| 1001 | Apc Operating Partnership | Tulsa, OK 74136 | Oil & Gas Operator | Oct 1996 |
| 1002 | Apc Operating Partnership LP | Tulsa, OK 74136-4224 | Oil & Gas Operator | Jun 2015 |
| 1003 | Apco Oil Corp | Oklahoma City, OK 73116 | Oil & Gas Operator | Jun 1993 |
| 1004 | Apd Company | | Oil & Gas Operator | Apr 1987 |
| 1005 | Apex Crude Oil Co | Logan, OH 43138 | Oil & Gas Operator | Dec 1996 |
| 1006 | Apex DRLG | Bermuda Dunes, CA 92203 | Oil & Gas Operator | Dec 2019 |
| 1007 | Apex Energy (Pa) LLC | | Gas Operator | May 2025 |
| 1008 | Apex Energy, Inc. | Corpus Christ, TX 78413 | Oil & Gas Operator | Sep 2026 |
| 1009 | Apex Energy, L.L.C. | Tulsa, OK 74114 | Oil & Gas Operator | Feb 2026 |
| 1010 | Apex Minerals Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 1994 |
| 1011 | Apex Natural Gas, LLC | Houston, TX 77002 | Gas Operator | Sep 2026 |
| 1012 | Apex Oil & Gas, Inc. | Houston, TX 77067 | Oil & Gas Operator | Oct 2009 |
| 1013 | Apex Oil Ventures Inc | | Oil & Gas Operator | May 2026 |
| 1014 | Apex Operating & Equip. Co. | Bowie, TX 76230 | Oil & Gas Operator | Nov 2003 |
| 1015 | Apex Operating Partners, LLC | San Angelo, TX 76902 | Oil & Gas Operator | Sep 2026 |
| 1016 | Apex Production LTD. | Albany, TX 76430 | Oil Operator | Sep 2026 |
| 1017 | Apex Resources Inc | Allison Park, PA 15101-3838 | Oil & Gas Operator | Dec 1993 |
| 1018 | Apex Resources LLC | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2026 |
| 1019 | Apex Royalties, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 1997 |
| 1020 | Apexco, Inc. | Sand Springs, OK 74063 | Oil & Gas Operator | Jun 2026 |
| 1021 | Apexco-McCormick-Coastal | | Oil & Gas Operator | Dec 1977 |
| 1022 | Apexway Corp. | | Oil Operator | Dec 2024 |
| 1023 | API Operating Co. | Houston, TX 77036 | Oil & Gas Operator | Sep 2026 |
| 1024 | Apogee Oil & Gas LLC | Edmond, OK 73034 | Oil Operator | May 2026 |
| 1025 | Apollo Energies | Pratt, KS 67124 | Oil Operator | Aug 2016 |
| 1026 | Apollo Energies Inc | Pratt, KS 67124 | Oil & Gas Operator | Apr 2026 |
| 1027 | Apollo Energy Operating Co, LP | Lake Charles, LA 70601 | Oil & Gas Operator | Dec 2024 |
| 1028 | Apollo Energy Operating, LP | | Oil & Gas Operator | Mar 2011 |
| 1029 | Apollo Energy, L.L.C. | | Oil & Gas Operator | Jul 2018 |
| 1030 | Apollo Energy, L.P. | Lake Charles, LA 70601 | Oil Operator | May 2014 |
| 1031 | Apollo Exploration And Development Inc | | Oil & Gas Operator | Jun 2026 |
| 1032 | Apollo Gas Co | Pittsburgh, PA 15236-1435 | Gas Operator | Dec 1991 |
| 1033 | Apollo Petroleum Corporation | | Oil & Gas Operator | Dec 2012 |
| 1034 | Apollo Resources LLC | | Oil & Gas Operator | May 2026 |
| 1035 | App Energy, LLC | Monroe, MI 48161 | Oil & Gas Operator | Dec 2021 |
| 1036 | Appalachian Ener Tech Inc | Clearwater, FL 33518 | Oil & Gas Operator | Dec 2001 |
| 1037 | Appalachian Energy Inc | Pittsburgh, PA 15220 | Gas Operator | Dec 2008 |
| 1038 | Appalachian Expl Inc | Hartville, OH 44632 | Oil & Gas Operator | Dec 1989 |
| 1039 | Appalachian Exploration Corp | McMurray, PA 15317-3452 | Gas Operator | Dec 1995 |
| 1040 | Appalachian Petrol Corp | Girard, OH 44420 | Oil & Gas Operator | Dec 1989 |
| 1041 | Appalachian Resources Of Florida, LLC | Fort Myers, FL 33902 | Oil & Gas Operator | Dec 2024 |
| 1042 | Appaloosa Operating Company LLC | The Woodlands, TX 77387 | Oil & Gas Operator | Apr 2019 |
| 1043 | Apple Petroleum Corp | Mountainside, NJ 7092 | Oil Operator | Mar 2013 |
| 1044 | Appleton Oil Company | Chicago, IL 60657-4097 | Oil & Gas Operator | May 1993 |
| 1045 | Applied Mechanics Corp. | Bridgeport, WV 263304609 | Oil & Gas Operator | Dec 2021 |
| 1046 | Appling, J. B. | Midland, TX 79702 | Oil & Gas Operator | Jul 1997 |
| 1047 | Approach Operating LLC | Fort Worth, TX 76116 | Oil & Gas Operator | Sep 2020 |
| 1048 | Apr Operating LLC | Midland, TX 79701 | Oil & Gas Operator | Jun 2022 |
| 1049 | April Rain Prod. Co., Inc. | | Oil & Gas Operator | Jul 1992 |
| 1050 | Apv Caddo Pine LLC | | Oil & Gas Operator | Dec 2024 |
