator | Mar 2016 |
| 321 | L And L Production Company | Skellytown, TX 79080 | Oil & Gas Operator | Sep 1996 |
| 322 | L L & M Properties, Inc. | Burkburnett, TX 76354 | Oil & Gas Operator | Aug 2004 |
| 323 | L-Texx Petroleum, LP | Arlington, TX 76013 | Oil & Gas Operator | Mar 2025 |
| 324 | L7 Energy LLC | Wichita Falls, TX 76308 | Oil Operator | Mar 2025 |
| 325 | Lackey, William H. Oil And Gas | Shawnee, OK 74804 | Oil & Gas Operator | Feb 2024 |
| 326 | Landrum Petroleum Co., Inc. | Burkburnett, TX 76354 | Oil Operator | Mar 2008 |
| 327 | Landrum West, Inc. | Burkburnett, TX 76354 | Oil & Gas Operator | Dec 1997 |
| 328 | Larance Engineering Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Jan 1996 |
| 329 | Layline Energy I LLC | Houston, TX 77024 | Oil & Gas Operator | Dec 2019 |
| 330 | LC Operating, LLC | Burkburnett, TX 76354 | Oil & Gas Operator | Mar 2025 |
| 331 | Leading Edge Energy LLC | San Antonio, TX 78205 | Oil Operator | Mar 2025 |
| 332 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 333 | Leonard Brothers Operating Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Mar 2025 |
| 334 | Lewis Operating Company | Holliday, TX 76366 | Oil & Gas Operator | Mar 2025 |
| 335 | Limestone Oil & Gas Co. | Wichita Falls, TX 76302 | Oil & Gas Operator | Jul 2002 |
| 336 | Lincoln Energy Partners, LLC | South Dennis, MA 02660 | Oil Operator | Mar 2025 |
| 337 | Lindemann, James D. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 338 | Lindemann, W. L., DRLG. Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jun 1994 |
| 339 | Lindemann, W.L., Oper. Co., Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2006 |
| 340 | Little, Quintin Company,Inc.,The | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2025 |
| 341 | LMH Energy | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 342 | Lode Holdings, LLC | Wichita Falls, TX 76301 | Oil Operator | Mar 2025 |
| 343 | Loveless Properties | Burkburnett, TX 76354 | Oil & Gas Operator | Apr 2021 |
| 344 | LTS Oil & Gas | Lubbock, TX 79424 | Oil & Gas Operator | Mar 2025 |
| 345 | LTS Oil & Gas A | Lubbock, TX 79424 | Oil & Gas Operator | Mar 2025 |
| 346 | Luke, D.L. Oil Co. | Burkburnett, TX 76354 | Oil & Gas Operator | Mar 2025 |
| 347 | Lunn, Will | Wichita Falls, TX 76301 | Oil & Gas Operator | Jun 1997 |
| 348 | M & A Oil Company, LTD. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 349 | M-2 Oil Company | Wichita Falls, TX 76306 | Oil & Gas Operator | May 2006 |
| 350 | Macha Enterprises, Inc. | Wichita Falls, TX 76309 | Oil Operator | Mar 2025 |
| 351 | Maddux Oil & Gas | Strawn, TX 76475 | Oil & Gas Operator | Mar 2025 |
| 352 | Magnum Production & Well Service | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 353 | Mandarin Oil & Gas Company | Austin, TX 78714 | Oil & Gas Operator | Mar 2025 |
| 354 | Maranatha Exploration, LP | Wichita Falls, TX 76307 | Oil Operator | Feb 2012 |
| 355 | Marshall Energy, Inc. | Dallas, TX 75243 | Oil & Gas Operator | May 1997 |
| 356 | Martis Valley Energy, LLC | Wichita Falls, TX 76310 | Oil Operator | Mar 2025 |
| 357 | Masa Energy LLC | Houston, TX 77094 | Oil & Gas Operator | Mar 2025 |
| 358 | Masada Oil & Gas | Quanah, TX 79252 | Oil & Gas Operator | Mar 2025 |
| 359 | Massie Oil Company | Graham, TX 76450 | Oil & Gas Operator | Mar 2025 |
