| 1001 | McGinnis Oil | | Oil & Gas Operator | Dec 2002 |
| 1002 | McGoldrick & Watson | | Oil & Gas Operator | Jul 1987 |
| 1003 | McGoldrick & Watson - Alagood | | Oil Operator | Oct 1995 |
| 1004 | McGoldrick & Watson DRLG., Co. | | Oil & Gas Operator | Jul 1987 |
| 1005 | McGoldrick & Watson, Et Al | | Oil Operator | Jul 1987 |
| 1006 | McGoldrick & Watson-Walker | | Oil Operator | Jul 1987 |
| 1007 | McGoldrick Oil Company | Shreveport, LA 71129 | Oil & Gas Operator | Jul 2020 |
| 1008 | McGonagill J W | MT Gilead, OH 43338 | Oil Operator | Dec 1984 |
| 1009 | McGonigal Dan L | Skiatook, OK 74070 | Oil & Gas Operator | Sep 2024 |
| 1010 | McGonigal Donald T | Tulsa, OK 74114-2145 | Oil & Gas Operator | Jul 2004 |
| 1011 | McGonigal Ted W | Norman, OK 73072 | Oil & Gas Operator | Mar 2025 |
| 1012 | McGowan Working Partners | Jackson, MS 39296 | Oil & Gas Operator | Dec 2000 |
| 1013 | McGowan Working Partners, Inc. | Jackson, MS 39296 | Oil & Gas Operator | Sep 2025 |
| 1014 | McGowen Resources Co., Inc. | Dallas, TX 75206 | Oil & Gas Operator | Aug 2003 |
| 1015 | McGown Drilling | | Oil Operator | Apr 1993 |
| 1016 | McGown Drilling, Inc. | Mound City, KS 66056 | Oil Operator | Apr 2025 |
| 1017 | McGrath, Rollie | Lake City, KS 67071 | Gas Operator | Apr 2025 |
| 1018 | McGriff Craig Exploration Inc | Oklahoma City, OK 73172-0364 | Oil & Gas Operator | Mar 2023 |
| 1019 | McGuffin, Joe Jr. | Christoval, TX 76935 | Oil & Gas Operator | Sep 2025 |
| 1020 | McGuffin, Joe S. Inc. | Mathis, TX 78368 | Gas Operator | Sep 2025 |
| 1021 | McGuire Brothers | Phoenix, AZ 85045 | Oil & Gas Operator | Sep 2025 |
| 1022 | McGuire John C | Gillette, WY 82717 | Oil & Gas Operator | Oct 2005 |
| 1023 | McGuire Tom Oil Company | Depew, OK 74028 | Oil Operator | Apr 2011 |
| 1024 | McIlhenny-Powell Operating Co | | Gas Operator | Aug 1983 |
| 1025 | McIlvain Oil LLC | Madison, KS 66860 | Oil Operator | Dec 2017 |
| 1026 | McIntosh Oil & Gas, Inc. | Coalton, WV 26257 | Oil & Gas Operator | Dec 2021 |
| 1027 | McIntyre M L | Oklahoma City, OK 73154-0523 | Oil & Gas Operator | Jul 1996 |
| 1028 | McIntyre Oil Company | | Oil & Gas Operator | Jan 1992 |
| 1029 | McIver, Inc | San Angelo, TX 76903 | Oil & Gas Operator | Sep 2025 |
| 1030 | McIver, Terry L. | Santa Anna, TX 76878 | Oil & Gas Operator | Aug 2003 |
| 1031 | McKay Oil | Portales, NM 88130 | Oil & Gas Operator | Apr 1996 |
| 1032 | McKay Oil & Gas LLC | Albuquerque, NM 87191 | Gas Operator | Mar 2020 |
| 1033 | McKay Oil Company | Perry, OK 73077 | Oil Operator | Nov 2008 |
| 1034 | McKay Oil Corp | Roswell, NM 88202 | Oil & Gas Operator | Aug 2017 |
| 1035 | McKay Operating LLC | Lubbock, TX 79416 | Oil & Gas Operator | Oct 2023 |
| 1036 | McKean Bros. | | Oil & Gas Operator | Dec 1997 |
| 1037 | McKee Don Drill Co Inc | Newark, OH 43058 | Oil & Gas Operator | Dec 2012 |
| 1038 | McKee Energy Comapny Inc | | Oil & Gas Operator | Apr 2011 |
| 1039 | McKee, Kenneth W. Oil Co. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 1040 | McKeever, Tyra, Swenson Venture | Stamford, TX 79553 | Oil & Gas Operator | Apr 1996 |
| 1041 | McKellpee Energy Corp. | Olean, NY 14760 | Oil & Gas Operator | Dec 2024 |
| 1042 | McKelvy A D Oil | | Gas Operator | Feb 1995 |
| 1043 | McKenna Oil Co | Kane, PA 16735-9711 | Oil & Gas Operator | Dec 2004 |
| 1044 | McKenney & Chambers Oil Company | Westbrook, TX 79565 | Oil & Gas Operator | Oct 2003 |
| 1045 | McKenzie & Assoc. | | Gas Operator | Dec 1990 |
| 1046 | McKenzie Management Inc. | | Oil & Gas Operator | Aug 1989 |
| 1047 | McKenzie Methane | Houston, TX BAD ADDR | Gas Operator | Apr 1994 |
| 1048 | McKenzie Operating Company, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2011 |
| 1049 | McKenzie Petroleum Company | Houston, TX 77063 | Oil & Gas Operator | Aug 1995 |
| 1050 | McKenzie Production Company | Houston, TX 77063 | Oil & Gas Operator | May 1995 |