| 1051 | Apv McCamey LLC | MC Camey, TX 79752 | Oil & Gas Operator | Sep 2026 |
| 1052 | Apx & Assoc. | FT Stockton, TX 79735 | Oil & Gas Operator | Sep 1998 |
| 1053 | Apx Corporation | Houston, TX 77251 | Oil & Gas Operator | Dec 2009 |
| 1054 | Aqua-Oil Inc | Enid, OK 73703-6511 | Oil & Gas Operator | May 2019 |
| 1055 | Aquanyx Midstream LLC | Oklahoma City, OK 73131 | Oil Operator | Jun 2026 |
| 1056 | Aquila Energy Resources Corp. | Houston, TX 77042 | Oil & Gas Operator | Nov 2013 |
| 1057 | Aquila Resources | Burkesville, KY 42717 | Oil & Gas Operator | Dec 2022 |
| 1058 | Aquinas Oil & Gas, LLC | Muenster, TX 76252 | Oil Operator | Sep 2026 |
| 1059 | Arabella Operating, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2026 |
| 1060 | Arabella Petroleum Company, LLC | Austin, TX 78701 | Oil & Gas Operator | Sep 2026 |
| 1061 | Arabie, Inc. | Lake Charles, LA 70605 | Oil & Gas Operator | Apr 2025 |
| 1062 | Aracca Petroleum Company | | Oil Operator | May 1984 |
| 1063 | Aracca Petroleum Corporation | | Oil Operator | Dec 1987 |
| 1064 | Aralpa Corporation | | Oil & Gas Operator | May 1987 |
| 1065 | Araluen Energy, Inc. | Houston, TX 77094 | Oil Operator | Jun 2022 |
| 1066 | Aran Energy USA Inc. | | Oil & Gas Operator | Apr 1997 |
| 1067 | Aransas DRLG & Workover Co Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Jul 2019 |
| 1068 | Aransas Oil Company, Inc. | San Antonio, TX 78253 | Oil & Gas Operator | Jan 1999 |
| 1069 | Aransas Resources, Inc | Houston, TX 77083 | Oil & Gas Operator | Dec 2005 |
| 1070 | Aransas Resources, LP | Houston, TX 77006 | Oil & Gas Operator | Oct 2006 |
| 1071 | Arapaho Oil & Gas Inc | Roswell, NM 88202 | Oil & Gas Operator | Nov 1994 |
| 1072 | Arapaho Petroleum Inc | Englewood, CO 80155 | Oil & Gas Operator | Nov 1998 |
| 1073 | Arapaho Ventures Of Ny | Englewood, CO 80155 | Oil & Gas Operator | Dec 1990 |
| 1074 | Arapahoe Prod. Co. | Borger, TX 79008 | Oil & Gas Operator | May 2012 |
| 1075 | Arapahoe Resources LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Jun 2026 |
| 1076 | Arapahoe SPV LLC | | Oil & Gas Operator | Feb 2023 |
| 1077 | Aratex Production Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2003 |
| 1078 | Araxas Exploration, Inc. | The Woodlands, TX 77380 | Oil & Gas Operator | Apr 1998 |
| 1079 | Arb Energy Utah, LLC | Katy, TX 77494 | Oil & Gas Operator | Dec 2025 |
| 1080 | Arbco, Inc. | | Oil & Gas Operator | Jan 1996 |
| 1081 | Arben Oil, Inc. | Coleman, TX 76834 | Oil & Gas Operator | Sep 2026 |
| 1082 | Arbol Resources, Inc. | Houston, TX 77079 | Oil & Gas Operator | Sep 2026 |
| 1083 | Arbor Operating LLC | | Oil & Gas Operator | May 2026 |
| 1084 | Arbor Petroleum Corporation | Oklahoma City, OK 73102-4003 | Oil & Gas Operator | Mar 2011 |
| 1085 | Arbor Petroleum Inc | | Oil Operator | Jan 2003 |
| 1086 | Arbor Resources LLC | | Oil & Gas Operator | Dec 2007 |
| 1087 | Arbuckle Energy Inc. | Wichita, KS 67202 | Oil & Gas Operator | Jun 2025 |
| 1088 | Arbuckle Enterprises Inc | Edmond, OK 73083 | Oil & Gas Operator | May 2026 |
| 1089 | Arbuckle Service | Iola, KS 66749 | Oil Operator | Feb 1993 |
| 1090 | Arbuckle, A. Dale | Grenola, KS 67346 | Oil Operator | Sep 1990 |
| 1091 | Arbuckle, A. Dale & Kathryn E. Rev Trust | Grenola, KS 67346 | Oil & Gas Operator | May 2024 |
| 1092 | Arcadia Energy Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2026 |
| 1093 | Arcadia Expl. & Prod. Company | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2011 |
| 1094 | Arcadia Oil Company | Edmond, OK 73013-9009 | Oil & Gas Operator | Oct 2015 |
| 1095 | Arcadia Operating, LLC | Dallas, TX 75219 | Oil & Gas Operator | Sep 2026 |
| 1096 | Arcadia Refining Company | Tyler, TX 75701 | Oil & Gas Operator | Jan 1994 |
| 1097 | Arcadian Mineral Development | Brownwood, TX 76801 | Oil & Gas Operator | Dec 2013 |
| 1098 | Arcadian Mineral Development,LLC | Brownwood, TX 76801 | Oil & Gas Operator | Sep 2026 |
| 1099 | Arcadian Resources LLC | Glen Elder, KS 67446 | Oil & Gas Operator | Sep 2026 |
| 1100 | Arcady Oil Company | | Gas Operator | Dec 1989 |