| 18201 | Marieff Petroleum, Inc. | Sagamore Hills, OH 44067 | Gas Operator | Dec 2024 |
| 18202 | Marienfeld Exploration | Houston, TX 77005 | Oil & Gas Operator | Mar 1994 |
| 18203 | Marienfeld Exploration, Inc. | Ojai, CA 93024 | Oil & Gas Operator | Dec 2025 |
| 18204 | Marietta Royalty Co Inc | Stillwater, OK 74076 | Oil & Gas Operator | Dec 1986 |
| 18205 | Marina Pacifica Oil Company | | Oil & Gas Operator | Dec 1981 |
| 18206 | Marine Cont. & Supply Inc. | | Oil & Gas Operator | Nov 1985 |
| 18207 | Marine Properties, Inc. | | Oil & Gas Operator | Feb 1995 |
| 18208 | Mariner Energy, Inc. | Houston, TX 77042 | Oil & Gas Operator | Nov 2010 |
| 18209 | Marino, Charles B. | Tomball, TX 77377 | Oil & Gas Operator | Dec 2025 |
| 18210 | Marion Corporation | | Oil & Gas Operator | Jan 2001 |
| 18211 | Marion County Prod. Co., L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 18212 | Marion Energy Inc | Houston, TX 770082292 | Oil & Gas Operator | May 2015 |
| 18213 | Marion Operating Corp | Marion, OH 43301 | Oil & Gas Operator | Dec 2020 |
| 18214 | Mariposa Petroleum Co. | | Gas Operator | Dec 1980 |
| 18215 | Maritech Resources, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2009 |
| 18216 | Maritech Resources, LLC | | Oil & Gas Operator | May 2011 |
| 18217 | Marjac Energy Co | Bremen, OH 43107 | Oil & Gas Operator | Dec 1986 |
| 18218 | Marjac Oil Company, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2025 |
| 18219 | Marjo Incorporat | | Oil & Gas Operator | Jun 1990 |
| 18220 | Marjo Oil Company | Lockhart, TX 78644 | Oil & Gas Operator | Oct 1999 |
| 18221 | Marjo Operating Company Inc | Tulsa, OK 741010729 | Oil & Gas Operator | Aug 2025 |
| 18222 | Marjo Operating Mid-Continent LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2025 |
| 18223 | Marjo, Inc. | | Oil & Gas Operator | Sep 1991 |
| 18224 | Mark & Troy Johnson | Sugar Grove, PA 16350-5938 | Oil Operator | Dec 2024 |
| 18225 | Mark A & Michael J Midlik | Warren, PA 16365-2029 | Oil & Gas Operator | Dec 2015 |
| 18226 | Mark A Meier Dba MSC Oil And Gas Co | Oklahoma City, OK 73105 | Oil & Gas Operator | Jul 2025 |
| 18227 | Mark F Preddy & Associates,Inc | | Oil & Gas Operator | Dec 1987 |
| 18228 | Mark Holloway Inc | Oklahoma City, OK 73107-6526 | Oil & Gas Operator | Aug 2025 |
| 18229 | Mark I Oil Company | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 18230 | Mark III Oil, Inc. | Wichita, KS 67206 | Oil Operator | Dec 2009 |
| 18231 | Mark IV Energy | San Antonio, TX 78213 | Oil & Gas Operator | Apr 1993 |
| 18232 | Mark L Shidler Inc | Houston, TX 77055 | Oil & Gas Operator | Sep 2025 |
| 18233 | Mark Oil, Inc. | Chanute, KS 66720 | Oil Operator | Feb 2025 |
| 18234 | Mark Petroleum Inc | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2018 |
| 18235 | Mark Producing Inc | Houston, TX 77057 | Oil & Gas Operator | Dec 1987 |
| 18236 | Mark Resources Corp | Pittsburgh, PA 15276 | Oil & Gas Operator | Dec 1993 |
| 18237 | Mark Seifer | | Oil & Gas Operator | Dec 2024 |
| 18238 | Mark T. Kellner Oil Co. | Olean, NY 14760 | Oil & Gas Operator | Dec 2024 |
| 18239 | Mark V Petroleum Company | | Oil & Gas Operator | Feb 2020 |
| 18240 | Markan Oil Incor | | Oil Operator | Mar 1991 |
| 18241 | Markay Oil & Gas Company | Midland, TX 79701 | Oil & Gas Operator | Sep 1998 |
| 18242 | Marker Oil Compa | | Oil Operator | Jul 1985 |
| 18243 | Market Street Energy, Inc. | Flatonia, TX 78941 | Oil & Gas Operator | Dec 2025 |
| 18244 | Markham, Charles A., Jr. & Janet E. | Gowanda, NY 14070 | Gas Operator | Dec 2024 |
| 18245 | Markley Exploration | Bixby, OK 74008-5332 | Oil & Gas Operator | Jan 2014 |
| 18246 | Markley L C Corporation | Fletcher, OK 73541 | Oil & Gas Operator | Aug 2002 |
| 18247 | Marks & Co., Inc. | | Oil & Gas Operator | Dec 2021 |
| 18248 | Marks And Garner Production LTD Co | Hobbs, NM 88241 | Oil & Gas Operator | Sep 2010 |
