| 2201 | Mountaineer State Operations, LLC | Sandyville, WV 25275 | Oil & Gas Operator | Dec 2025 |
| 2202 | Mountaineer Trading Company, LLC | Charleston, WV 25314 | Oil & Gas Operator | Dec 2016 |
| 2203 | Mountainside Energy Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Jul 2026 |
| 2204 | Mourning James & Carol | Middleport, OH 45760-1214 | Gas Operator | Dec 2024 |
| 2205 | Mowata Oil Company | Victoria, TX 77903 | Oil & Gas Operator | Oct 1996 |
| 2206 | Moxy Oil Company | Seguin, TX 78155 | Oil & Gas Operator | Aug 2003 |
| 2207 | Moy, Gary | Falls City, TX 78113 | Oil & Gas Operator | Nov 1998 |
| 2208 | Moylan, Jimmie C. | Eastland, TX 76448 | Oil & Gas Operator | Jul 2026 |
| 2209 | Moylan, Thomas F. | Lacygne, KS 66040 | Oil & Gas Operator | Dec 1993 |
| 2210 | Mozark Corporation | Spring, TX 77379-8049 | Oil & Gas Operator | Jan 2011 |
| 2211 | Moze Inc | Ochelata, OK 74051 | Oil & Gas Operator | Jan 2001 |
| 2212 | MPG Petroleum | San Antonio, TX 78217 | Oil & Gas Operator | Aug 2003 |
| 2213 | MPG Petroleum, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2026 |
| 2214 | Mr NM Operating LLC | Dallas, TX 75225 | Oil & Gas Operator | May 2026 |
| 2215 | Mr Oil Company | Monahans, TX 79756 | Oil & Gas Operator | Nov 2004 |
| 2216 | MRD Nowata LLC | Woodstock, GA 30189 | Oil Operator | Aug 2017 |
| 2217 | MRD Operating LLC | | Oil & Gas Operator | Dec 2016 |
| 2218 | MRD Operating LLC (Delaware) | Houston, TX 77010 | Oil & Gas Operator | Jul 2015 |
| 2219 | Mri Ventures, Inc. | | Oil Operator | Dec 1993 |
| 2220 | Mroz Baier, Christine | Memphis, TN 38120 | Gas Operator | Dec 2025 |
| 2221 | MRR Oil Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jun 2002 |
| 2222 | Mrs. C. M. Roberson | | Oil Operator | Mar 1989 |
| 2223 | Mrs. Cecile Andries & Sons | | Oil Operator | Dec 2006 |
| 2224 | MRT Exploration Co | | Oil & Gas Operator | Feb 1983 |
| 2225 | MS Producing LLC | Creston, OH 44217 | Oil & Gas Operator | Dec 2025 |
| 2226 | MS United, LLC | | Oil & Gas Operator | Apr 2026 |
| 2227 | MSB Operating | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2026 |
| 2228 | MSB Operating Company | Enid, OK 73703 | Oil & Gas Operator | Jan 2005 |
| 2229 | MSD Energy, Inc | Rapid City, SD 57702 | Oil & Gas Operator | Dec 2020 |
| 2230 | MSD Operating, LLC | Big Spring, TX 79721 | Oil & Gas Operator | Jul 2026 |
| 2231 | Mse Operating Corp. | Beaverton, OR 97008 | Oil & Gas Operator | Jul 2026 |
| 2232 | MSG Resources Inc. | Iola, KS 66749 | Oil Operator | Mar 2026 |
| 2233 | MSL Oil & Gas Corp | Bradford, PA 16701-0151 | Oil & Gas Operator | Dec 2025 |
| 2234 | MSN Oil, Inc. | Avoca, TX 79503 | Oil Operator | Jul 2026 |
| 2235 | MSR Exploration, Inc. | Winters, TX 79567 | Oil & Gas Operator | Mar 2000 |
| 2236 | MSSK Consulting LLC | San Antonio, TX 78253 | Oil Operator | Jul 2026 |
| 2237 | MT Dora Energy Corporation | Duncan, OK 73533-1829 | Oil & Gas Operator | Apr 2014 |
| 2238 | MT Dora Energy LLC | Houston, OK 77056-1940 | Oil & Gas Operator | Jun 2019 |
| 2239 | MT Energy LLC | Waskom, TX 75692 | Oil & Gas Operator | Jul 2026 |
| 2240 | MT Savage Refractories | Pittsburgh, PA 15206-0171 | Gas Operator | Dec 2021 |
| 2241 | MT. Crescent Operating Company, LLC | | Oil & Gas Operator | Jun 2026 |
| 2242 | MTBB Acquisition Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Aug 2022 |
| 2243 | MTG Operating Inc | Ridgeland, MS 39158 | Gas Operator | Apr 2011 |
| 2244 | MTM Petroleum, Inc. | Kingman, KS 67068 | Oil & Gas Operator | Mar 2026 |
| 2245 | MTN Energy | Aleppo, PA 15310 | Oil & Gas Operator | Apr 2026 |
| 2246 | MTN V Oil & Gas Inc | | Oil & Gas Operator | Apr 2026 |
| 2247 | Mto Oil Company | Okay, OK 74446-0354 | Oil Operator | Jul 2019 |
| 2248 | Muckleroy Gas | San Antonio, TX 78247 | Gas Operator | Jul 2026 |
| 2249 | Mud Creek Operating, LLC | Tyler, TX 75702 | Oil & Gas Operator | Jul 2026 |
| 2250 | Mud Operations Inc | Ames, OK 73718-9501 | Oil & Gas Operator | May 2026 |
| 2251 | Mud River Oil & Gas, LLC | Rochester, KY 42273 | Oil Operator | Dec 2023 |
