| 1801 | Calpine Natural Gas Company | Houston, TX 77002 | Oil & Gas Operator | Apr 2002 |
| 1802 | Calpine Natural Gas Company L.P. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 1803 | Calpine Natural Gas L.P. | Houston, TX 77002 | Oil & Gas Operator | Jan 2006 |
| 1804 | Caltex Energy Co. | Luling, TX 78648 | Oil & Gas Operator | Oct 2025 |
| 1805 | Calto Operating Company, Inc. | Dallas, TX 75225 | Oil & Gas Operator | May 2004 |
| 1806 | Calumet Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2019 |
| 1807 | Cam Company | Breckenridge, TX 76424 | Oil & Gas Operator | Sep 2004 |
| 1808 | Cambrian Management LTD | McCaulley, TX 79534 | Oil & Gas Operator | Oct 2025 |
| 1809 | Cambridge Production, Inc. | Amarillo, TX 79120 | Oil & Gas Operator | Nov 2020 |
| 1810 | Camco Saltwater Transport | George West, TX 78022 | Oil Operator | Feb 2015 |
| 1811 | Camco Saltwater Transport,L.L.C. | George West, TX 78022 | Oil Operator | Oct 2025 |
| 1812 | Camden Oil & Gas, Inc. | Farmers BRNCH, TX 75234 | Oil & Gas Operator | Dec 2005 |
| 1813 | Camden Reserves, Inc. | Houston, TX 77019 | Oil & Gas Operator | Mar 2011 |
| 1814 | Camden Resources, Inc. | Farmers BRNCH, TX 75234 | Oil & Gas Operator | Apr 2008 |
| 1815 | Camden Resources, LLC | Blanchard, OK 73010 | Oil & Gas Operator | Dec 2015 |
| 1816 | Camelot Oil And Gas, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2003 |
| 1817 | Cameron Engineering, Inc | Montgomery, TX 77356 | Oil & Gas Operator | Jun 2003 |
| 1818 | Cameron Exploration, Inc. | Longview, TX 75604 | Oil & Gas Operator | Oct 2025 |
| 1819 | Cameron, Paul E., Jr., Inc. | Montgomery, TX 77356 | Oil & Gas Operator | May 2015 |
| 1820 | Caminar Oil & Gas, LLC | Abilene, TX 79602 | Oil & Gas Operator | Aug 2024 |
| 1821 | Camino Real Technologies Inc | Temple, TX 76502 | Oil Operator | Oct 2025 |
| 1822 | Camoil, Inc. | Columbus, TX 78934 | Oil & Gas Operator | Oct 2025 |
| 1823 | Campana Petroleum Company | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 1824 | Campbell Energy LLC | Carmi, IL 62821 | Oil Operator | Jun 2025 |
| 1825 | Campbell, George M. | Lubbock, TX 79490 | Oil & Gas Operator | Apr 2003 |
| 1826 | Campbell, T. K. | Fort Worth, TX 76118 | Oil & Gas Operator | Mar 2006 |
| 1827 | Campsey Minerals | Jacksboro, TX 76458 | Oil & Gas Operator | Oct 2025 |
| 1828 | Camterra Resources, Inc. | Marshall, TX 75671 | Oil & Gas Operator | Oct 2025 |
| 1829 | Can'T Complain Operating Co. | Georgetown, TX 78633 | Oil & Gas Operator | Oct 2025 |
| 1830 | Can-Tex Energy Corp. | Dallas, TX 75231 | Oil & Gas Operator | Nov 2003 |
| 1831 | Canadian River Trading Co II | Katy, TX 77449 | Oil & Gas Operator | Oct 2025 |
| 1832 | Canan Mowrey Operating, LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 1833 | Canan Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 1834 | Candelero Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 1835 | Candleridge Oil, Inc. | Fort Worth, TX 76109 | Oil & Gas Operator | Jun 2003 |
| 1836 | Cannan, Morris | San Antonio, TX 78205 | Oil & Gas Operator | Oct 2025 |
| 1837 | Cannon Operating Company LLC | Garland, TX 75043 | Oil Operator | Oct 2025 |
| 1838 | Cantera Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Nov 2017 |
| 1839 | Cantrell Oil Co. | Elbert, TX 76359 | Oil & Gas Operator | Aug 2003 |
| 1840 | Cantro Exploration, Inc. | San Antonio, TX 78270 | Oil & Gas Operator | May 2000 |
| 1841 | Cantu Operating, LLC | McAllen, TX 78504 | Oil Operator | Oct 2025 |
| 1842 | Canvas Energy LLC | Oklahoma City, OK 73142-1839 | Oil & Gas Operator | Jul 2025 |
| 1843 | Canyon Creek Energy Texas, LLC | Tulsa, OK 74136 | Oil & Gas Operator | May 2017 |
| 1844 | Canyon Creek Resources LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 1845 | Canyon Exploration Co. | Amarillo, TX 79105 | Oil & Gas Operator | Jun 2025 |
| 1846 | Canyon Oil & Gas Exploration LLC | San Antonio, TX 78258 | Oil & Gas Operator | May 2002 |
| 1847 | Canyon Operating LLC | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 1848 | Canyon Operating Unit | San Angelo, TX 76904 | Oil & Gas Operator | Sep 1995 |
| 1849 | Canyon Reef Brine LLC | Snyder, TX 79550 | Oil Operator | Oct 2025 |
| 1850 | Canyon Ridge Energy LLC | Iowa Park, TX 76367 | Oil Operator | Nov 2024 |
