| 301 | Moore, Brent L. | McPherson, KS 67460 | Oil Operator | Dec 1996 |
| 302 | Moore, Clay (Deceased) | Dallas, TX 75218 | Oil Operator | Sep 2001 |
| 303 | Moore, Douglas L. | Gridley, KS 66852 | Oil Operator | Jan 2019 |
| 304 | Mor-Meg Incorpor | | Oil Operator | Dec 1996 |
| 305 | Moran Oil Enterp | | Gas Operator | Apr 1989 |
| 306 | Moran Oil Enterprises LLC | Seminole, OK 74818 | Oil & Gas Operator | Dec 2019 |
| 307 | Morgenstern Oil Operations LLC | Ellinwood, KS 67526 | Oil Operator | Sep 2025 |
| 308 | Morris & Morris | | Oil Operator | Sep 1995 |
| 309 | Morris Bill Oil | | Gas Operator | Jan 1982 |
| 310 | Morris Everett E | | Oil & Gas Operator | Feb 1991 |
| 311 | Morris Oil Operations | | Oil Operator | Sep 2025 |
| 312 | Morris Richard B | | Oil Operator | Dec 1996 |
| 313 | Morrison, Mark L. | Yates Center, KS 66783 | Oil Operator | Sep 2025 |
| 314 | Morrison-Dixon O | | Oil Operator | Oct 1993 |
| 315 | Morrow, Joe | Farmington, NM 87401 | Oil Operator | Jan 1993 |
| 316 | Morsey Oil & Gas | | Oil & Gas Operator | Mar 1995 |
| 317 | Moss Petroleum Company | Dallas, TX 75207 | Oil & Gas Operator | Feb 2026 |
| 318 | Mountain Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Apr 2013 |
| 319 | Moylan, Thomas F. | Lacygne, KS 66040 | Oil & Gas Operator | Dec 1993 |
| 320 | MP Oil Operations | | Gas Operator | Dec 2004 |
| 321 | MSG Resources Inc. | Iola, KS 66749 | Oil Operator | Sep 2025 |
| 322 | MTM Petroleum, Inc. | Kingman, KS 67068 | Oil & Gas Operator | Sep 2025 |
| 323 | Muegge, Clay A. | Lamont, OK 74643 | Oil Operator | Aug 1991 |
| 324 | Mueller Oil | | Oil Operator | Jul 2025 |
| 325 | Mull Drilling Company | Wichita, KS 67206 | Oil & Gas Operator | Nov 2025 |
| 326 | Multiplex Resources, Inc. | Baytown, TX 77521 | Oil Operator | Dec 2009 |
| 327 | Multistate Oil P | | Gas Operator | Apr 1990 |
| 328 | Murchison Oil & | | Oil Operator | Mar 1988 |
| 329 | Murfin Drilling | | Oil & Gas Operator | Jul 1997 |
| 330 | Murfin Drilling Company, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Dec 2025 |
| 331 | Murjo Oil & Royalty Company | Fort Worth, TX 76121 | Oil & Gas Operator | Aug 2025 |
| 332 | Murk, James M. | Wheaton, IL 60189 | Gas Operator | Jan 1999 |
| 333 | Murphy, Charles H. | Altoona, KS 66710 | Oil Operator | Jul 2022 |
| 334 | Murphy, Earl M. | Madison, KS 66860 | Oil Operator | Jun 1999 |
| 335 | Murray Oil And Gas LLC | Greensburg, KS 67054 | Oil & Gas Operator | Sep 2025 |
| 336 | Musgrove Casey O | | Oil Operator | Oct 1993 |
| 337 | Musgrove Casey Oil | Ponca City, OK 74602-0391 | Oil & Gas Operator | Jun 2017 |
| 338 | Musgrove Energy Inc | Ponca City, OK 74602 | Oil & Gas Operator | Sep 2025 |
| 339 | Musgrove Petrole | | Oil & Gas Operator | Dec 1996 |
| 340 | Musgrove Produci | | Oil Operator | May 1989 |
| 341 | Musgrove Producing | El Dorado, KS 67042 | Oil Operator | Apr 2001 |
| 342 | Mustang Drilling | | Oil & Gas Operator | Nov 1996 |
| 343 | Mustang Drilling, Inc. | Henderson, TX 75653 | Oil & Gas Operator | Aug 2024 |
| 344 | Mustang Energy Corporation | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 345 | Mustang Fuel Cor | | Oil & Gas Operator | Dec 1990 |
| 346 | Mustang Fuel Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Dec 2025 |
| 347 | Mustang Oil & Gas Corporation | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2021 |
| 348 | MV Purchasing LLC | Wichita, KS 67206 | Oil & Gas Operator | Dec 2019 |
| 349 | MVRC Partnership | Russell, KS 67655 | Oil Operator | Jan 1992 |
| 350 | MW Oil, Inc | | Oil & Gas Operator | Sep 2025 |
| 351 | MWK Petroleum, LLC | Augusta, KS 67010 | Oil Operator | Sep 2025 |
| 352 | Myers Drilling And Exploration Inc. | Sedan, KS 67361 | Oil Operator | Aug 2022 |
| 353 | Myers Robert W J | | Oil Operator | Jun 1991 |
| 354 | Myers, Bobby | Cherryvale, KS 67335 | Oil & Gas Operator | Jun 2020 |
| 355 | Myers, Gus & Annie | Sedan, KS 67361 | Oil Operator | Aug 2017 |