| 901 | Celsius Energy Company | Denver, CO 80202-1558 | Oil & Gas Operator | Mar 2000 |
| 902 | Celt Oil, Inc. | | Oil & Gas Operator | Jun 1986 |
| 903 | Cemco Oil | Corsicana, TX 75110 | Oil & Gas Operator | Jun 2025 |
| 904 | Cemco Operating Inc | Bartlet, OH 45713 | Oil & Gas Operator | Dec 2005 |
| 905 | Cemco-Edison No. 1 (F.R.) Partnership | | Oil & Gas Operator | Dec 2000 |
| 906 | Cement Oil Company | Cement, OK 73017-9234 | Oil & Gas Operator | Apr 2025 |
| 907 | Cemoil Inc | Cement, OK 73017-0563 | Oil & Gas Operator | Apr 2025 |
| 908 | Cen Cal Drilling Inc. | | Oil & Gas Operator | Dec 1994 |
| 909 | Cenco, Inc. | | Oil & Gas Operator | Mar 2022 |
| 910 | Cenergy Exploration Company | Dallas, TX 75231 | Oil & Gas Operator | Sep 2000 |
| 911 | Cenergy Resources LLC | | Oil & Gas Operator | Apr 2025 |
| 912 | Cenestia Energy Inc | | Oil & Gas Operator | Dec 1998 |
| 913 | Cenex | | Oil & Gas Operator | Dec 1996 |
| 914 | Cenex Inc. | | Oil & Gas Operator | Dec 1994 |
| 915 | Ceniza Petroleum, Inc. | Portland, TX 78374 | Oil & Gas Operator | Jun 2025 |
| 916 | Cenla Oil Company, LLC | | Oil Operator | Dec 2024 |
| 917 | Cenpat Operating LLC | Houston, TX 77042-3044 | Oil & Gas Operator | Mar 2025 |
| 918 | Centaur Exploration LLC | Evanston, WY 82931 | Oil & Gas Operator | Jun 2025 |
| 919 | Centaur Petroleum Corporation | Fort Worth, TX 76101 | Oil & Gas Operator | Jun 2025 |
| 920 | Centaur Resources Inc | Oklahoma City, OK 73142-6804 | Oil & Gas Operator | Apr 2025 |
| 921 | Centennial Energy | Thermopolis, WY 82443 | Oil & Gas Operator | Feb 2025 |
| 922 | Centennial Energy Company | Torrance, CA 90503 | Oil Operator | Jan 2000 |
| 923 | Centennial Energy Corp. | Big Lake, TX 76932 | Oil & Gas Operator | Jan 1997 |
| 924 | Centennial Exploration, Inc. | | Oil & Gas Operator | Dec 1985 |
| 925 | Centennial Resource Prod, LLC | Denver, CO 80202 | Oil & Gas Operator | Aug 2023 |
| 926 | Centennial Resources Inc | Drumright, OK 74030-1234 | Oil & Gas Operator | Dec 2007 |
| 927 | Center Dean Dba Center Operating Co | | Oil & Gas Operator | Jul 2003 |
| 928 | Center Junction Corp | | Oil Operator | Mar 2009 |
| 929 | Center Oil Company | Ada, OK 74821-0584 | Oil Operator | May 2003 |
| 930 | Center Production Company LLC | Ada, OK 74820 | Oil Operator | Mar 2025 |
| 931 | Center Start, LC | Kilgore, TX 75663 | Oil & Gas Operator | May 2008 |
| 932 | Centerfire Resources | Springerville, AZ 85938 | Oil & Gas Operator | Jun 2025 |
| 933 | Centergate Resources LLC | | Oil & Gas Operator | Dec 2024 |
| 934 | Centerpoint Energy FLD Ser Inc | | Oil Operator | Feb 2011 |
| 935 | Centerpoint Water Disposal Inc | | Oil & Gas Operator | Aug 1984 |
| 936 | Centex Energy, LLC | Bryan, TX 77802 | Oil & Gas Operator | Jun 2025 |
| 937 | Centex Pipe & Equipment, Inc. | Luling, TX 78648 | Oil & Gas Operator | Jun 2025 |
| 938 | Central Basin Oil Inv. Inc. | Southlake, TX 76092 | Oil & Gas Operator | Jun 2025 |
| 939 | Central California Oil Co. | Fish Camp, CA 93623 | Oil & Gas Operator | Apr 2025 |
| 940 | Central Crude Corp. | Wichita, KS 67206 | Oil Operator | Mar 2014 |
| 941 | Central Crude, Inc. | | Oil & Gas Operator | Jul 2014 |
| 942 | Central Drilling Company, USA | Midland, TX 79710 | Oil & Gas Operator | May 2006 |
| 943 | Central Energy C | | Oil & Gas Operator | Jun 1994 |
| 944 | Central Energy Co Inc | Newark, OH 43055 | Oil & Gas Operator | Dec 1998 |
| 945 | Central Energy Corporation | Wichita, KS 67202 | Oil & Gas Operator | Nov 1998 |
| 946 | Central Energy Group, LLC | | Oil & Gas Operator | Dec 2020 |
| 947 | Central Energy Producing Company | San Antonio, TX 78217 | Oil & Gas Operator | Sep 2003 |
| 948 | Central Gulf Petroleum Inc | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2025 |
| 949 | Central Hydrocarbons, LLC | | Oil Operator | Dec 2013 |
| 950 | Central Lease Inc. | | Oil & Gas Operator | Dec 1998 |
