| 1 | C & C Minerals LTD | | Oil & Gas Operator | Dec 2019 |
| 2 | C & J Oil | | Oil & Gas Operator | Aug 2025 |
| 3 | C & M Oil Co. & Investments | | Oil & Gas Operator | Aug 2025 |
| 4 | C. C. Killingsworth Opr. | | Oil Operator | Dec 1999 |
| 5 | C. Case Company | | Oil & Gas Operator | Sep 2025 |
| 6 | C. E. Allen Co. Inc. | | Oil & Gas Operator | Sep 2025 |
| 7 | C. E. Braly | | Oil & Gas Operator | Dec 1991 |
| 8 | C. F. Sudduth | | Oil & Gas Operator | Dec 1988 |
| 9 | Caac 100 LLC | | Oil & Gas Operator | Sep 2025 |
| 10 | Caballero Operations LLC | | Oil & Gas Operator | Sep 2025 |
| 11 | Cal Continental Capital Inc. | | Oil Operator | Dec 2006 |
| 12 | Caleco LLC | | Oil & Gas Operator | Aug 2025 |
| 13 | California E.D.I. Inc. | | Oil & Gas Operator | Jan 2018 |
| 14 | California Hydrocarbons Corporation | | Gas Operator | Sep 2025 |
| 15 | California Oil Independents | | Oil & Gas Operator | Aug 2025 |
| 16 | California Petroleum Group Inc. | | Oil Operator | Aug 2025 |
| 17 | California Resources Elk Hills LLC | | Oil & Gas Operator | Sep 2025 |
| 18 | California Resources Long Beach Inc. | | Oil & Gas Operator | Sep 2025 |
| 19 | California Resources Production Corporation | | Oil & Gas Operator | Sep 2025 |
| 20 | California Southern Oil Co. | | Oil Operator | Dec 2000 |
| 21 | California/Nevada Developments LLC | | Oil Operator | Dec 2001 |
| 22 | Calnrg Operating LLC | | Oil & Gas Operator | Sep 2025 |
| 23 | Calresources LLC | | Oil & Gas Operator | Dec 1996 |
| 24 | Caltico Oil Corp. | | Oil Operator | Aug 2025 |
| 25 | Campbell Energy Corporation | | Oil & Gas Operator | May 1992 |
| 26 | Campo Verde Oil Inc. | | Oil Operator | Sep 2025 |
| 27 | Camtex Industries Inc. | | Oil Operator | Dec 1996 |
| 28 | Capco Resource Corporation | Orange,, CA 92869 | Oil Operator | Sep 2007 |
| 29 | Capital Production Company | | Oil Operator | Dec 1997 |
| 30 | Capitol Oil Corporation | | Oil & Gas Operator | Aug 2025 |
| 31 | Carbon California Operating Company LLC | | Oil & Gas Operator | Sep 2025 |
| 32 | Carl Weaver Properties | | Oil & Gas Operator | Dec 1987 |
| 33 | Carneros Energy Inc. | | Oil & Gas Operator | Dec 2004 |
| 34 | Carol Rhodabarger Heitz | | Oil & Gas Operator | Dec 1996 |
| 35 | Carson Dominguez Real Est Corp | | Oil & Gas Operator | Dec 1996 |
| 36 | Cascade Resources LLC | Edmond, OK 73083 | Oil & Gas Operator | Sep 2025 |
| 37 | Case'S Used Equipment | | Oil & Gas Operator | Sep 2025 |
| 38 | Casex Company | | Oil & Gas Operator | Dec 2007 |
| 39 | Castle Minerals | | Oil & Gas Operator | Dec 2018 |
| 40 | Cat Canyon Resources LLC | | Oil & Gas Operator | Aug 2025 |
| 41 | Cather Rogers Barnes & Cree | | Oil & Gas Operator | Dec 2009 |
| 42 | Cather, Barnes & Cree | | Oil & Gas Operator | Dec 2009 |
| 43 | Cather-Herley Oil Company | | Oil & Gas Operator | Sep 2025 |
| 44 | Cbase Corporation | | Oil & Gas Operator | Sep 2025 |
| 45 | Celeron Oil & Gas Company | | Oil & Gas Operator | Dec 1987 |
| 46 | Cemco-Edison No. 1 (F.R.) Partnership | | Oil & Gas Operator | Dec 2000 |
| 47 | Cen Cal Drilling Inc. | | Oil & Gas Operator | Dec 1994 |
| 48 | Cenex Inc. | | Oil & Gas Operator | Dec 1994 |
| 49 | Central California Oil Company | Fish Camp, CA 93623 | Oil & Gas Operator | Sep 2025 |
| 50 | Central Lease Inc. | | Oil & Gas Operator | Dec 1998 |