| 1851 | Cap Operating Inc. | Borger, TX 79008 | Oil & Gas Operator | Oct 2025 |
| 1852 | Capataz Operating Inc | Midland, TX 79702 | Oil & Gas Operator | Sep 2020 |
| 1853 | Capco Offshore Of Texas, Inc. | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 1854 | Capco Offshore, Inc. | Irving, TX 75063 | Oil & Gas Operator | May 2012 |
| 1855 | Capco Resources Corporation | Irving, TX 75016 | Oil & Gas Operator | Mar 2004 |
| 1856 | Capco Resources Of Texas, Inc | Irving, TX 75063 | Oil & Gas Operator | Jun 2003 |
| 1857 | Cape Operating, Inc. | Longview, TX 75608 | Oil & Gas Operator | Nov 2007 |
| 1858 | Cape, Randy | Tyler, TX 75703 | Oil & Gas Operator | Mar 2008 |
| 1859 | Capio Oil & Gas, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2015 |
| 1860 | Capital A Corp. | San Antonio, TX 78279 | Oil & Gas Operator | Jun 2002 |
| 1861 | Capital Star Oil & Gas, Inc. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 1862 | Capitan Energy, Incorporated | Carlsbad, NM 88221 | Oil & Gas Operator | Oct 2025 |
| 1863 | Capitol Operating & Expl., Inc. | Austin, TX 78766 | Oil & Gas Operator | Feb 2001 |
| 1864 | Capitol Well Servicing Co., Inc. | Oklahoma City, OK 73143 | Oil & Gas Operator | May 2023 |
| 1865 | Capps, R. Oil Corp. | Midland, TX 79704 | Oil & Gas Operator | Oct 2002 |
| 1866 | Caprock Energy, Inc. | Denton, TX 76205 | Oil & Gas Operator | Apr 1993 |
| 1867 | Caprock Engineering, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Nov 2018 |
| 1868 | Caprock Exploration, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Oct 2025 |
| 1869 | Caprock Operating, Inc. | Midland, TX 79708 | Oil & Gas Operator | Dec 2007 |
| 1870 | Caprock, Inc. | Ralls, TX 79357 | Oil & Gas Operator | Mar 2013 |
| 1871 | Capstone Cactus Operating Comp. | Hennessey, OK 73742 | Oil & Gas Operator | Oct 2025 |
| 1872 | Capstone Natural Res II, LLC | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2020 |
| 1873 | Capstone Natural Resources, LLC | Tulsa, OK 74136 | Oil & Gas Operator | May 2015 |
| 1874 | Capturepoint LLC | Allen, TX 75013 | Oil & Gas Operator | Oct 2025 |
| 1875 | Caraway Operating Co. | San Angelo, TX 76902 | Oil & Gas Operator | Oct 2025 |
| 1876 | Caraway, Robert | Cisco, TX 76437 | Oil & Gas Operator | Oct 2025 |
| 1877 | Caraway, Robert R. | Cisco, TX 76437 | Oil & Gas Operator | Oct 2025 |
| 1878 | Carbon Economy LLC | Chickasha, OK 73023 | Oil & Gas Operator | Jul 2025 |
| 1879 | Carbon Field Energy, L.L.C. | Kilgore, TX 75663 | Oil Operator | Apr 2019 |
| 1880 | Carbon Oil Inc | Vidor, TX 77670 | Oil & Gas Operator | Oct 2025 |
| 1881 | Carburante Exploration Co, LTD. | Granbury, TX 76048 | Oil & Gas Operator | Oct 2025 |
| 1882 | Card Operating Company, Inc. | Tyler, TX 75713 | Oil & Gas Operator | Dec 1995 |
| 1883 | Cardinal Energy Company | Rowlett, TX 75088 | Oil & Gas Operator | Oct 2025 |
| 1884 | Cardinal Operating Corporation | Waxahachie, TX 75165 | Oil & Gas Operator | Jan 1997 |
| 1885 | Cardinal Producing Co. | Abilene, TX 79606 | Oil & Gas Operator | Aug 2003 |
| 1886 | Cardinal Shares, Inc. | West Bloomfld, MI 48322 | Oil & Gas Operator | Mar 2004 |
| 1887 | Cardwell Oil Corporation | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 1888 | Cardwell'S U Bar Oil | Manor, TX 78653 | Oil & Gas Operator | Oct 2025 |
| 1889 | Carey, Shirley L. Trust | Abilene, TX 79608 | Oil & Gas Operator | Oct 2025 |
| 1890 | Caribbean Energy LLC II | Cotulla, TX 78014 | Oil & Gas Operator | Oct 2025 |
| 1891 | Caribbean Energy, L.L.C. | Cotulla, TX 78014 | Oil & Gas Operator | Nov 2019 |
| 1892 | Caribe Production Corporation | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 1993 |
| 1893 | Caribou Operating Co. | Granbury, TX 76048 | Oil & Gas Operator | Mar 2010 |
| 1894 | Caribou Operating, Inc. | Granbury, TX 76048 | Oil & Gas Operator | Oct 2025 |
| 1895 | Carken LLC | Andrews, TX 79714 | Oil Operator | Oct 2025 |
| 1896 | Carl Oil & Gas Co. | Bakersfield, CA 93309 | Oil & Gas Operator | Dec 1995 |
| 1897 | Carlon Oil & Gas Co Inc | Derby, KS 67037 | Gas Operator | Dec 2024 |
| 1898 | Carloran Production Corp | Windthorst, TX 76389 | Oil & Gas Operator | Oct 2025 |
| 1899 | Carlow Corp. | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 1900 | Carlson Petroleum Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |