| 1001 | Petrohawk Energy Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2005 |
| 1002 | Petrohawk Operating Company | Houston, TX 77056 | Oil & Gas Operator | Oct 2021 |
| 1003 | Petrojen Production Company Inc | Bakersfield, CA 93311 | Oil Operator | Apr 2025 |
| 1004 | Petrol Industries, Inc. | Shreveport, LA 71137 | Oil & Gas Operator | Jun 2012 |
| 1005 | Petrol Oil & Gas, Inc. | Overland Park, KS 66210 | Oil & Gas Operator | Dec 2008 |
| 1006 | Petrolanic Inc | Tulsa, OK 74105 | Oil Operator | Oct 1991 |
| 1007 | Petrolegacy Energy II, LLC | Denver, CO 80202 | Oil & Gas Operator | Jun 2023 |
| 1008 | Petrolero Corp. | San Antonio, TX 78205 | Oil & Gas Operator | Feb 1998 |
| 1009 | Petrolero, LLC | Plano, TX 75026 | Oil & Gas Operator | Jul 2025 |
| 1010 | Petroleum Advisors Int'L., Inc. | Houston, TX 77224 | Gas Operator | Jun 2005 |
| 1011 | Petroleum Capital, L.C. | Dallas, TX 75367 | Oil & Gas Operator | Jul 2025 |
| 1012 | Petroleum Corp Of Delaware The | | Oil & Gas Operator | May 1991 |
| 1013 | Petroleum Corpor | | Oil Operator | Jan 1983 |
| 1014 | Petroleum Corporation Of Texas | Breckenridge, TX 76024 | Oil & Gas Operator | May 2002 |
| 1015 | Petroleum Develo | | Oil Operator | Sep 1986 |
| 1016 | Petroleum Development Company | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 1017 | Petroleum Development Cor | Bridgeport, WV 26330 | Oil & Gas Operator | Dec 2004 |
| 1018 | Petroleum Development Corporation | Denver, CO 80202 | Oil & Gas Operator | Dec 2017 |
| 1019 | Petroleum Development LLC | | Oil Operator | Jul 2018 |
| 1020 | Petroleum Energy | | Oil & Gas Operator | Mar 1991 |
| 1021 | Petroleum Energy Corp | | Oil & Gas Operator | Aug 2012 |
| 1022 | Petroleum Energy, Inc. | Wichita, KS 67202 | Oil Operator | May 1999 |
| 1023 | Petroleum Engineering & Management Corp. | Casper, WY 82609 | Oil & Gas Operator | Jul 2018 |
| 1024 | Petroleum Engineers, Inc. | | Oil & Gas Operator | Jun 1983 |
| 1025 | Petroleum Enterp | | Oil & Gas Operator | Sep 1995 |
| 1026 | Petroleum Enterprises, Inc. | Hutchinson, KS 67504 | Oil & Gas Operator | May 2001 |
| 1027 | Petroleum Exchange | | Oil & Gas Operator | Oct 1997 |
| 1028 | Petroleum Explo Prod Inc | Oilton, OK 74052 | Oil & Gas Operator | Jan 2017 |
| 1029 | Petroleum Explor | | Oil Operator | Aug 1983 |
| 1030 | Petroleum Exploration Company LTD Dba Petex | | Oil Operator | May 2025 |
| 1031 | Petroleum Exploration Company LTD LP | Breckenridge, TX 76424 | Oil & Gas Operator | May 2025 |
| 1032 | Petroleum Exploration Company LTD., Limited P | Breckenridge, TX 76424 | Oil & Gas Operator | May 2025 |
| 1033 | Petroleum Futures-Chapman Oil | | Oil & Gas Operator | Jul 1981 |
| 1034 | Petroleum Inc | Wichita, KS 67202 | Oil & Gas Operator | Oct 2021 |
| 1035 | Petroleum Incorp | | Oil & Gas Operator | Apr 1993 |
| 1036 | Petroleum International, Inc. | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2000 |
| 1037 | Petroleum Investment Inc | Oklahoma City, OK 73118 | Oil & Gas Operator | Nov 1998 |
| 1038 | Petroleum Investments, Inc | Shreveport, LA 71101 | Oil & Gas Operator | Dec 1977 |
| 1039 | Petroleum Land Company | Abilene, TX 79606 | Oil & Gas Operator | May 2000 |
| 1040 | Petroleum Manage | | Oil & Gas Operator | Oct 1994 |
| 1041 | Petroleum Management Int'L, Inc. | Sugar Land, TX 77487 | Oil & Gas Operator | Oct 1993 |
| 1042 | Petroleum Management LLC | Platteville, CO 80651 | Oil & Gas Operator | May 2011 |
| 1043 | Petroleum Management Prof Inc | Oklahoma City, OK 73120-1848 | Oil & Gas Operator | Apr 2009 |
| 1044 | Petroleum Management, Inc. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 2025 |
| 1045 | Petroleum Prod. MGMT | | Oil Operator | Nov 1995 |
| 1046 | Petroleum Produc | | Oil & Gas Operator | Dec 1996 |
| 1047 | Petroleum Production Corporation | Rantoul, KS 66079 | Oil Operator | Feb 2024 |
| 1048 | Petroleum Production Engineering | Fulton, TX 78358 | Oil Operator | Feb 2019 |
| 1049 | Petroleum Production Management, Inc. | Shawnee Mission, KS 66202 | Oil & Gas Operator | Nov 2021 |
| 1050 | Petroleum Production MGMT., Inc. | Kansas City, MO 64112 | Oil & Gas Operator | Jul 2025 |
