| 3201 | Monroe Well Service-HGC | | Oil Operator | Dec 1988 |
| 3202 | Monroe Well Service-Lebo | | Oil Operator | Jun 1989 |
| 3203 | Monroe Well Service-Lexington | | Oil Operator | Feb 1989 |
| 3204 | Monroe Well Service-Newtown | | Oil Operator | Aug 1990 |
| 3205 | Monroe Well Service-Ocean | | Oil Operator | Feb 1989 |
| 3206 | Monroe Well Service-Oceanyacht | | Oil Operator | Jan 1989 |
| 3207 | Monroe Well Service-Oil City | | Oil Operator | Aug 1992 |
| 3208 | Monroe Well Service-Omega | | Oil Operator | Aug 1992 |
| 3209 | Monroe Well Service-Par | | Oil Operator | Jan 1990 |
| 3210 | Monroe Well Service-Petrol | | Oil Operator | Sep 1992 |
| 3211 | Monroe Well Service-Petrovest | | Oil Operator | Dec 1988 |
| 3212 | Monroe Well Service-PRG | | Oil Operator | Nov 1990 |
| 3213 | Monroe Well Service-Redstone | | Oil Operator | Jul 1989 |
| 3214 | Monroe Well Service-RVS | | Oil Operator | Dec 1990 |
| 3215 | Monroe Well Service-Shemen | | Oil Operator | Dec 1988 |
| 3216 | Monroe Well Service-Shemen1984 | | Oil Operator | Jan 1989 |
| 3217 | Monroe Well Service-Shemen1985 | | Oil Operator | Nov 1990 |
| 3218 | Monroe Well Service-Sla | | Oil Operator | Mar 1989 |
| 3219 | Monroe Well Service-SPD | | Oil Operator | Dec 1988 |
| 3220 | Monroe Well Service-SPD 1985 | | Oil Operator | Dec 1988 |
| 3221 | Monroe Well Service-TBR | | Oil Operator | Aug 1991 |
| 3222 | Monroe Well Service-TG I | | Oil Operator | Oct 1990 |
| 3223 | Monroe Well Service-TG II | | Oil Operator | Oct 1990 |
| 3224 | Monroe Well Service-TG III | | Oil Operator | Jul 1992 |
| 3225 | Monroe Well Service-TG VI | | Oil Operator | Aug 1989 |
| 3226 | Monroe Well Service-Tpa 1985 | | Oil Operator | Dec 1990 |
| 3227 | Monroe Well Service-Vista | | Oil Operator | Nov 1990 |
| 3228 | Monroe Well Service-West End | | Oil Operator | Dec 1988 |
| 3229 | Monroe Well Service-York | | Oil Operator | Dec 1988 |
| 3230 | Monsanto Company | Indianapolis, IN 46280 | Oil & Gas Operator | Jan 2005 |
| 3231 | Monsanto Oil Company | | Oil & Gas Operator | Apr 1986 |
| 3232 | Monte Carlo Exploration Inc. | | Oil & Gas Operator | Oct 1984 |
| 3233 | Monterey Pipeline Co. | | Oil Operator | Aug 1993 |
| 3234 | Monterey Resources LLC | Dallas, TX 75230 | Oil & Gas Operator | Oct 2019 |
| 3235 | Moon Operating, Inc. | Longview, TX 75601 | Oil & Gas Operator | Mar 2003 |
| 3236 | Moon-Hines-Tigrett Opr Co Inc | | Oil & Gas Operator | Oct 1995 |
| 3237 | Moore McCormack Energy, Inc. | | Oil & Gas Operator | Jul 1988 |
| 3238 | Moore Oil & Gas-Marion Corp. | | Oil & Gas Operator | Nov 1986 |
| 3239 | Moore&Munger Hydrocarbons Inc | | Oil Operator | May 1987 |
| 3240 | Mooringsport Energy Prod Corp | | Oil & Gas Operator | Oct 1994 |
| 3241 | Mooringsport Energy Trans Corp | | Oil Operator | Apr 1990 |
| 3242 | Mor-Co Investments, Inc. | | Gas Operator | Feb 1994 |
| 3243 | Moran Exploration, Inc. | | Oil & Gas Operator | Jan 1985 |
| 3244 | Moran Oil Co., Inc. | | Oil & Gas Operator | Aug 2009 |
| 3245 | Moransco Energy Corporation | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2026 |
| 3246 | Morgan Enterprises | | Oil & Gas Operator | Aug 1997 |
| 3247 | Moro Bay Oil Company, Inc. | | Oil Operator | Jan 1997 |
| 3248 | Mosbacher Energy Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2026 |
| 3249 | Moseley Petroleum Corp. | | Oil & Gas Operator | Apr 1988 |
| 3250 | MRD Operating LLC | | Oil & Gas Operator | Dec 2016 |
| 3251 | Mrs. C. M. Roberson | | Oil Operator | Mar 1989 |
