| 18301 | McKay Oil Company | Perry, OK 73077 | Oil Operator | Nov 2008 |
| 18302 | McKay Oil Corp | Roswell, NM 88202 | Oil & Gas Operator | Aug 2017 |
| 18303 | McKay Operating LLC | Lubbock, TX 79416 | Oil & Gas Operator | Oct 2023 |
| 18304 | McKean Bros. | | Oil & Gas Operator | Dec 1997 |
| 18305 | McKee Don Drill Co Inc | Newark, OH 43058 | Oil & Gas Operator | Dec 2012 |
| 18306 | McKee Energy Comapny Inc | | Oil & Gas Operator | Apr 2011 |
| 18307 | McKee, Kenneth W. Oil Co. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 18308 | McKeever, Tyra, Swenson Venture | Stamford, TX 79553 | Oil & Gas Operator | Apr 1996 |
| 18309 | McKellpee Energy Corp. | Olean, NY 14760 | Oil & Gas Operator | Dec 2024 |
| 18310 | McKelvy A D Oil | | Gas Operator | Feb 1995 |
| 18311 | McKenna Oil Co | Kane, PA 16735-9711 | Oil & Gas Operator | Dec 2004 |
| 18312 | McKenney & Chambers Oil Company | Westbrook, TX 79565 | Oil & Gas Operator | Oct 2003 |
| 18313 | McKenzie Management Inc. | | Oil & Gas Operator | Aug 1989 |
| 18314 | McKenzie Methane | Houston, TX BAD ADDR | Gas Operator | Apr 1994 |
| 18315 | McKenzie Operating Company, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 18316 | McKenzie Petroleum Company | Houston, TX 77063 | Oil & Gas Operator | Aug 1995 |
| 18317 | McKenzie Production Company | Houston, TX 77063 | Oil & Gas Operator | May 1995 |
| 18318 | McKinney Kenneth R | Okmulgee, OK 74447-6932 | Oil Operator | Aug 2000 |
| 18319 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 18320 | McKinney, M. H. | Midland, TX 79701 | Oil & Gas Operator | Apr 1995 |
| 18321 | McKnight, C. L. | McLeod, TX 75565 | Oil & Gas Operator | Apr 2026 |
| 18322 | McKnight, C. L. Oil Co. LLP | McLeod, TX 75565 | Oil & Gas Operator | Apr 2026 |
| 18323 | McKnight, J. C. | Jefferson, TX 75657 | Oil & Gas Operator | Nov 2019 |
| 18324 | MCL 1 Oil & Gas Wyoming LLC | Minneapolis, MN 55402 | Oil & Gas Operator | Jul 2018 |
| 18325 | McLain Exploration, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Mar 2008 |
| 18326 | McLain J. Forman | | Oil & Gas Operator | Mar 1988 |
| 18327 | McLane Trust* Dixie | | Gas Operator | Oct 2025 |
| 18328 | McLaurin Oil Co. | | Oil Operator | Jan 2025 |
| 18329 | McLelland Engineering & MGMT. | Houston, TX 77042 | Oil & Gas Operator | Mar 1999 |
| 18330 | McLemore, Laurence | Iowa Park, TX 76367 | Oil & Gas Operator | Apr 2026 |
| 18331 | McLennan Family Properties LLP | | Oil & Gas Operator | Dec 2021 |
| 18332 | McLeod Gas Gath & Proc Co. L.L.C. | | Oil Operator | Jul 2012 |
| 18333 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 18334 | McLester Oil & G | | Oil & Gas Operator | Jun 1992 |
| 18335 | McLish, Holmes P | Denver, CO 80202 | Oil & Gas Operator | Dec 1983 |
| 18336 | McLouth Operating Company, Inc. | Kansas City, MO 64106 | Oil Operator | Aug 1999 |
| 18337 | MCM Energy Inc | Edmond, OK 73013-8035 | Oil & Gas Operator | Nov 2021 |
| 18338 | MCM Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Feb 2026 |
| 18339 | McMahon Operating Co., L.C. | Pampa, TX 79066 | Oil & Gas Operator | Dec 2004 |
| 18340 | McMahon-Bullington Drilling Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 1996 |
| 18341 | McMahon-Bullington LP | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2009 |
| 18342 | McMillan, David | FT. Worth, TX 76107 | Oil Operator | Aug 2001 |
| 18343 | McMillan, L.L.C. | Sedan, KS 67361 | Oil Operator | Dec 2019 |
| 18344 | McMillen, Clay Eugene (Gene) | Chanute, KS 66720 | Oil Operator | Aug 1997 |
| 18345 | McMillin C C & Company Inc | Guthrie, OK 73044 | Oil & Gas Operator | Jan 2026 |
| 18346 | McMinn Operating Company, Inc. | Hempstead, TX 77445 | Oil & Gas Operator | Apr 2026 |
| 18347 | McMoran Exploration Company | | Oil & Gas Operator | May 1985 |
| 18348 | McMoran Oil & Gas LLC | New Orleans, LA 70160 | Oil & Gas Operator | Oct 2021 |
| 18349 | McMoran Production Co. | | Oil & Gas Operator | May 1985 |
| 18350 | McMoran-Transco | | Oil & Gas Operator | Aug 1979 |
