| 7801 | Delta Operating Company | | Oil Operator | Mar 1987 |
| 7802 | Delta Operating Corporation | | Oil & Gas Operator | Feb 2024 |
| 7803 | Delta Petro Corp Of Colorado | Houston, TX 77010-3089 | Gas Operator | Dec 2003 |
| 7804 | Delta Petroleum Company | Houston, TX 77267 | Oil Operator | Aug 1996 |
| 7805 | Delta Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2024 |
| 7806 | Delta Petroleum Corp Of Co | | Oil & Gas Operator | Oct 2010 |
| 7807 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 7808 | Delta Producers, Inc | Greenville, MS 38703 | Oil & Gas Operator | Dec 2023 |
| 7809 | Delta Producing Corporation | | Oil & Gas Operator | Dec 1996 |
| 7810 | Delta Production Services, LLC | | Oil & Gas Operator | Aug 2002 |
| 7811 | Delta Royalties LLC | | Oil & Gas Operator | Dec 2024 |
| 7812 | Delta Sierra Oil & Gas LLC | | Gas Operator | Jan 2018 |
| 7813 | Deltaus Corporation | | Oil & Gas Operator | Oct 1985 |
| 7814 | Deltex Minerals Inc. | Peachtree Cty, GA 30269 | Oil & Gas Operator | Jul 2025 |
| 7815 | Deltex Petroleum | | Oil Operator | Nov 1994 |
| 7816 | Delwintex Oil & Gas Prop., Inc. | Lubbock, TX 79423 | Oil & Gas Operator | Aug 2003 |
| 7817 | Dem Operations Inc | Lamont, OK 74643-5010 | Oil & Gas Operator | May 2025 |
| 7818 | Demambro, Gene Brian | Mayville, NY 14757 | Gas Operator | Dec 2024 |
| 7819 | Demand Energy, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Jul 1999 |
| 7820 | Demco Oil & Gas Company | Blackwell, OK 74631-4203 | Oil & Gas Operator | Mar 2025 |
| 7821 | Demers - Fleming | Wichita Falls, TX 76305 | Oil & Gas Operator | Mar 2008 |
| 7822 | Demers Oil Production | Byers, TX 76357 | Oil & Gas Operator | Apr 2002 |
| 7823 | Demier Oil Company | Tulsa, OK 74105-2128 | Oil & Gas Operator | Nov 2008 |
| 7824 | Deminex U.S. Oil Company | | Oil & Gas Operator | Jan 1998 |
| 7825 | Demiran Production, Inc. | | Oil Operator | Mar 2008 |
| 7826 | Demo Oil Co | | Oil Operator | Jan 2020 |
| 7827 | Demoss, L. V. | Graham, TX 76450 | Oil & Gas Operator | May 2004 |
| 7828 | Dempsey & Rowe | | Oil Operator | Aug 1986 |
| 7829 | Dempsey, Wayne L | | Oil & Gas Operator | Mar 2011 |
| 7830 | Den Cal, Inc. | Borger, TX 79007 | Oil & Gas Operator | Jul 2025 |
| 7831 | Den-Kay Corp. | Plano, TX 75074 | Oil Operator | Aug 2009 |
| 7832 | Denali Exploration, Inc. | Amarillo, TX 79109 | Oil & Gas Operator | Nov 2018 |
| 7833 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 7834 | Denali Petroleum, LLC | Arlington, TX 76006 | Oil Operator | Mar 2021 |
| 7835 | Denbury Management, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Dec 1999 |
| 7836 | Denbury Offshore, Inc. | | Oil & Gas Operator | Nov 2004 |
| 7837 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Jul 2025 |
| 7838 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 7839 | Denchfield, Fred | Neal, KS 66863 | Oil Operator | Dec 1997 |
| 7840 | Denex Petroleum Corp. | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 7841 | Denex, Inc. | | Oil & Gas Operator | Jul 1983 |
| 7842 | Denham Danny D | Kellyville, OK 74039 | Oil & Gas Operator | May 2025 |
| 7843 | Denham Operating Company | Tulsa, OK 74101-3627 | Oil & Gas Operator | Aug 2022 |
| 7844 | Denhart & Denhart | Brownwood, TX 76804 | Oil & Gas Operator | Dec 2001 |
| 7845 | Deni Frank R | | Oil Operator | Dec 2022 |
| 7846 | Denis Roberts Oil | | Oil Operator | Mar 2025 |
| 7847 | Denman J M Oil C | | Oil Operator | Mar 1994 |
| 7848 | Denman-Friesen Co. | Lufkin, TX 75901 | Oil & Gas Operator | Nov 2006 |
| 7849 | Denmark Oil | Wichita, KS 67212 | Oil & Gas Operator | May 2000 |
| 7850 | Dennett'S Inc | Enid, OK 73701-1851 | Oil & Gas Operator | Apr 2014 |
| 7851 | Denney Don | Citrus Heights, CA 95611-2473 | Oil Operator | Aug 2023 |
| 7852 | Dennis & Broun | Bullard, TX 75757 | Oil & Gas Operator | Sep 2003 |