| 951 | Central Min Oper Co, Inc. | | Gas Operator | Mar 1994 |
| 952 | Central Mineral Management Inc | | Oil & Gas Operator | Jul 1990 |
| 953 | Central Mineral Operating Co,Inc | San Antonio, TX 78216 | Oil & Gas Operator | Apr 1997 |
| 954 | Central Montana Resources, LLC | San Antonio, TX 78209 | Oil Operator | Jul 2015 |
| 955 | Central Oil Field Supply | Lancaster, OH 43130 | Oil & Gas Operator | Dec 1991 |
| 956 | Central Operating Inc | Denver, CO 80202 | Oil & Gas Operator | Apr 2025 |
| 957 | Central Operating, LLC | | Oil & Gas Operator | Feb 2025 |
| 958 | Central Pacific Group, Inc. | | Oil & Gas Operator | Dec 2003 |
| 959 | Central Pacific Resources | | Oil Operator | Apr 2025 |
| 960 | Central Park Energy | | Oil & Gas Operator | Dec 1991 |
| 961 | Central Plains Oil&Gas Corp. (A) | Bryan, TX 77802 | Oil & Gas Operator | Mar 2003 |
| 962 | Central Resources Inc | Denver, CO 80203 | Oil & Gas Operator | Dec 2019 |
| 963 | Central States Energy LLC | Scottsdale, AZ 85260 | Gas Operator | Apr 2012 |
| 964 | Central States O | | Oil & Gas Operator | May 1992 |
| 965 | Central Texas Operating, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Jun 2025 |
| 966 | Central Transmission Systems Co | | Oil & Gas Operator | Apr 2015 |
| 967 | Central Valley Gas Storage LLC | | Gas Operator | Apr 2025 |
| 968 | Central Wyoming Resources LTD | Glenrock, WY 82637 | Oil Operator | Jul 2021 |
| 969 | Centrex Operating Company | Tulsa, OK 74105 | Oil & Gas Operator | Mar 2025 |
| 970 | Centura Inc | | Oil & Gas Operator | Feb 1985 |
| 971 | Centurion Exploration Company | Houston, TX 77042 | Oil & Gas Operator | May 2009 |
| 972 | Centurion Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Jul 2009 |
| 973 | Centurion Oil & Gas Op. Co. Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 1998 |
| 974 | Centurion Oil Inc | Oklahoma City, OK 73120 | Oil & Gas Operator | May 1992 |
| 975 | Centurion Operating Corporation | Rockwall, TX 75087 | Oil & Gas Operator | Jun 2025 |
| 976 | Centurion Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 977 | Century Assets Corporation | Houston, TX 77056 | Oil Operator | Jun 2025 |
| 978 | Century Energy | Gillette, WY 82717 | Oil & Gas Operator | Dec 1996 |
| 979 | Century Energy, Inc. | | Oil & Gas Operator | Aug 1989 |
| 980 | Century Exploration Company | | Oil & Gas Operator | Dec 2003 |
| 981 | Century Exploration Houston, Inc | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2011 |
| 982 | Century Exploration Houston, LLC | Austin, TX 78702 | Oil & Gas Operator | Jan 2016 |
| 983 | Century Exploration N.O. LLC | | Oil & Gas Operator | Jun 2017 |
| 984 | Century Exploration N.O., Inc. | | Oil & Gas Operator | Sep 2011 |
| 985 | Century Exploration New Orleans, LLC | | Oil & Gas Operator | Mar 2008 |
| 986 | Century Exploration Resources LLC | | Oil & Gas Operator | Dec 2015 |
| 987 | Century Mineral Corporation | | Oil & Gas Operator | Dec 1990 |
| 988 | Century Mining, LLC | | Gas Operator | Dec 2021 |
| 989 | Century Offshore MGMT. Corp. | | Oil & Gas Operator | Dec 1999 |
| 990 | Century Oil & Gas Corporation | | Oil & Gas Operator | Dec 1987 |
| 991 | Century Oil And Gas LLC | Katy, TX 77494 | Oil & Gas Operator | Apr 2025 |
| 992 | Century Oil Company Inc | Troy, MI 48098 | Oil Operator | Dec 2024 |
| 993 | Century Oil Mana | | Oil Operator | Apr 1987 |
| 994 | Century Oil, Inc. | | Oil Operator | Apr 2022 |
| 995 | Century Petroleum | Nowata, OK 74048 | Oil & Gas Operator | Dec 2000 |
| 996 | Century Petroleum, Inc. | Jacksboro, TX 76458 | Oil & Gas Operator | Jun 2025 |
| 997 | Century Production Inc | | Oil & Gas Operator | Dec 1986 |
| 998 | Century Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Jun 2025 |
| 999 | Century Royalty 2000 GP, LLC | Conroe, TX 77301 | Oil & Gas Operator | Jun 2020 |
| 1000 | Century Stimulation & Eng LLC | | Oil Operator | Dec 2015 |