| 2252 | Mudslinger Oil, L.L.C. | Abilene, TX 79601 | Oil Operator | Jul 2026 |
| 2253 | Muegge Don E | Lamont, OK 74643-5010 | Oil & Gas Operator | Dec 1996 |
| 2254 | Muegge, Clay A. | Lamont, OK 74643 | Oil Operator | Aug 1991 |
| 2255 | Mueggenborg Derrick R Dba DRM Oil & Gas | Yale, OK 74085 | Oil Operator | May 2026 |
| 2256 | Mueller Engineering Corp. | Corpus Chrsti, TX 78476 | Oil & Gas Operator | Feb 2002 |
| 2257 | Mueller Exploration, Inc. | Humble, TX 77346 | Oil & Gas Operator | Jul 2026 |
| 2258 | Mueller Fred W | | Oil & Gas Operator | Dec 1995 |
| 2259 | Mueller Oil | | Oil Operator | Mar 2026 |
| 2260 | Mueller Thomas C | Fort Smith, AR 72913 | Gas Operator | Aug 2008 |
| 2261 | Mueller Thomas C LTD | Oklahoma City, OK 73102-5683 | Gas Operator | Aug 2008 |
| 2262 | Muenster Drilling Co. Inc. | Muenster, TX 76252 | Oil & Gas Operator | Jul 2026 |
| 2263 | Muffoletto, Michael R. | Brant, NY 14027 | Gas Operator | Dec 2025 |
| 2264 | Mugg, John D. Jr. | San Antonio, TX 78216 | Oil & Gas Operator | Nov 1997 |
| 2265 | Muirfield Exploration, LTD. | Wichita Falls, TX 76301 | Oil & Gas Operator | Jul 2026 |
| 2266 | Muirfield Resources Company | Tulsa, OK 74101-3166 | Oil & Gas Operator | Jun 2024 |
| 2267 | Muldowney Development, Inc. | Dunkirk, NY 14048 | Gas Operator | Dec 2025 |
| 2268 | Mule Kick Operating LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2026 |
| 2269 | Muleshoe Crude, LP | Midland, TX 79701 | Oil & Gas Operator | Jul 2026 |
| 2270 | Mull Drilling Company | Wichita, KS 67206 | Oil & Gas Operator | Apr 2026 |
| 2271 | Mullen Exploration Inc | | Oil & Gas Operator | Dec 2002 |
| 2272 | Mullen Resources LLC | Reedy, WV 25270 | Oil & Gas Operator | Dec 2021 |
| 2273 | Mullen William Company | Edmond, OK 73083-1372 | Oil & Gas Operator | May 1999 |
| 2274 | Mullen-Hathorn-Bass | | Oil & Gas Operator | Mar 1985 |
| 2275 | Muller Oil & Gas | Wichita Falls, TX 76307 | Oil & Gas Operator | Jul 2026 |
| 2276 | Mullin, W. B. | Graham, TX 76450 | Oil & Gas Operator | Sep 1998 |
| 2277 | Mullins & Prichard | | Oil & Gas Operator | May 1992 |
| 2278 | Mullins Jimmy R Dba Southcreek Petroleum Co | Dibble, OK 73031 | Oil & Gas Operator | Jan 2021 |
| 2279 | Mullins Well Service | MT Gilead, OH 43338 | Oil & Gas Operator | Dec 2018 |
| 2280 | Mullins, John S | | Oil Operator | Nov 2014 |
| 2281 | Mullins, Manuel | Olney, TX 76374 | Oil & Gas Operator | Jul 2026 |
| 2282 | Mulloy Operating, Inc. | Midland, TX 79707 | Oil & Gas Operator | Jul 2026 |
| 2283 | Mulloy, J. W. Associates, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2003 |
| 2284 | Multipay Energy, Inc. | Austin, TX 78749 | Oil Operator | Jul 2026 |
| 2285 | Multiplex Resources, Inc. | Baytown, TX 77521 | Oil Operator | Dec 2009 |
| 2286 | Mumford, Catherine | Waterloo, NY 13165 | Gas Operator | Dec 2025 |
| 2287 | Mumford-Gabel, Jennifer And Kyle Gabel | Lawtons, NY 14091 | Gas Operator | Dec 2025 |
| 2288 | Mumma Oil Production Co., Inc. | Allentown, PA 18109-0000 | Oil & Gas Operator | Dec 2019 |
| 2289 | Munday Operating Co., L.L.C. | | Oil & Gas Operator | May 2007 |
| 2290 | Mundell F E | Watertown, SD 57201 | Oil & Gas Operator | Aug 1994 |
| 2291 | Munn, W. H. Operating Company | Midland, TX 79702 | Oil & Gas Operator | Sep 2002 |
| 2292 | Munoco Co. L.C. | | Oil & Gas Operator | Jun 2003 |
| 2293 | Munoco Company | El Dorado, AR 71730 | Oil & Gas Operator | Jul 2021 |
| 2294 | Munoz Farms Operating Co., LLC | Carrizo SPGS, TX 78834 | Oil & Gas Operator | Jul 2026 |
| 2295 | Munoz, Magdaleno C. | Borger, TX 79007 | Oil Operator | Jul 2026 |
| 2296 | Munson Dave Company | Dallas, TX 75201-3591 | Oil Operator | Aug 1996 |
| 2297 | Munson Operating, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Jul 2026 |
| 2298 | Munson, Charles C. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2002 |
| 2299 | Munson, David M. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2015 |
| 2300 | Munson, David M. Inc. | Dallas, TX 75251 | Oil & Gas Operator | Jul 2026 |