| 7853 | Dennis & Davis Oil Co. | Nocona, TX 76255 | Oil & Gas Operator | Jul 2025 |
| 7854 | Dennis Don Oil Company | Grady, OK 73569-9998 | Oil Operator | Jan 2002 |
| 7855 | Dennis Fitzpatrick Rev. Trust | Sterling, KS 67579 | Gas Operator | Mar 2025 |
| 7856 | Dennis Langlitz | Carlsbad, NM 88220 | Oil Operator | Jul 2009 |
| 7857 | Dennis Lloyd D | Fleming, OH 45729 | Oil & Gas Operator | Dec 2024 |
| 7858 | Dennis Oil & Gas LLC | Jefferson, OH 44047 | Oil & Gas Operator | Dec 2024 |
| 7859 | Dennis, Don | Grady, OK 73545 | Oil & Gas Operator | Mar 1998 |
| 7860 | Dennison George | Tulsa, OK 74112-6732 | Oil & Gas Operator | Apr 2020 |
| 7861 | Denny'S Inc. | Horseshoe Bay, TX 78657 | Oil & Gas Operator | Dec 2000 |
| 7862 | Denny, Arthur Gene | Independence, KS 67301 | Oil Operator | Oct 1996 |
| 7863 | Denoco Inc. | Plano, TX 75086 | Oil & Gas Operator | Mar 2008 |
| 7864 | Denova | | Oil Operator | Jan 1989 |
| 7865 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 7866 | Denpac Corporation | Colorado SPGS, CO 80922 | Oil & Gas Operator | Jul 2025 |
| 7867 | Densmore, Winfield F. Densmore, Debra L. | Lakewood, NY 14750 | Gas Operator | Dec 2024 |
| 7868 | Denteco Oil Company LLC | Abilene, TX 79604 | Oil & Gas Operator | Jul 2025 |
| 7869 | Denton Exploration, Inc. | Dallas, TX 75219 | Oil & Gas Operator | Jul 2025 |
| 7870 | Denton Oil & Gas | Argyle, TX 76226 | Oil Operator | Dec 2014 |
| 7871 | Denver Energy Exploration,LLC | Canyon Lake, TX 78133 | Oil Operator | Jul 2025 |
| 7872 | Denveramerican Petro LLC | | Oil & Gas Operator | May 2006 |
| 7873 | Denveramerican Petroleum, A LTD Liability Co | Denver, CO 80203 | Oil & Gas Operator | Sep 1997 |
| 7874 | Department Of Conservation | | Oil Operator | Dec 2005 |
| 7875 | Department Of Energy | Casper, WY 82601 | Oil & Gas Operator | Jan 2015 |
| 7876 | Depco Inc. | Denver, CO 80202 | Oil & Gas Operator | Apr 2014 |
| 7877 | Depco, Inc. & Texas Pacific Oil Co. | | Oil Operator | Jul 1995 |
| 7878 | Depriest, Howard Joseph & Susan M. | East Aurora, NY 14052 | Gas Operator | Dec 2024 |
| 7879 | Depuy Drilling Co | Marietta, OH 45750 | Oil & Gas Operator | Dec 2024 |
| 7880 | Derae Oil Company | Seminole, OK 74868-2617 | Oil & Gas Operator | Feb 1997 |
| 7881 | Deran Resources, Inc. | Spencer, WV 25276 | Oil & Gas Operator | Dec 2021 |
| 7882 | Derby Exploration LLC | Okc, OK 73102 | Oil & Gas Operator | May 2025 |
| 7883 | Derby Oil & Gas Corp | Cumberland, OH 43732 | Oil & Gas Operator | Dec 1986 |
| 7884 | Derby Oil Of Texas | Ventura, CA 93003 | Oil & Gas Operator | May 1996 |
| 7885 | Derby Operating Corp | Wooster, OH 44691 | Oil & Gas Operator | Dec 2024 |
| 7886 | Dernick Resources, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Jan 2002 |
| 7887 | Derrick Exploration, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Jan 2003 |
| 7888 | Derrick Oil & Gas, Inc. | Rosharon, TX 77583 | Oil & Gas Operator | Aug 2003 |
| 7889 | Derrick Petroleu | | Oil Operator | Sep 1994 |
| 7890 | Derrick Petroleum Inc | Bladensburg, OH 43005 | Oil & Gas Operator | Dec 2024 |
| 7891 | Derrick Resources Inc. | Henryetta, OK 74437-4249 | Oil & Gas Operator | Apr 2025 |
| 7892 | Derrick-Amer Oil | | Oil Operator | Dec 1991 |
| 7893 | Derwen Operating Company | Houston, TX 77098 | Gas Operator | Dec 2009 |
| 7894 | Des Oil Inc/Osage Only | | Oil Operator | Nov 1998 |
| 7895 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | Jul 2025 |
| 7896 | Desco Corp | Columbus, OH 43085 | Oil & Gas Operator | Dec 1989 |
| 7897 | Desco Oil Company | Houston, TX 77056 | Oil & Gas Operator | Feb 2017 |
| 7898 | Desco-Medders | | Oil & Gas Operator | Jun 1984 |
| 7899 | Desert Eagle Operating LLC | | Gas Operator | May 2025 |
| 7900 | Desert Mountain Energy Corp. | Carson, NV 89701 | Gas Operator | May 2025 |