| 19201 | Monadnock Resources, LLC | Addison, TX 75001 | Oil & Gas Operator | May 2020 |
| 19202 | Monago Operating Inc | | Oil & Gas Operator | Apr 2007 |
| 19203 | Monahan | | Oil Operator | Dec 2009 |
| 19204 | Monahan Rex | Sterling, CO 80751 | Oil & Gas Operator | Jun 2002 |
| 19205 | Monahan* Rex Family Trust | | Oil & Gas Operator | May 2007 |
| 19206 | Monarch Energy C | | Oil Operator | Nov 1987 |
| 19207 | Monarch Energy Company LLC | Eufaula, OK 74432 | Oil & Gas Operator | Apr 2026 |
| 19208 | Monarch Energy LLC | Paola, KS 66071 | Oil Operator | Mar 2026 |
| 19209 | Monarch Operating Company | Graham, TX 76450 | Oil & Gas Operator | Jun 2006 |
| 19210 | Monarch Petroleum Corporation | FT Worth, TX 76102 | Oil & Gas Operator | Dec 2019 |
| 19211 | Moncrief Oil | Casper, WY 82602 | Oil & Gas Operator | Feb 1986 |
| 19212 | Moncrief R W Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1994 |
| 19213 | Moncrief W A Jr | Fort Worth, TX 76102 | Oil & Gas Operator | May 2026 |
| 19214 | Moncrief, C. B. | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 2021 |
| 19215 | Monday Creek Resources LTD | Logan, OH 43138 | Oil Operator | Dec 2025 |
| 19216 | Mondiale Energy, Inc. | Brownwood, TX 76801 | Oil & Gas Operator | Jul 2026 |
| 19217 | Mondo Operating Company | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2026 |
| 19218 | Monex | | Oil Operator | Apr 1988 |
| 19219 | Monexco | Edmond, OK 73034-3776 | Oil & Gas Operator | Mar 2008 |
| 19220 | Monexco LLC | Dallas, TX 75204-2634 | Oil & Gas Operator | Apr 2026 |
| 19221 | Monexco Operating Company | Dallas, TX 75204-2634 | Oil & Gas Operator | Apr 2026 |
| 19222 | Monexco, Inc. | | Oil Operator | Dec 2003 |
| 19223 | Monfort, Roy C. | Iola, KS 66749 | Oil & Gas Operator | Sep 1989 |
| 19224 | Monge Oil Corp. | | Oil & Gas Operator | Dec 2021 |
| 19225 | Mongoose Energy, LLC | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2026 |
| 19226 | Mongrue Oil Company, Inc. | | Oil & Gas Operator | Oct 1999 |
| 19227 | Mongrue, Roland, Inc | | Oil & Gas Operator | Mar 1979 |
| 19228 | Monitor O&G, L.L.C. | Frisco, TX 75034 | Oil & Gas Operator | Jan 2016 |
| 19229 | Monona LLC | Ligonier, PA 15658-0612 | Gas Operator | Apr 2026 |
| 19230 | Monroe Gas Associates-1 | | Gas Operator | Mar 2000 |
| 19231 | Monroe Gas Joint Venture | | Gas Operator | Sep 2011 |
| 19232 | Monroe James | | Oil & Gas Operator | Oct 1997 |
| 19233 | Monroe Natural Gas Inc | Norman, OK 73071 | Oil & Gas Operator | Apr 2026 |
| 19234 | Monroe Res LTD | Fairport, NY 14450-3218 | Gas Operator | Dec 2004 |
| 19235 | Monroe Well Ser-Amsterdam | | Oil Operator | Dec 1988 |
| 19236 | Monroe Well Ser-La Petr Assoc | | Oil Operator | Dec 1988 |
| 19237 | Monroe Well Ser-La Petro II | | Oil Operator | Dec 1988 |
| 19238 | Monroe Well Ser-New American85 | | Oil Operator | Dec 1988 |
| 19239 | Monroe Well Ser-Ocean Petr '84 | | Oil & Gas Operator | Dec 1988 |
| 19240 | Monroe Well Ser-Ocean Yacht II | | Oil Operator | May 1989 |
| 19241 | Monroe Well Ser-Oceanyacht1985 | | Oil Operator | Dec 1988 |
| 19242 | Monroe Well Ser-Riverside 1985 | | Oil Operator | Dec 1988 |
| 19243 | Monroe Well Serv-New American | | Oil Operator | Dec 1988 |
| 19244 | Monroe Well Serv-Northern La | | Oil Operator | Dec 1988 |
| 19245 | Monroe Well Serv-Omega 1985 | | Oil Operator | Dec 1988 |
| 19246 | Monroe Well Service | | Oil & Gas Operator | Apr 1998 |
| 19247 | Monroe Well Service-Ajk | | Oil Operator | Dec 1988 |
| 19248 | Monroe Well Service-Apk | | Oil Operator | Dec 1988 |
| 19249 | Monroe Well Service-Beaver1985 | | Oil Operator | Nov 1991 |