| 18351 | McMullan Oil Company | San Antonio, TX 78212 | Oil & Gas Operator | Jun 2023 |
| 18352 | McMullin Well Se | | Oil & Gas Operator | Sep 1995 |
| 18353 | McMullin, Douglas | Wellsville, KS 66092 | Oil Operator | Nov 2025 |
| 18354 | McMurrey, R. J., Production Comp | Tyler, TX 75711 | Oil & Gas Operator | Apr 2026 |
| 18355 | McMurry Energy Company | | Oil & Gas Operator | Dec 2001 |
| 18356 | McMurry Oil LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2004 |
| 18357 | McMurtrie Oil Inc | | Oil & Gas Operator | Jan 2026 |
| 18358 | McNallen & Griffin | Keller, TX 76244 | Oil & Gas Operator | Apr 2026 |
| 18359 | McNallen Oil Co., Inc. | Keller, TX 76244 | Oil & Gas Operator | Apr 2026 |
| 18360 | McNeal Production Inc | Perry, OK 73077-0268 | Oil & Gas Operator | Nov 2014 |
| 18361 | McNeill Randy & W R | Okmulgee, OK 74447 | Oil & Gas Operator | Nov 2013 |
| 18362 | McNeish Oil Oper | | Oil & Gas Operator | Feb 1991 |
| 18363 | McNeish Oil Operations | | Oil Operator | Nov 2019 |
| 18364 | McNic Oil & Gas Midcontinent | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | May 2024 |
| 18365 | McNic Oil & Gas Midcontinent,Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 1999 |
| 18366 | McNown, Carl H. | Moline, KS 67353 | Oil Operator | Jun 2021 |
| 18367 | McNutt P L | San Marcos, CA 92069-4817 | Oil & Gas Operator | Jul 1994 |
| 18368 | McO Resources Corporation | | Oil & Gas Operator | Feb 1986 |
| 18369 | McO Resources Integrated Corp | Houston, TX 77057 | Oil Operator | Jan 1997 |
| 18370 | McOil Montana One LLC | Vancouver, BC V6Z2W5 | Gas Operator | Aug 2025 |
| 18371 | McOil Operating Company LLC | Muskogee, OK 74401 | Oil & Gas Operator | Jan 2026 |
| 18372 | McOr Oil & Gas Corp | Houston, TX 77002 | Oil & Gas Operator | Oct 2013 |
| 18373 | McOr Oil Development, Inc. | | Oil & Gas Operator | Feb 1990 |
| 18374 | McOsker Bros., Inc. | San Antonio, TX 78264 | Oil & Gas Operator | Aug 2003 |
| 18375 | McPhearson, Richard E. | | Oil Operator | Mar 1956 |
| 18376 | McPherson Drilling | | Oil Operator | Jun 2015 |
| 18377 | McPherson Drilling Co. | | Oil Operator | Jan 1998 |
| 18378 | McQuadrangle, LC | Lubbock, TX 79424 | Oil & Gas Operator | Apr 2006 |
| 18379 | McQueen Ed & Company Inc | Lindsey, OK 73052 | Oil & Gas Operator | Apr 2014 |
| 18380 | McQueen Kevin L | Newark, OH 43055 | Oil Operator | Dec 2024 |
| 18381 | McQueeney, John J. | Osawatomie, KS 66064 | Oil Operator | Jan 1985 |
| 18382 | MCR Operating Group | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2026 |
| 18383 | MCR, LLC | Shelby, MT 59474 | Oil & Gas Operator | Dec 2025 |
| 18384 | McRae & Henry LTD | Golden, CO 80401 | Oil & Gas Operator | May 2022 |
| 18385 | McRae Exploration & Prod., Inc. | Houston, TX 77064 | Oil & Gas Operator | Feb 2017 |
| 18386 | McRae Exploration, Inc. | | Oil & Gas Operator | Mar 1984 |
| 18387 | McRae Exploration, Inc. & Epm | | Oil & Gas Operator | Mar 1978 |
| 18388 | McRae Exploration, Inc. & Herd | | Oil & Gas Operator | Mar 1984 |
| 18389 | McRae Exploration,Inc & Bec | | Oil & Gas Operator | Feb 1984 |
| 18390 | McRae Oil Corporation | | Oil & Gas Operator | Mar 1984 |
| 18391 | McRae, Nathan Rathburn | Hebbronville, TX 78361 | Oil & Gas Operator | Apr 1994 |
| 18392 | McRae, William R. | Scottsdale, AZ 85254 | Oil Operator | Aug 1995 |
| 18393 | McRain Petroleum | Weston, WV 26452-0000 | Oil & Gas Operator | Dec 2020 |
| 18394 | McShane, J. Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2004 |
| 18395 | McWhinney Holding Company LLLP | | Oil & Gas Operator | Mar 2021 |
| 18396 | MCZ Oil Co, Inc. | | Oil Operator | Feb 1994 |
| 18397 | MCZ, Inc. | Houston, TX 77026 | Oil & Gas Operator | Sep 1990 |
| 18398 | MD America Energy, LLC | Houston, TX 77224 | Oil & Gas Operator | Apr 2022 |
| 18399 | MDC Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Oct 2022 |
| 18400 | MDC Texas Operator LLC | Midland, TX 79705 | Oil & Gas Operator | Apr 2026 |