| 1051 | Petroleum Products Inc | | Oil Operator | Jun 1996 |
| 1052 | Petroleum Proper | | Oil & Gas Operator | Nov 1995 |
| 1053 | Petroleum Properties Co Inc | Tulsa, OK 74132-4010 | Oil & Gas Operator | Sep 2012 |
| 1054 | Petroleum Properties MGMT Co LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Aug 2005 |
| 1055 | Petroleum Properties MGMT Corp | | Oil & Gas Operator | Aug 1990 |
| 1056 | Petroleum Properties MGMT. Co. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2014 |
| 1057 | Petroleum Property MGMT, Inc (A) | Fort Worth, TX 76101 | Oil & Gas Operator | May 1994 |
| 1058 | Petroleum Property Services, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Mar 2025 |
| 1059 | Petroleum Recovery & Expl Inc. | | Oil Operator | Oct 1984 |
| 1060 | Petroleum Recovery Systems, L.C. | Houston, TX 77024 | Oil Operator | Jul 2025 |
| 1061 | Petroleum Reserve Corporation | Plymouth MTNG, PA 19462 | Oil & Gas Operator | May 2008 |
| 1062 | Petroleum Resource Management Co | Fort Worth, TX 76107 | Oil & Gas Operator | Jan 2024 |
| 1063 | Petroleum Resource Management Corp | Denver, CO 80203 | Oil & Gas Operator | Jun 2025 |
| 1064 | Petroleum Resource MGMT Co TX | | Oil & Gas Operator | Sep 2020 |
| 1065 | Petroleum Resources Co | Wichita, KS 67206 | Oil & Gas Operator | May 2000 |
| 1066 | Petroleum Resources MGMT Corp. | | Oil & Gas Operator | Mar 2002 |
| 1067 | Petroleum Resources, LLC | | Oil & Gas Operator | Dec 2021 |
| 1068 | Petroleum Service Partners, Inc. | Indiana, PA 15701-0000 | Oil & Gas Operator | Dec 2021 |
| 1069 | Petroleum Technical Services Co. | Midland, TX 79707 | Oil & Gas Operator | Dec 2004 |
| 1070 | Petroleum Techno | | Oil & Gas Operator | Dec 1996 |
| 1071 | Petroleum Technologies, Inc. | Kansas City, MO 64112 | Oil & Gas Operator | Mar 2025 |
| 1072 | Petroleum Venture Capitol Corp | | Oil Operator | Jun 1980 |
| 1073 | Petrolia Drilling Corporation | | Oil & Gas Operator | Jul 2003 |
| 1074 | Petrolia Energy Corporation | Pearland, TX 77581 | Oil Operator | Jan 2024 |
| 1075 | Petrolia Group, L.L.C. | Katy, TX 77449 | Oil & Gas Operator | Jul 2025 |
| 1076 | Petromac, Inc. | Onalaska, TX 77360 | Oil & Gas Operator | Jul 2025 |
| 1077 | Petromark Energy LLC | Oklahoma City, OK 73116-7634 | Oil & Gas Operator | Jun 2000 |
| 1078 | Petromark Resources Company | Tulsa, OK 74136 | Oil & Gas Operator | Sep 1993 |
| 1079 | Petromax Oil And Gas Inc | | Oil & Gas Operator | Dec 1988 |
| 1080 | Petromerica Operating LLC | Oklahoma City, OK 73102-4613 | Oil Operator | Apr 2025 |
| 1081 | Petrominerals Corp. | | Oil & Gas Operator | Dec 2003 |
| 1082 | Petromining, Inc. | Plano, TX 75026 | Oil & Gas Operator | Jul 2025 |
| 1083 | Petron Development Company | | Oil & Gas Operator | Oct 2020 |
| 1084 | Petron Energy Inc | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 1085 | Petron Oil & Gas | Lenexa, KS 66215 | Oil & Gas Operator | Mar 2025 |
| 1086 | Petron Oil Company | Missouri City, TX 77489 | Oil & Gas Operator | Jul 2025 |
| 1087 | Petronomics Petroleum, Inc. | Austin, TX 78734 | Oil & Gas Operator | Jan 1995 |
| 1088 | Petronomics, Inc. | Houston, TX 77074 | Oil & Gas Operator | Aug 2003 |
| 1089 | Petronova, LLC | | Gas Operator | Jul 2014 |
| 1090 | Petroplex Energy Inc. | Midland, TX 79702 | Oil & Gas Operator | Jul 2025 |
| 1091 | Petroplex Equipment, Inc. | Midland, TX 79701 | Oil & Gas Operator | May 2019 |
| 1092 | Petropoint Energy Operating, LLC | Houston, TX 77098 | Oil & Gas Operator | Jul 2025 |
| 1093 | Petroprize | | Oil & Gas Operator | May 2025 |
| 1094 | Petropro Energy Partners, L.P. | Houston, TX 77024 | Oil & Gas Operator | Jan 2013 |
| 1095 | Petropro Petroleum LLC | | Oil Operator | Mar 2025 |
| 1096 | Petroquest Energy, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Feb 2001 |
| 1097 | Petroquest Energy, L.L.C. | Lafayette, LA 70505 | Oil & Gas Operator | Jul 2025 |
| 1098 | Petroquest Exploration, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Mar 2008 |
| 1099 | Petroquest Oil & Gas LLC | Wewoka, OK 74884 | Oil & Gas Operator | Apr 2025 |
| 1100 | Petroquest, LLC | El Dorado, AR 71730 | Oil & Gas Operator | Jan 2025 |