| 201 | McIntyre M L | Oklahoma City, OK 73154-0523 | Oil & Gas Operator | Jul 1996 |
| 202 | McKay Oil Company | Perry, OK 73077 | Oil Operator | Nov 2008 |
| 203 | McKee Energy Comapny Inc | | Oil & Gas Operator | Apr 2011 |
| 204 | McKenzie Petroleum Company | Houston, TX 77063 | Oil & Gas Operator | Aug 1995 |
| 205 | McKinney Kenneth R | Okmulgee, OK 74447-6932 | Oil Operator | Aug 2000 |
| 206 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 207 | MCM Energy Inc | Edmond, OK 73013-8035 | Oil & Gas Operator | Nov 2021 |
| 208 | McMahon Operating Co., L.C. | Pampa, TX 79066 | Oil & Gas Operator | Dec 2004 |
| 209 | McMillin C C & Company Inc | Guthrie, OK 73044 | Oil & Gas Operator | Jan 2026 |
| 210 | McMurtrie Oil Inc | | Oil & Gas Operator | Jan 2026 |
| 211 | McNeal Production Inc | Perry, OK 73077-0268 | Oil & Gas Operator | Nov 2014 |
| 212 | McNic Oil & Gas Midcontinent | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | May 2024 |
| 213 | McNutt P L | San Marcos, CA 92069-4817 | Oil & Gas Operator | Jul 1994 |
| 214 | McO Resources Integrated Corp | Houston, TX 77057 | Oil Operator | Jan 1997 |
| 215 | McOil Operating Company LLC | Muskogee, OK 74401 | Oil & Gas Operator | Jan 2026 |
| 216 | McOr Oil & Gas Corp | Houston, TX 77002 | Oil & Gas Operator | Oct 2013 |
| 217 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 218 | McRae & Henry LTD | Golden, CO 80401 | Oil & Gas Operator | May 2022 |
| 219 | Me3 Oilfield Service LLC | Tulsa, OK 74136-1236 | Oil & Gas Operator | Feb 2026 |
| 220 | Meade Energy Corporation | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Feb 2026 |
| 221 | Meade James C | Oklahoma City, OK 73118-1544 | Gas Operator | Apr 2015 |
| 222 | Meador Hubbell Meador Inc | Beggs, OK 74421-0794 | Oil & Gas Operator | Apr 2020 |
| 223 | Meador Oil Company Inc | Lubbock, TX 79415 | Oil & Gas Operator | Oct 2022 |
| 224 | Meadors Jr J W Trust | Bixby, OK 74008-0151 | Oil & Gas Operator | Aug 2013 |
| 225 | Meadors Operating Co | Jennings, OK 74038-0233 | Oil Operator | Feb 2026 |
| 226 | Meadowbrook Oil Corporation Of Ok Inc | Del City, OK 73115-3608 | Oil & Gas Operator | Feb 2026 |
| 227 | Meadowlark Operating Co | | Oil & Gas Operator | Feb 2026 |
| 228 | Mecom Energy Corporation | Houston, TX 77030 | Oil & Gas Operator | Jan 1999 |
| 229 | Medallion Energy Inc | Norman, OK 73072-7436 | Oil & Gas Operator | Aug 2004 |
| 230 | Medallion Petroleum, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2015 |
| 231 | Medders Oil Company | Wichita Falls, TX 76308 | Oil & Gas Operator | May 2026 |
| 232 | Medicine Bow Operating Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2014 |
| 233 | Mega Resources Inc | Dallas, TX 75225-0186 | Oil & Gas Operator | Jan 2001 |
| 234 | Megaenergy Operating, Inc. | Edmond, OK 73034 | Oil & Gas Operator | Jul 2015 |
| 235 | Megargel Drilling Company | Megargel, TX 76370 | Oil Operator | Nov 1998 |
| 236 | Mel Cox Transports Inc | Comanche, OK 73529-7640 | Oil & Gas Operator | Jul 2022 |
| 237 | Mel-Ray Oil Company | Nowata, OK 74048-0149 | Oil & Gas Operator | Mar 2004 |
| 238 | Melson Oil & Gas Inc | Broken Arrow, OK 74014 | Oil & Gas Operator | Feb 2026 |
| 239 | Melzer Exploration Company | Midland, TX 79702-2083 | Oil & Gas Operator | May 2013 |
| 240 | Mendell Petroleum Corporation | Castle Rock, CO 80104-9045 | Oil & Gas Operator | Sep 2004 |
| 241 | Mep Operating LLC | Houston, TX 77056-2733 | Oil & Gas Operator | Aug 2025 |
| 242 | Mer Resources Inc | Edmond, OK 73013-7662 | Oil & Gas Operator | Mar 2015 |
| 243 | Mercer Oil And Gas Co Inc | Norman, OK 73070 | Oil & Gas Operator | Apr 2015 |
| 244 | Mercer Pet Management Inc | Edmond, OK 73013-6677 | Oil & Gas Operator | Jan 2011 |
| 245 | Merelco Inc | Seminole, OK 74868 | Oil Operator | Jun 2014 |
| 246 | Merex Resources, Inc. | Amarillo, TX 79159 | Oil & Gas Operator | Sep 2019 |
| 247 | Meridian Exploration Inc | Oklahoma City, OK 73128 | Oil & Gas Operator | Aug 2013 |
| 248 | Meridian Oil Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 1996 |
| 249 | Meridian Oil Production Inc. | Houston, TX 77210 | Oil & Gas Operator | Aug 2024 |
| 250 | Merit Energy Company | Dallas, TX 75240 | Oil & Gas Operator | May 2026 |
| 251 | Mermac Operating Company Inc | Norman, OK 73072 | Oil & Gas Operator | Mar 2015 |