| 3252 | Mrs. Cecile Andries & Sons | | Oil Operator | Dec 2006 |
| 3253 | Mrs. Clara B. Guthrie | | Gas Operator | Jun 1996 |
| 3254 | MRT Exploration Co | | Oil & Gas Operator | Feb 1983 |
| 3255 | MTBB Acquisition Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Aug 2022 |
| 3256 | Mullen Exploration Inc | | Oil & Gas Operator | Dec 2002 |
| 3257 | Mullins & Prichard | | Oil & Gas Operator | May 1992 |
| 3258 | Munday Operating Co., L.L.C. | | Oil & Gas Operator | May 2007 |
| 3259 | Munoco Company | El Dorado, AR 71730 | Oil & Gas Operator | Jul 2021 |
| 3260 | Murchison Oil & Gas Inc | Plano, TX 75024 | Oil & Gas Operator | Aug 2020 |
| 3261 | Murexco Petroleum Inc | Dallas, TX 75251 | Oil & Gas Operator | Oct 1996 |
| 3262 | Murphrey Oil Company, Inc. | | Oil Operator | Jan 2025 |
| 3263 | Murphy - Sun | | Oil & Gas Operator | May 1989 |
| 3264 | Murphy Exp & Prod Co.-USA | | Oil & Gas Operator | May 2014 |
| 3265 | Murphy Exploration & Prod. Co. | Houston, TX 77094 | Oil & Gas Operator | Jun 2011 |
| 3266 | Murphy Oil USA, Inc. | New Orleans, LA 70161 | Oil & Gas Operator | Jan 1993 |
| 3267 | Murray J. Evans | | Oil Operator | Mar 1985 |
| 3268 | Muslow And Parker | | Oil & Gas Operator | Jul 1994 |
| 3269 | Muslow Oil Industries | | Oil Operator | Jan 1995 |
| 3270 | Mustang Energy Inc. | Porter, TX 77365 | Oil & Gas Operator | Mar 2008 |
| 3271 | Mustang Energy L C | | Oil & Gas Operator | Jan 2013 |
| 3272 | MVM Resources Louisiana L.L.C. | | Oil & Gas Operator | Jan 2025 |
| 3273 | MVP Production Inc. | | Oil & Gas Operator | Apr 2005 |
| 3274 | MW Petroleum Corporation | Houston, TX 77056 | Oil & Gas Operator | Mar 2015 |
| 3275 | N And B Exploration, Inc. | | Oil & Gas Operator | Jun 1993 |
| 3276 | N Central Casing Pullers, Inc. | | Oil & Gas Operator | May 1994 |
| 3277 | N. B. Hunt | | Oil & Gas Operator | May 1981 |
| 3278 | N. E. Loomis | | Oil Operator | Oct 1986 |
| 3279 | N. J. Pardue | | Oil & Gas Operator | Jul 1994 |
| 3280 | N. R. Price | | Oil & Gas Operator | Nov 1983 |
| 3281 | N. T. Rutledge Oil Co. | | Oil Operator | Jan 1989 |
| 3282 | N. W. Corporation | | Gas Operator | Jan 1989 |
| 3283 | Nabors Drilling Company, Inc. | | Oil & Gas Operator | Sep 1977 |
| 3284 | Nabors Well Services LTD | Houston, TX 77067-4536 | Oil Operator | Apr 2011 |
| 3285 | Nabors-Johnson Prod Co., Inc. | | Oil & Gas Operator | Dec 2020 |
| 3286 | Nacatosh Gas Incorporated | | Oil & Gas Operator | Aug 2013 |
| 3287 | Nadel & Gussman | Tulsa, OK 74103 | Oil & Gas Operator | May 2007 |
| 3288 | Nadel & Gussman-Jetta Oper. Co. | | Oil & Gas Operator | Mar 2012 |
| 3289 | Nadel And Gussman LLC | Tulsa, OK 74119 | Oil & Gas Operator | Feb 2026 |
| 3290 | Nadel And Gussman Ruston, LLC | | Oil & Gas Operator | Dec 2024 |
| 3291 | Nasser Oil & Gas, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 1998 |
| 3292 | Nat. Gas Pipeline Co Of Amer. | | Oil Operator | Dec 2008 |
| 3293 | Nathan C. Hale | | Oil & Gas Operator | Jan 2025 |
| 3294 | Nathan Hale Oil Co. | | Oil & Gas Operator | Jan 2025 |
| 3295 | National Energy Group Inc | Dallas, TX 75206 | Oil & Gas Operator | Sep 2014 |
| 3296 | National Exploration Company | | Oil & Gas Operator | Mar 1982 |
| 3297 | National Offshore LP | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2008 |
| 3298 | Natomas North America Inc | | Oil & Gas Operator | Aug 1993 |
| 3299 | Natomas-McCormick-Coastal | | Oil & Gas Operator | Feb 1984 |
| 3300 | Natural Gas Systems, Inc. | | Oil & Gas Operator | Dec 2002 |