| 801 | Cattlemans Oil Operations | | Oil Operator | Dec 2009 |
| 802 | Cattlemans Oil Operations LLC | Hays, KS 67601 | Oil Operator | Dec 2019 |
| 803 | Caturus Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Jul 2026 |
| 804 | Caulkins Oil Company | Aztec, NM 87410 | Oil & Gas Operator | Oct 2024 |
| 805 | Cavalcade Operating Company LLC | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2017 |
| 806 | Cavalier Oil & Gas, Inc. | Buchanan Dam, TX 78609 | Oil & Gas Operator | Jul 2026 |
| 807 | Cavalier Oil Co. Et Al | | Oil Operator | Jan 1986 |
| 808 | Cavalier Petroleum | Shelby, MT 59474 | Oil & Gas Operator | Oct 2014 |
| 809 | Cavalry Resources LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Jun 2010 |
| 810 | Cavendish Petro Of Oh Inc | Zanesville, OH 43701 | Oil & Gas Operator | Dec 1989 |
| 811 | Cavenham Energy Resources Inc. | | Oil & Gas Operator | Apr 1991 |
| 812 | Cavenham Energy Resrces Inc JV | | Oil Operator | Mar 1991 |
| 813 | Cavenham Forest Ind., Inc. | | Oil & Gas Operator | Nov 1987 |
| 814 | Cavenham Forest Ind., Inc. J V | | Oil Operator | Nov 1987 |
| 815 | Cavilla Energy, Inc. | Longview, TX 75606 | Oil Operator | Jul 2026 |
| 816 | Cavillo Oil Company LC Of Texas | Marshall, TX 75671 | Oil & Gas Operator | Jul 2026 |
| 817 | Cavillo Oil Corporation | Marshall, TX 75670 | Oil & Gas Operator | Jun 1998 |
| 818 | Cavins Oilfield Services, LLC. | | Oil Operator | Apr 2006 |
| 819 | Caw Prop LP | Dayton, PA 16222-1624 | Gas Operator | Dec 2025 |
| 820 | Cawell Energy, LLC | Spring, TX 77379 | Oil Operator | Jul 2026 |
| 821 | Cayman Exploration Corp | Tulsa, OK 74119-1323 | Oil & Gas Operator | Jun 2001 |
| 822 | Cayman Resources Corporation | Tulsa, OK 74119-1323 | Oil & Gas Operator | Jun 2001 |
| 823 | Caza Exploration Company | | Oil Operator | Nov 1991 |
| 824 | Caza Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Jul 2026 |
| 825 | Cazador Operating, LLC | Midland, TX 79702 | Oil & Gas Operator | Jul 2026 |
| 826 | Cazar Energy Inc | Austin, TX 78734 | Oil & Gas Operator | Jul 2026 |
| 827 | CB Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Nov 2017 |
| 828 | CB Oil Company | Drumright, OK 74030 | Oil & Gas Operator | May 2026 |
| 829 | Cbase Corporation | | Oil & Gas Operator | May 2026 |
| 830 | CBL Resources LLC | Tulsa, OK 74136-6308 | Oil & Gas Operator | May 2026 |
| 831 | CBM Gas Company LLC | Dewey, OK 74029 | Oil & Gas Operator | Aug 2020 |
| 832 | CBM Partners Corporation | Overland Park, KS 66221 | Oil Operator | Aug 2015 |
| 833 | Cbmoncrief Operating, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2026 |
| 834 | CBN Operating Corp. | Austin, TX 78746 | Oil & Gas Operator | Jul 2026 |
| 835 | Cbo Oil And Gas, LLC | Stillwater, OK 74075-8793 | Oil & Gas Operator | May 2026 |
| 836 | CBR Oil Company | Lytle, TX 78052 | Oil & Gas Operator | Jul 1997 |
| 837 | CBS Energy LLC | Oklahoma City, OK 73142-4437 | Oil & Gas Operator | Apr 2026 |
| 838 | CBS Operating Corp | Midland, TX 79702 | Oil & Gas Operator | Aug 2012 |
| 839 | CCF, Inc. | Snyder, TX 79550 | Oil & Gas Operator | Apr 1998 |
| 840 | CCGM Exploration & Prod.,L.C. | Austin, TX 78738 | Oil & Gas Operator | Jul 2026 |
| 841 | Cci East Texas Upstream LLC | Houston, TX 77002 | Oil & Gas Operator | Jan 2021 |
| 842 | Cci Gulf Coast Upstream LLC | Teague, TX 75860 | Oil & Gas Operator | Mar 2021 |
| 843 | Cci Robinson'S Bend LLC | | Gas Operator | May 2026 |
| 844 | CCM Enterprises, Inc | | Oil & Gas Operator | Oct 1985 |
| 845 | CCRP Operating Inc | Denver, CO 80202 | Oil & Gas Operator | Aug 2024 |
| 846 | CCS Investments Inc | Bartlesville, OK 74006-1941 | Oil Operator | Apr 2026 |
| 847 | CCV, Inc. | Houston, TX 77019 | Oil & Gas Operator | Sep 1994 |
| 848 | CD Consulting & Operating Co. | Bridgeport, TX 76426 | Oil & Gas Operator | Jul 2026 |