| 252 | Meroda Resources LLC | Mustang, OK 73064-9408 | Oil & Gas Operator | Apr 2000 |
| 253 | Merrick Ward S Inc | Ardmore, OK 73402 | Oil & Gas Operator | Feb 2001 |
| 254 | Mervine Oil Company Inc | Blackwell, OK 74631-0514 | Oil Operator | Jan 2013 |
| 255 | Mesa Exploration Company Inc | Shawnee, OK 74801 | Oil & Gas Operator | Feb 2026 |
| 256 | Mesa Operating LP | Irving, TX 75039-3746 | Oil & Gas Operator | Oct 2010 |
| 257 | Metro Energy Group, Inc. | Bossier City, LA 71112 | Oil & Gas Operator | May 2013 |
| 258 | Metro Energy LTD | Scottsdale, AZ 85254 | Oil Operator | Aug 2000 |
| 259 | Metropolitan Resources Corp | Tulsa, OK 74169-1734 | Oil & Gas Operator | Mar 2015 |
| 260 | Metzner, Norma J. Estate | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 1998 |
| 261 | Mewbourne Marketing, Inc. | | Oil & Gas Operator | Mar 2013 |
| 262 | Mewbourne Oil Company | Tyler, TX 75711 | Oil & Gas Operator | May 2026 |
| 263 | Meyer Oil Co., Inc. | Skellytown, TX 79080 | Oil & Gas Operator | Feb 2026 |
| 264 | Meyerhoff & Cox Inc | Tulsa, OK 74135-7830 | Oil Operator | Aug 1993 |
| 265 | MFP Petroleum LP | Oklahoma City, OK 73142-3017 | Gas Operator | Jan 2026 |
| 266 | Mge Resources, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Jan 2026 |
| 267 | MGF Oil Corporation | Tulsa, OK 74121 | Oil & Gas Operator | Jun 1998 |
| 268 | Michael Goodnight Operating LLC | St Louis, OK 74866 | Oil & Gas Operator | Feb 2026 |
| 269 | Michigan Oil Company | FT Worth, TX 76117 | Oil & Gas Operator | Feb 1998 |
| 270 | Mickalson Operating Company | Cleveland, OK 74020 | Oil & Gas Operator | Feb 2026 |
| 271 | Mid Center Oil Company | | Oil & Gas Operator | Mar 2014 |
| 272 | Mid-Con Central Expl Co | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2014 |
| 273 | Mid-Con Energy Operating, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | May 2020 |
| 274 | Mid-Con Energy Operating, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2026 |
| 275 | Mid-Continent Energy Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2026 |
| 276 | Mid-Continent Petroleum Management Inc | Cement, OK 73017 | Oil & Gas Operator | Feb 2026 |
| 277 | Mid-Way Environmental Services Inc | Stroud, OK 74079 | Oil Operator | Apr 2025 |
| 278 | Midcontinent Oil & Gas Company | Phoenix, AZ 85022-6180 | Oil & Gas Operator | Jun 2012 |
| 279 | Middle Bay Production Co. Inc. | Houston, TX 77010 | Oil & Gas Operator | Sep 2014 |
| 280 | Midgard Energy Company | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2014 |
| 281 | Midland TMG Inc. | Midland, TX 79705 | Oil & Gas Operator | Apr 2017 |
| 282 | Midnight Energy Operating LLC | Sand Springs, OK 74063 | Oil Operator | Feb 2026 |
| 283 | Midnight Hour LLC | Enid, OK 73702 | Oil & Gas Operator | Apr 2020 |
| 284 | Midstate Oil & Gas Company | Shawnee, OK 74801 | Oil & Gas Operator | Jan 2026 |
| 285 | Midstates Oil Company | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2000 |
| 286 | Midway Leasing Inc | Haskell, OK 74436-2406 | Oil & Gas Operator | Jan 2024 |
| 287 | Midway Operating Company, L.L.C. | Woodward, OK 73802 | Oil & Gas Operator | May 2026 |
| 288 | Midwest Energy Corporation | Tulsa, OK 74105-6083 | Oil & Gas Operator | Aug 2016 |
| 289 | Midwest Enterprises Inc | Cashion, OK 73016-9626 | Oil & Gas Operator | Apr 2025 |
| 290 | Midwest Eor Inc | Tulsa, OK 74105-6059 | Oil & Gas Operator | May 2013 |
| 291 | Midwest Oil Company | Beggs, OK 74421-2976 | Oil Operator | Apr 2015 |
| 292 | Midwest Operating Company Inc | Tulsa, OK 74105-6059 | Oil & Gas Operator | Nov 1999 |
| 293 | Midwest Pipe & Supply Company | Oklahoma City, OK 73154-0245 | Oil & Gas Operator | Dec 2008 |
| 294 | Midwestern Exploration Company | Edmond, OK 73013 | Oil & Gas Operator | May 2025 |
| 295 | Migwis Operating LLC | Cushing, OK 74023-4854 | Oil & Gas Operator | Oct 2020 |
| 296 | Mija LLC | Oklahoma City, OK 73151 | Oil & Gas Operator | Feb 2026 |
| 297 | Mikal R Brown Oil LLC | Cleveland, OK 74020-6475 | Oil Operator | Dec 2022 |
| 298 | Mikarden Energy Inc | Sapulpa, OK 74066 | Oil Operator | Jan 2026 |
| 299 | Mikco Inc | Tulsa, OK 74133 | Oil & Gas Operator | May 2001 |
| 300 | Milagro Exploration, LLC | Houston, TX 77010 | Oil & Gas Operator | Aug 2018 |