| 360 | Maxwell, Richard | Wichita Falls, TX 76301 | Oil & Gas Operator | May 1995 |
| 361 | Mayo Oil Co. | San Antonio, TX 78209 | Oil & Gas Operator | Feb 2019 |
| 362 | MB Operating | Wichita Falls, TX 76309 | Oil & Gas Operator | Mar 2008 |
| 363 | McCauley Production | Graham, TX 76450 | Oil Operator | Mar 2025 |
| 364 | McClure Brothers | Denton, TX 76210 | Oil & Gas Operator | Mar 2025 |
| 365 | McClure Oil Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 366 | McCormick Operating, L.L.C. | Olney, TX 76374 | Oil Operator | Sep 2015 |
| 367 | McCulliss Resources Co Inc | Littleton, CO 80161-3248 | Oil & Gas Operator | Jun 2009 |
| 368 | McDay Energy Corp. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2025 |
| 369 | McDonald, Joe | Burkburnett, TX 76354 | Oil & Gas Operator | Aug 1995 |
| 370 | McKee, Kenneth W. Oil Co. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 371 | McLemore, Laurence | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 372 | Menasco, J. | Wichita Falls, TX 76310 | Oil & Gas Operator | Dec 2019 |
| 373 | Midnite Oil Co. | Wichita Falls, TX 76310 | Oil & Gas Operator | Mar 2025 |
| 374 | Midwestern Energy | Mankato, MN 56003 | Oil & Gas Operator | Mar 2025 |
| 375 | Miller, L. Joe & Bobby J. Parker | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2000 |
| 376 | Mink, Jay, Oil Co. | Electra, TX 76360 | Oil & Gas Operator | Aug 2017 |
| 377 | Mission Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 378 | Mitchell Drilling Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 2000 |
| 379 | Mitchell Oil Company | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 2000 |
| 380 | MJB Oil Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Mar 2025 |
| 381 | Mobil Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2016 |
| 382 | Mobil Producing TX. & N.M. Inc. | Spring, TX 77389 | Oil & Gas Operator | Mar 2025 |
| 383 | Moenning, Vernie | Electra, TX 76360 | Oil & Gas Operator | Mar 2025 |
| 384 | Mogul Operating LLC | St Petersburg, FL 33706 | Oil Operator | Mar 2025 |
| 385 | Moller, Herbert T. | Wichita Falls, TX 76301 | Oil & Gas Operator | Aug 2003 |
| 386 | Montgomery Petroleum, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2007 |
| 387 | Moore Energy Services, LLC | Iowa Park, TX 76367 | Oil Operator | Mar 2024 |
| 388 | Morton, J. V. Oil Co. | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 1999 |
| 389 | Mountain Creek Oil Company, Inc. | Saint Jo, TX 76265 | Oil & Gas Operator | Mar 2025 |
| 390 | MSB Operating | Wichita Falls, TX 76308 | Oil & Gas Operator | Mar 2025 |
| 391 | Muller Oil & Gas | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 2025 |
| 392 | Mullin, W. B. | Graham, TX 76450 | Oil & Gas Operator | Sep 1998 |
| 393 | Nance Engineering Inc. | Houston, TX 77058 | Oil & Gas Operator | Mar 2002 |
| 394 | NBL Permian LLC | Houston, TX 77070 | Oil & Gas Operator | Aug 2018 |
| 395 | Newberry, Charles D Inc | Campbellsvlle, KY 42719 | Oil Operator | Mar 2025 |
| 396 | Newport Operating, LLC | Burkburnett, TX 76354 | Oil Operator | Mar 2025 |
| 397 | NHRG Inc | Wichita Falls, TX 76308 | Oil Operator | Mar 2025 |
| 398 | Nichols Oil Co. | Holliday, TX 76366 | Oil & Gas Operator | Mar 2025 |
| 399 | Noc | Iowa Park, TX 76367 | Oil & Gas Operator | Dec 2020 |
| 400 | Nortex Production Co., LLC | Wichita Falls, TX 76310 | Oil Operator | Mar 2025 |