| 51 | Central Pacific Resources | | Oil Operator | Sep 2025 |
| 52 | Central Park Energy | | Oil & Gas Operator | Dec 1991 |
| 53 | Central Resources, Inc. | Denver, CO 80203 | Oil & Gas Operator | Dec 2019 |
| 54 | Central Valley Gas Storage LLC | | Gas Operator | Sep 2025 |
| 55 | Century Exploration Resources LLC | | Oil & Gas Operator | Dec 2015 |
| 56 | Century Production Inc | | Oil & Gas Operator | Dec 1986 |
| 57 | CFT Oil & Gas LLC | | Oil Operator | Sep 2025 |
| 58 | Chaim Nathan & Edie Bato | | Oil & Gas Operator | Aug 2025 |
| 59 | Challenger Minerals Inc. | | Oil & Gas Operator | Dec 1991 |
| 60 | Chalmers-Santa Fe LLC | | Oil & Gas Operator | Dec 2007 |
| 61 | Chambers & Mouren | | Oil & Gas Operator | Oct 2025 |
| 62 | Champlin Petroleum Co. | Rock Springs, WY 82902 | Oil & Gas Operator | Mar 1991 |
| 63 | Channel Exploration Company | | Oil & Gas Operator | Feb 1997 |
| 64 | Chaparral Petroleum Inc. | | Oil Operator | Aug 2025 |
| 65 | Charles W. Hinesley | | Oil & Gas Operator | Dec 1991 |
| 66 | Chemassist L.L.C. | | Oil & Gas Operator | Sep 2025 |
| 67 | Chester F. Dolley | | Oil & Gas Operator | Dec 1986 |
| 68 | Chevron USA Inc | Midland, TX 79706 | Oil & Gas Operator | Nov 2025 |
| 69 | Citadel Exploration Inc. | | Oil Operator | Aug 2025 |
| 70 | City Of Hermosa Beach | | Oil & Gas Operator | Dec 2005 |
| 71 | City Of Huntington Beach (Fire Dept.) | | Oil & Gas Operator | Aug 2025 |
| 72 | City Of Newport Beach | | Oil & Gas Operator | Sep 2025 |
| 73 | City Of Santa Fe Springs | | Oil Operator | Dec 2007 |
| 74 | City Oil Corp. Oper. For | | Oil & Gas Operator | Dec 1989 |
| 75 | Claremont Energy | | Gas Operator | Dec 1993 |
| 76 | Clarence R. Barnett Inc. | | Oil & Gas Operator | Jul 2025 |
| 77 | Clean Energy Systems Placerita Inc. | | Oil & Gas Operator | Aug 2025 |
| 78 | Clearfield Energy Resources & Management Inc. | | Oil & Gas Operator | Dec 1998 |
| 79 | Clint H. Woodington | | Oil Operator | Dec 1994 |
| 80 | Clofas Case Oil Co. | | Oil & Gas Operator | Aug 2025 |
| 81 | Cmo Inc. | | Oil Operator | Sep 2025 |
| 82 | Coal Oil Inc. | | Oil & Gas Operator | Dec 1997 |
| 83 | Coast Supply Company LTD. | | Oil & Gas Operator | Dec 1991 |
| 84 | Coastal Oil & Gas Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2009 |
| 85 | Cockriel Petroleum | | Oil & Gas Operator | Dec 1993 |
| 86 | Coelho & Case Oil Company | | Oil & Gas Operator | Dec 1997 |
| 87 | Coffee Petroleum | | Oil & Gas Operator | Sep 2025 |
| 88 | Columbine Associates | | Oil & Gas Operator | Sep 2025 |
| 89 | Commander Oil Company LTD. | | Oil & Gas Operator | Dec 2021 |
| 90 | Compass Global Resources LLC | | Oil & Gas Operator | Dec 2015 |
| 91 | Concho Petroleum | | Oil & Gas Operator | Dec 1994 |
| 92 | Concordia Resources Inc. | | Oil & Gas Operator | Aug 2025 |
| 93 | Condor Oil Company Inc. | | Oil & Gas Operator | Dec 2000 |
| 94 | Conoco Inc | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 95 | Cooper & Brain Inc. | | Oil & Gas Operator | Sep 2025 |
| 96 | Core Energy LLC | | Oil & Gas Operator | Sep 2025 |
| 97 | Corona Development Co. Inc. | | Oil Operator | Dec 1989 |
| 98 | Costa Loma LTD. | | Oil & Gas Operator | Aug 2025 |
| 99 | Courtland City Lights Assoc. | | Oil Operator | Dec 2005 |
| 100 | Coyote Oil Company. LTD. | | Oil & Gas Operator | Dec 1997 |