| 1001 | Lock Arbor Production Co | | Gas Operator | Aug 1987 |
| 1002 | Lockard Petroleum, Inc. | Hamilton, KS 66853 | Oil Operator | Feb 2025 |
| 1003 | Locke Stock & Barrel Res Inc | Calgary, AB T2P3G | Oil Operator | Nov 1998 |
| 1004 | Locke-Taylor Drilling Co | Rifle, CO 81650 | Gas Operator | Mar 2006 |
| 1005 | Lockhart Oil LLC | Neosho Falls, KS 66758 | Oil Operator | Feb 2025 |
| 1006 | Lockout Corporation | Austin, TX 78746 | Oil & Gas Operator | Jun 2025 |
| 1007 | Lockridge, John P | Denver, CO 80202 | Gas Operator | Mar 1999 |
| 1008 | Loco | Casper, WY 82602 | Oil & Gas Operator | Jul 2022 |
| 1009 | Loco Oil Company | Loco, OK 73442 | Oil Operator | Feb 1993 |
| 1010 | Locust Ridge Gas Company | | Oil Operator | Mar 2003 |
| 1011 | Lode Holdings, LLC | Wichita Falls, TX 76301 | Oil Operator | Jun 2025 |
| 1012 | Lodel Energy Resources Corporation | Austin, TX 78703 | Oil Operator | Jun 2025 |
| 1013 | Lodestone Operating | Portland, TX 78374 | Oil & Gas Operator | Mar 2025 |
| 1014 | Lodestone Operating, Inc. | Portland, TX 78374 | Oil & Gas Operator | Jun 2025 |
| 1015 | Lodi Drilling & Service Co. | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Jun 2025 |
| 1016 | Lodi Gas Storage L.L.C. | | Gas Operator | Apr 2025 |
| 1017 | Lodi Operating Company LLC | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Jun 2025 |
| 1018 | Loe Oil & Gas Corporation | | Gas Operator | Dec 1977 |
| 1019 | Loe Petroleum & Environmental Engineering LLC | | Oil Operator | Mar 2025 |
| 1020 | Loe Pipe Yard, Inc. | | Oil & Gas Operator | Jan 1997 |
| 1021 | Loeb Bros., LLC | Lawrenceville, IL 62439 | Oil Operator | Dec 2016 |
| 1022 | Loeb Herman L | | Oil & Gas Operator | Jan 1996 |
| 1023 | Loeb LLC* Herman L | | Oil & Gas Operator | Apr 2025 |
| 1024 | Loeb, Herman L, LLC | Lawrenceville, IL 62439 | Oil Operator | Dec 2017 |
| 1025 | Loewen E K | | Oil Operator | Mar 1986 |
| 1026 | Loewen Operator | | Oil & Gas Operator | Mar 1995 |
| 1027 | Loewen Operator, Inc. | Canton, KS 67428 | Oil & Gas Operator | Feb 2025 |
| 1028 | Loftis Bobby Lee Rev Trust | Holdenville, OK 74848 | Oil & Gas Operator | Jun 2022 |
| 1029 | Lofton, W. A. | Wichita Falls, TX 76301 | Oil & Gas Operator | Jun 1998 |
| 1030 | Log Energy | MT Gilead, OH 43338 | Oil Operator | Dec 2024 |
| 1031 | Log Operating, LLC | Eagle Pass, TX 78853 | Oil & Gas Operator | Jun 2025 |
| 1032 | Logan Clay Prod Company | Logan, OH 43138 | Oil & Gas Operator | Dec 2005 |
| 1033 | Logan Energy Co. | Cross Plains, TX 76443 | Oil & Gas Operator | Nov 1997 |
| 1034 | Logan Oil, LLC | | Oil & Gas Operator | May 2010 |
| 1035 | Logan Productions LLC | Wewoka, OK 74884 | Oil Operator | Feb 2025 |
| 1036 | Logas Energy, LLC | Lafayette, LA 70508 | Oil & Gas Operator | Jun 2025 |
| 1037 | Logos Operating LLC | Farmington, NM 87401 | Oil & Gas Operator | Mar 2025 |
| 1038 | Logsdon Richard | | Oil Operator | Mar 1988 |
| 1039 | Logue And Patterson, Inc. | | Oil & Gas Operator | Nov 1991 |
| 1040 | Loil Oil LLC | Golden, CO 80402 | Oil & Gas Operator | Apr 2025 |
| 1041 | Loin Energy Corporation | La Grange, TX 78945 | Oil & Gas Operator | Jun 2025 |
| 1042 | Loki Oil LLC | Cushing, OK 74023 | Oil & Gas Operator | Nov 2024 |
| 1043 | Lola Energy Petroco LLC | Canonsburg, PA 15317 | Gas Operator | Mar 2025 |
| 1044 | Lolocav, LLC | Sonora, TX 76950 | Oil & Gas Operator | Jun 2025 |
| 1045 | Loma Enterprises Inc | Cortland, OH 44410 | Oil & Gas Operator | Dec 1998 |
| 1046 | Loma Oil Company | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2014 |
| 1047 | Loma VIsta Farms | Floresville, TX 78114 | Oil & Gas Operator | Jun 2019 |
| 1048 | Lomak Petroleum Michigan Inc | | Gas Operator | Jul 1992 |
| 1049 | Lomak Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 1998 |
| 1050 | Loman Linda Gann | Norman, OK 73069-6548 | Oil Operator | Apr 2011 |
| 1051 | Lomax Exploration Company | Roosevelt, UT 84066 | Oil & Gas Operator | Jun 1995 |
| 1052 | Lomax Operating Company, Inc. | Abilene, TX 79602 | Oil & Gas Operator | Jun 2011 |