| 19250 | Monroe Well Service-Broadway | | Oil Operator | Dec 1988 |
| 19251 | Monroe Well Service-BWK | | Oil Operator | Dec 1988 |
| 19252 | Monroe Well Service-Columbus | | Oil Operator | Dec 1988 |
| 19253 | Monroe Well Service-Das | | Oil Operator | Mar 1989 |
| 19254 | Monroe Well Service-Derrick | | Oil Operator | Dec 1988 |
| 19255 | Monroe Well Service-East End | | Oil Operator | Dec 1988 |
| 19256 | Monroe Well Service-Empire | | Oil Operator | Dec 1988 |
| 19257 | Monroe Well Service-Energy | | Oil Operator | Dec 1988 |
| 19258 | Monroe Well Service-Energy 84 | | Oil Operator | Aug 1989 |
| 19259 | Monroe Well Service-Ged | | Oil Operator | Dec 1988 |
| 19260 | Monroe Well Service-Gotham | | Oil Operator | Apr 1992 |
| 19261 | Monroe Well Service-Gramercy | | Oil Operator | May 1992 |
| 19262 | Monroe Well Service-HGC | | Oil Operator | Dec 1988 |
| 19263 | Monroe Well Service-Lebo | | Oil Operator | Jun 1989 |
| 19264 | Monroe Well Service-Lexington | | Oil Operator | Feb 1989 |
| 19265 | Monroe Well Service-Newtown | | Oil Operator | Aug 1990 |
| 19266 | Monroe Well Service-Ocean | | Oil Operator | Feb 1989 |
| 19267 | Monroe Well Service-Oceanyacht | | Oil Operator | Jan 1989 |
| 19268 | Monroe Well Service-Oil City | | Oil Operator | Aug 1992 |
| 19269 | Monroe Well Service-Omega | | Oil Operator | Aug 1992 |
| 19270 | Monroe Well Service-Par | | Oil Operator | Jan 1990 |
| 19271 | Monroe Well Service-Petrol | | Oil Operator | Sep 1992 |
| 19272 | Monroe Well Service-Petrovest | | Oil Operator | Dec 1988 |
| 19273 | Monroe Well Service-PRG | | Oil Operator | Nov 1990 |
| 19274 | Monroe Well Service-Redstone | | Oil Operator | Jul 1989 |
| 19275 | Monroe Well Service-RVS | | Oil Operator | Dec 1990 |
| 19276 | Monroe Well Service-Shemen | | Oil Operator | Dec 1988 |
| 19277 | Monroe Well Service-Shemen1984 | | Oil Operator | Jan 1989 |
| 19278 | Monroe Well Service-Shemen1985 | | Oil Operator | Nov 1990 |
| 19279 | Monroe Well Service-Sla | | Oil Operator | Mar 1989 |
| 19280 | Monroe Well Service-SPD | | Oil Operator | Dec 1988 |
| 19281 | Monroe Well Service-SPD 1985 | | Oil Operator | Dec 1988 |
| 19282 | Monroe Well Service-TBR | | Oil Operator | Aug 1991 |
| 19283 | Monroe Well Service-TG I | | Oil Operator | Oct 1990 |
| 19284 | Monroe Well Service-TG II | | Oil Operator | Oct 1990 |
| 19285 | Monroe Well Service-TG III | | Oil Operator | Jul 1992 |
| 19286 | Monroe Well Service-TG VI | | Oil Operator | Aug 1989 |
| 19287 | Monroe Well Service-Tpa 1985 | | Oil Operator | Dec 1990 |
| 19288 | Monroe Well Service-Vista | | Oil Operator | Nov 1990 |
| 19289 | Monroe Well Service-West End | | Oil Operator | Dec 1988 |
| 19290 | Monroe Well Service-York | | Oil Operator | Dec 1988 |
| 19291 | Monroe, Cameron | Westfield, NY 14787 | Gas Operator | Dec 2025 |
| 19292 | Monsanto | Englewood, CO 80111 | Oil & Gas Operator | Apr 1986 |
| 19293 | Monsanto Company | Indianapolis, IN 46280 | Oil & Gas Operator | Jan 2005 |
| 19294 | Monsanto Oil Com | | Oil Operator | Nov 1996 |
| 19295 | Monsanto Oil Company | | Oil & Gas Operator | Apr 1986 |
| 19296 | Montalban Oil & Gas Operations, Inc. | Cut Bank, MT 59427 | Oil & Gas Operator | May 2026 |
| 19297 | Montana Energy Company, LLC | McAllen, TX 78504 | Oil & Gas Operator | Jan 2026 |
| 19298 | Montana Heartland LLC | Bismarck, ND 58504 | Oil & Gas Operator | Apr 2026 |
| 19299 | Montana Land & Exploration, Inc. | Calgary, AB T2P 3E7 | Oil & Gas Operator | Apr 2019 |
| 19300 | Montana Land & Mineral Co. | Billings, MT 59105 | Gas Operator | Mar 2026 |