| 849 | CD Resources Company | San Antonio, TX 78217 | Oil & Gas Operator | Mar 2002 |
| 850 | CDC Oil, LLC | Chanute, KS 66720 | Oil Operator | Jan 2026 |
| 851 | CDC Operating Company | Dallas, TX 75218 | Oil & Gas Operator | Jul 2026 |
| 852 | CDG Inc | Sapulpa, OK 74066-6339 | Oil Operator | Oct 2020 |
| 853 | CDJ Oil Co. | Albany, TX 76430 | Oil & Gas Operator | Jul 2025 |
| 854 | CDJ Oil Company, LLC | Albany, TX 76430 | Oil & Gas Operator | Jul 2026 |
| 855 | CDM Oil & Gas | | Oil & Gas Operator | Apr 2017 |
| 856 | CDS Oil Company | Tulsa, OK 74147-1514 | Oil & Gas Operator | Mar 2015 |
| 857 | CDX Gas, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2009 |
| 858 | CDX Rio, LLC | Farmington, NM 87401 | Oil & Gas Operator | Aug 2009 |
| 859 | Cec Operations LLC | Udall, KS 67146 | Oil & Gas Operator | Mar 2026 |
| 860 | Cecil Brand | | Oil & Gas Operator | Mar 2002 |
| 861 | Cecil Lee'S Co | Tatum, NM 88267 | Oil Operator | Jan 2003 |
| 862 | Cedar Bend Oil Company | Colorado City, TX 79512 | Oil & Gas Operator | Jul 2026 |
| 863 | Cedar Creek Consulting Inc | | Oil Operator | Jan 2025 |
| 864 | Cedar Grove Energy Corp. | | Oil Operator | Sep 2009 |
| 865 | Cedar Oil Company | Midland, TX 79707 | Oil & Gas Operator | Jul 2026 |
| 866 | Cedar Point Oil Company | Baytown, TX 77520 | Oil & Gas Operator | Aug 2003 |
| 867 | Cedar Resources Corporation | Gillette, WY 82717 | Gas Operator | Dec 2010 |
| 868 | Cedar Ridge Energy, Inc. | Coleman, TX 76834 | Oil & Gas Operator | Jul 2026 |
| 869 | Cedar Ridge Operating Co LLC | Durango, CO 81303 | Gas Operator | Dec 2009 |
| 870 | Cedar Valley Energy Inc | Wooster, OH 44691 | Oil & Gas Operator | Dec 2021 |
| 871 | Cedarhill Operating Company, L.L.C. | | Oil Operator | Dec 2007 |
| 872 | Cedyco Corporation | Houston, TX 77227 | Oil & Gas Operator | Nov 2008 |
| 873 | Cegx Of Texas LLC | Eastland, TX 76448 | Oil Operator | Mar 2018 |
| 874 | Ceh Operating LLC | | Oil & Gas Operator | Jun 2026 |
| 875 | Cei Operating LLC | Katy, TX 77449 | Oil & Gas Operator | Jul 2026 |
| 876 | Cei Petroleum Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Jul 2016 |
| 877 | Cei Production Company | Dallas, TX 75225 | Oil & Gas Operator | Sep 1998 |
| 878 | Ceja Corporation | Tulsa, OK 74172 | Oil & Gas Operator | Apr 2026 |
| 879 | Ceka Gas, Div Of GTC | | Oil & Gas Operator | May 1988 |
| 880 | Cel Properties LLC | | Oil & Gas Operator | Jan 2025 |
| 881 | Celero Energy II, LP | Midland, TX 79701 | Oil & Gas Operator | Jul 2026 |
| 882 | Celero Energy LP | Midland, TX 79701 | Oil & Gas Operator | May 2011 |
| 883 | Celeron Oil & Gas Company | | Oil & Gas Operator | Dec 1987 |
| 884 | Celsius Energy Company | Denver, CO 80202-1558 | Oil & Gas Operator | Mar 2000 |
| 885 | Celt Oil, Inc. | | Oil & Gas Operator | Jun 1986 |
| 886 | Cemco Oil | Corsicana, TX 75110 | Oil & Gas Operator | Jul 2026 |
| 887 | Cemco Operating Inc | Bartlet, OH 45713 | Oil & Gas Operator | Dec 2005 |
| 888 | Cemco-Edison No. 1 (F.R.) Partnership | | Oil & Gas Operator | Dec 2000 |
| 889 | Cement Oil Company | Cement, OK 73017-9234 | Oil & Gas Operator | May 2026 |
| 890 | Cemoil Inc | Chickasha, OK 73018 | Oil & Gas Operator | May 2026 |
| 891 | Cen Cal Drilling Inc. | | Oil & Gas Operator | Dec 1994 |
| 892 | Cenco, Inc. | | Oil & Gas Operator | Mar 2022 |
| 893 | Cenergy Exploration Company | Dallas, TX 75231 | Oil & Gas Operator | Sep 2000 |
| 894 | Cenergy Resources LLC | | Oil & Gas Operator | Jan 2026 |
| 895 | Cenestia Energy Inc | | Oil & Gas Operator | Dec 1998 |
| 896 | Cenex | | Oil & Gas Operator | Dec 1996 |
| 897 | Cenex Inc. | | Oil & Gas Operator | Dec 1994 |
| 898 | Ceniza Petroleum, Inc. | Portland, TX 78374 | Oil & Gas Operator | Jul 2026 |
| 899 | Cenla Oil Company, LLC | | Oil Operator | Dec 2024 |
| 900 | Cenpat Operating LLC | Houston, TX 77042-3044 | Oil & Gas Operator | Apr 2026 |