| 1053 | London Petroleum Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2025 |
| 1054 | London William W | Oklahoma City, OK 73116 | Oil & Gas Operator | Nov 2015 |
| 1055 | London William W Inc | Oklahoma City, OK 73116-5116 | Oil & Gas Operator | Apr 2016 |
| 1056 | Lone Eagle LLC | | Oil & Gas Operator | Dec 2003 |
| 1057 | Lone Jack Oil Co. | | Oil Operator | Feb 2025 |
| 1058 | Lone Mountain Prod | | Oil Operator | Dec 2018 |
| 1059 | Lone Mountain Production Company | | Oil & Gas Operator | Jan 2016 |
| 1060 | Lone MTN Production Co | Billings, MT 59108-0965 | Oil & Gas Operator | Jul 2019 |
| 1061 | Lone Oak Energy Inc | Kyle, TX 78640 | Oil & Gas Operator | Jun 2025 |
| 1062 | Lone Pine Operating Company, Inc. | Salem, WV 26426 | Oil & Gas Operator | Dec 2021 |
| 1063 | Lone Pine Production Assoc.,Inc. | Houston, TX 77056 | Oil & Gas Operator | Apr 1993 |
| 1064 | Lone Star Gas Co. | Dallas, TX 75201 | Oil & Gas Operator | Jul 1999 |
| 1065 | Lone Star Interests, Inc. | Chanute, KS 66720 | Oil Operator | Sep 2001 |
| 1066 | Lone Star Land And Energy II LLC | Dallas, TX 75214 | Oil & Gas Operator | Jan 2020 |
| 1067 | Lone Star Oil & Gas | Midland, TX 79702 | Oil & Gas Operator | Jun 2025 |
| 1068 | Lone Star Oil & Gas, Inc | Greenville, KY 42345 | Oil & Gas Operator | Dec 2023 |
| 1069 | Lone Star Oil Co. | Jacksboro, TX 76458 | Oil & Gas Operator | Feb 2025 |
| 1070 | Lone Star Operating Company | Pearsall, TX 78061 | Oil & Gas Operator | Jun 2025 |
| 1071 | Lone Star Operations LLC | Lubbock, TX 79401 | Oil & Gas Operator | Jun 2025 |
| 1072 | Lone Star Pipeline Company | Dallas, TX 75201 | Oil & Gas Operator | Jul 1999 |
| 1073 | Lone Star Production | Lawn, TX 79530 | Oil & Gas Operator | Jun 2025 |
| 1074 | Lone Star Resources Company | Keyes, OK 73947 | Oil & Gas Operator | Mar 2015 |
| 1075 | Lone Star Services | Pecos, TX 79772 | Oil & Gas Operator | Jun 2025 |
| 1076 | Lone Tree Oil & Gas LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Jun 2025 |
| 1077 | Lone Wolf Oil & Gas Co., LLC | Moline, KS 67353 | Oil & Gas Operator | Feb 2025 |
| 1078 | Lone Wolf Oil LLC | Wellsville, KS 66092 | Oil Operator | Dec 2009 |
| 1079 | Lone Wolf Operating Company | Denver, CO 80202 | Oil & Gas Operator | Nov 2005 |
| 1080 | Lone Wolf Operating Company, LP | Haxtun, CO 80731 | Oil & Gas Operator | Sep 2009 |
| 1081 | Lone Wolf Operating, LLC | Billings, MT 59108 | Oil & Gas Operator | Feb 2025 |
| 1082 | Lonesome B, LLC | Monahans, TX 79756 | Oil & Gas Operator | Jun 2025 |
| 1083 | Lonestar Foundation Inc. | | Oil Operator | Dec 2008 |
| 1084 | Lonestar Operating, LLC | Houston, TX 77084 | Oil & Gas Operator | Nov 2022 |
| 1085 | Lonestar Petroleum Services, LLC | Artesia, NM 88210 | Oil Operator | Mar 2025 |
| 1086 | Lonestar Production Services | Graham, TX 76450 | Oil Operator | Jun 2025 |
| 1087 | Long Acres Prod. Co., Inc. | | Oil & Gas Operator | Aug 1986 |
| 1088 | Long And Ware Oil, A General Partnership | Pawhuska, OK 74056 | Oil Operator | Jan 2021 |
| 1089 | Long Beach Oil Development Co | Glendale, CA 91203 | Oil & Gas Operator | Jun 2004 |
| 1090 | Long Branch Production, LLC | Buna, TX 77612 | Gas Operator | Sep 2024 |
| 1091 | Long Bros. Oil Co. | | Oil Operator | Jul 2015 |
| 1092 | Long Drilling Company, LLC | Hamilton, KS 66853 | Oil Operator | Jan 2025 |
| 1093 | Long Engineering Company Inc | Oklahoma City, OK 73112-7769 | Oil Operator | Jun 2008 |
| 1094 | Long George L | San Antonio, TX 78209 | Oil & Gas Operator | Feb 1996 |
| 1095 | Long Jack Senior | | Oil Operator | Jan 2004 |
| 1096 | Long Oil & Natural Gas Corp. | | Oil & Gas Operator | Feb 1996 |
| 1097 | Long Oil And Gas Expl., LTD | | Oil & Gas Operator | Apr 1988 |
| 1098 | Long Operating, L.L.C. | Shreveport, LA 71166 | Oil & Gas Operator | Jun 2006 |
| 1099 | Long Petroleum, Inc. | Shreveport, LA 71166 | Oil & Gas Operator | Jun 2020 |
| 1100 | Long Production LLC | Claremore, OK 74017-2808 | Oil & Gas Operator | Oct 2019 |