| 1051 | McKinney Kenneth R | Okmulgee, OK 74447-6932 | Oil Operator | Aug 2000 |
| 1052 | McKinney Operating Company | Canadian, TX 79014 | Gas Operator | May 2002 |
| 1053 | McKinney, Jason G. | | Oil Operator | Dec 2021 |
| 1054 | McKinney, M. H. | Midland, TX 79701 | Oil & Gas Operator | Apr 1995 |
| 1055 | McKnight, C. L. | McLeod, TX 75565 | Oil & Gas Operator | Sep 2025 |
| 1056 | McKnight, C. L. Oil Co. LLP | McLeod, TX 75565 | Oil & Gas Operator | Sep 2025 |
| 1057 | McKnight, J. C. | Jefferson, TX 75657 | Oil & Gas Operator | Nov 2019 |
| 1058 | MCL 1 Oil & Gas Wyoming LLC | Minneapolis, MN 55402 | Oil & Gas Operator | Jul 2018 |
| 1059 | McLain Exploration, Inc. | Boerne, TX 78006 | Oil & Gas Operator | Mar 2008 |
| 1060 | McLain J. Forman | | Oil & Gas Operator | Mar 1988 |
| 1061 | McLane Trust* Dixie | | Gas Operator | Jun 2025 |
| 1062 | McLaurin Oil Co. | | Oil Operator | Jan 2025 |
| 1063 | McLelland Engineering & MGMT. | Houston, TX 77042 | Oil & Gas Operator | Mar 1999 |
| 1064 | McLemore, Laurence | Iowa Park, TX 76367 | Oil & Gas Operator | Sep 2025 |
| 1065 | McLennan Family Properties LLP | | Oil & Gas Operator | Dec 2021 |
| 1066 | McLeod Gas Gath & Proc Co. L.L.C. | | Oil Operator | Jul 2012 |
| 1067 | McLeod, George L. Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2002 |
| 1068 | McLester Oil & G | | Oil & Gas Operator | Jun 1992 |
| 1069 | McLish & Luff | Denver, CO 80202 | Gas Operator | Nov 1972 |
| 1070 | McLish, Holmes P | Denver, CO 80202 | Oil & Gas Operator | Dec 1983 |
| 1071 | McLouth Operating Company, Inc. | Kansas City, MO 64106 | Oil Operator | Aug 1999 |
| 1072 | MCM Energy Inc | Edmond, OK 73013-8035 | Oil & Gas Operator | Nov 2021 |
| 1073 | MCM Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 1074 | McMahon Operating Co., L.C. | Pampa, TX 79066 | Oil & Gas Operator | Dec 2004 |
| 1075 | McMahon-Bullington Drilling Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Mar 1996 |
| 1076 | McMahon-Bullington LP | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2009 |
| 1077 | McMillan, David | FT. Worth, TX 76107 | Oil Operator | Aug 2001 |
| 1078 | McMillan, L.L.C. | Sedan, KS 67361 | Oil Operator | Dec 2019 |
| 1079 | McMillen, Clay Eugene (Gene) | Chanute, KS 66720 | Oil Operator | Aug 1997 |
| 1080 | McMillin C C & Company Inc | Guthrie, OK 73044 | Oil & Gas Operator | May 2025 |
| 1081 | McMinn Operating Company, Inc. | Hempstead, TX 77445 | Oil & Gas Operator | Sep 2025 |
| 1082 | McMoran Exploration Company | | Oil & Gas Operator | May 1985 |
| 1083 | McMoran Oil & Gas LLC | New Orleans, LA 70160 | Oil & Gas Operator | Oct 2021 |
| 1084 | McMoran Production Co. | | Oil & Gas Operator | May 1985 |
| 1085 | McMoran-Transco | | Oil & Gas Operator | Aug 1979 |
| 1086 | McMullan Oil Company | San Antonio, TX 78212 | Oil & Gas Operator | Jun 2023 |
| 1087 | McMullin Well Se | | Oil & Gas Operator | Sep 1995 |
| 1088 | McMullin, Douglas | Wellsville, KS 66092 | Oil Operator | Nov 2024 |
| 1089 | McMurrey, R. J., Production Comp | Tyler, TX 75711 | Oil & Gas Operator | Sep 2025 |
| 1090 | McMurry Energy Company | | Oil & Gas Operator | Dec 2001 |
| 1091 | McMurry Oil LLC | Denver, CO 80202 | Oil & Gas Operator | Dec 2004 |
| 1092 | McMurtrie Oil Inc | | Oil & Gas Operator | Feb 2025 |
| 1093 | McNallen & Griffin | Keller, TX 76244 | Oil & Gas Operator | Sep 2025 |
| 1094 | McNallen Oil Co., Inc. | Keller, TX 76244 | Oil & Gas Operator | Sep 2025 |
| 1095 | McNeal Production Inc | Perry, OK 73077-0268 | Oil & Gas Operator | Nov 2014 |
| 1096 | McNeill Randy & W R | Okmulgee, OK 74447 | Oil & Gas Operator | Nov 2013 |
| 1097 | McNeish Oil Oper | | Oil & Gas Operator | Feb 1991 |
| 1098 | McNeish Oil Operations | | Oil Operator | Nov 2019 |
| 1099 | McNic Oil & Gas Midcontinent | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | May 2024 |
| 1100 | McNic Oil & Gas Midcontinent,Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 1999 |