| 18249 | Marks Operating LLC | | Oil & Gas Operator | Jul 2016 |
| 18250 | Marksmen Energy USA Inc | Worthington, OH 43085-1270 | Oil Operator | Dec 2023 |
| 18251 | Markus Production | Littleton, CO 80123 | Oil & Gas Operator | Oct 2025 |
| 18252 | Markus Production, Inc | | Oil & Gas Operator | Mar 2021 |
| 18253 | Markwest Resources Inc | Englewood, CO 801125004 | Oil & Gas Operator | Jun 2003 |
| 18254 | Marlan Anderson | | Oil Operator | Jan 2025 |
| 18255 | Marler Philip | Purcell, OK 73080-1522 | Oil & Gas Operator | Nov 2016 |
| 18256 | Marlin And Davis | | Oil Operator | Sep 1987 |
| 18257 | Marlin Coastal, L.L.C. | | Oil & Gas Operator | Apr 2008 |
| 18258 | Marlin Energy Offshore, L.L.C. | | Oil & Gas Operator | Jun 2006 |
| 18259 | Marlin Energy Resources, LLC | Lafayette, LA 70503 | Oil & Gas Operator | May 2018 |
| 18260 | Marlin Energy Southwest GP, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Dec 2025 |
| 18261 | Marlin Expl.,Inc&Exchg O&G Co | | Oil & Gas Operator | Jun 1987 |
| 18262 | Marlin Exploration, Inc. | | Oil & Gas Operator | Oct 2006 |
| 18263 | Marlin Exploration, LLC | | Oil & Gas Operator | Sep 2025 |
| 18264 | Marlin Oil Company LLC | Gillette, WY 82718 | Oil & Gas Operator | Mar 2023 |
| 18265 | Marlin Oil Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Aug 2025 |
| 18266 | Marlin Operating, LLC | Southlake, TX 76092 | Oil & Gas Operator | Sep 2025 |
| 18267 | Marlin Pacific Oil & Gas | | Oil & Gas Operator | Dec 2003 |
| 18268 | Marlin Resources, L.L.C. | Midland, TX 79702 | Oil & Gas Operator | Jan 2025 |
| 18269 | Marlin, Bruce W | | Oil Operator | Aug 2025 |
| 18270 | Marline Oil Corp | Houston, TX 77002 | Oil & Gas Operator | Dec 1989 |
| 18271 | Marline Petroleum Corporation | | Oil & Gas Operator | Dec 1985 |
| 18272 | Marlow Environmental LLC | Marlow, OK 73055 | Oil Operator | May 2022 |
| 18273 | Marlyn Company | | Oil & Gas Operator | Dec 2009 |
| 18274 | Marmac Petroleum | | Oil & Gas Operator | Oct 1994 |
| 18275 | Marmac Petroleum Company | Denver, CO 80222 | Oil Operator | Apr 1998 |
| 18276 | Marmac Resources Company | | Oil & Gas Operator | Mar 2015 |
| 18277 | Marmac Resources Inc | | Oil Operator | Nov 1998 |
| 18278 | Marmaton Oil Company | Houston, TX 77002 | Oil & Gas Operator | Jul 1998 |
| 18279 | Marmik Oil Compa | | Oil Operator | Jun 1995 |
| 18280 | Marmik Oil Company | El Dorado, AR 71730 | Oil & Gas Operator | Jan 2015 |
| 18281 | Maroon Energy LLC | Spring, TX 77379 | Oil & Gas Operator | Feb 2025 |
| 18282 | Maroski, Inc. | | Oil Operator | Jan 1989 |
| 18283 | Marple Petroleum LLC | Edmond, OK 73013 | Oil Operator | Aug 2025 |
| 18284 | Marquee Corporation | Houston, TX 77024 | Oil & Gas Operator | Dec 2025 |
| 18285 | Marquis Resources, LLC | | Oil & Gas Operator | Jul 2021 |
| 18286 | Marquis-Allred Eng Inc | | Oil & Gas Operator | Apr 1992 |
| 18287 | Marquise Oil Properties Inc | Konawa, OK 74849 | Oil & Gas Operator | Nov 1992 |
| 18288 | Marr Company | | Oil & Gas Operator | Mar 1989 |
| 18289 | Marr, M. H. | Dallas, TX 75201 | Gas Operator | Jan 2002 |
| 18290 | Marrow, N. S. | Austin, TX 78703 | Oil & Gas Operator | Aug 2012 |
| 18291 | Marrs Bros Oil Co Inc | Drumright, OK 74030 | Oil Operator | Sep 1994 |
| 18292 | Marrs, Richard L.(Deceased) | Arkansas City, KS 67005 | Oil & Gas Operator | Feb 2013 |
| 18293 | Marsh Engineering, Inc. | | Oil & Gas Operator | Dec 1990 |
| 18294 | Marsh Lonnie C | Konawa, OK 74849 | Oil & Gas Operator | Aug 2025 |
| 18295 | Marsh Oil & Gas Company | Oklahoma City, OK 73118 | Oil & Gas Operator | Aug 2025 |
| 18296 | Marsh Oil & Gas Field Services, Inc | Sebree, KY 42455 | Oil & Gas Operator | Dec 2023 |
| 18297 | Marsh Operating Company | Dallas, TX 75221 | Oil & Gas Operator | Jun 2025 |
| 18298 | Marsha Azar | | Oil & Gas Operator | Jan 2017 |
| 18299 | Marshall & McCain | | Oil & Gas Operator | Oct 1988 |
| 18300 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2025 |