| 801 | Unicon Producing Company | Houston, TX 75252 | Gas Operator | Mar 1994 |
| 802 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 803 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Jul 2026 |
| 804 | United Energy Operating, LLC | Edmond, OK 73083 | Oil & Gas Operator | Jul 2026 |
| 805 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Apr 2026 |
| 806 | United Production Company LLC | Edmond, OK 73003 | Oil & Gas Operator | May 2026 |
| 807 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jul 2026 |
| 808 | Validus Energy II Midcon LLC | Denver, CO 80202 | Oil & Gas Operator | Jul 2026 |
| 809 | Valjohn Energy Corporation | Dover, OK 73734 | Oil & Gas Operator | Apr 2026 |
| 810 | Vaquero Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2026 |
| 811 | Veenker Resources Inc | Oklahoma City, OK 73113 | Oil & Gas Operator | May 2026 |
| 812 | Viersen & Cochran Drilling Company | | Oil & Gas Operator | May 2015 |
| 813 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Apr 2026 |
| 814 | Vista Energy Inc | Yukon, OK 73085-0827 | Oil & Gas Operator | Mar 2015 |
| 815 | Vitol Inc. | Houston, TX 77098 | Oil & Gas Operator | Sep 2023 |
| 816 | VRC Oil & Gas Operating Co | Oklahoma City, OK 73116-1431 | Oil & Gas Operator | Jun 2019 |
| 817 | W C T Operating LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2026 |
| 818 | W S Crude Oil Purchasing Inc | Oklahoma City, OK 73129-7613 | Oil & Gas Operator | May 2008 |
| 819 | Walker Corporation (The) | Oklahoma City, OK 73156 | Oil & Gas Operator | May 2006 |
| 820 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Jul 2026 |
| 821 | Walsh Jr F Howard | Fort Worth, TX 76102-4773 | Oil & Gas Operator | Feb 2026 |
| 822 | Wapi Operating LLC | McCurtain, OK 74944 | Oil & Gas Operator | Apr 2026 |
| 823 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Apr 2026 |
| 824 | Warren American Oil Company LLC | Tulsa, OK 74147 | Oil & Gas Operator | Jul 2026 |
| 825 | Washita Oil And Gas, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 826 | Washita Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2006 |
| 827 | Weatherly Oil & Gas, LLC | Dallas, TX 75206 | Oil & Gas Operator | Jul 2026 |
| 828 | Wehlu Producers Inc | Edmond, OK 73083-5278 | Oil & Gas Operator | Sep 2002 |
| 829 | Wellco Energy Inc | Harrah, OK 73045 | Oil & Gas Operator | Apr 2026 |
| 830 | Wes-Tex Drilling Company | Abilene, TX 79604 | Oil & Gas Operator | Jan 2000 |
| 831 | Western Oil And Gas Development Corp | Oklahoma City, OK 73103-3735 | Oil & Gas Operator | May 2026 |
| 832 | Western Petroleum Company Inc | Tulsa, OK 74170-2676 | Oil & Gas Operator | Apr 2020 |
| 833 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | May 2026 |
| 834 | Wheeler Energy Co. | Tulsa, OK 74101 | Oil & Gas Operator | Apr 2026 |
| 835 | Wheeler Energy, LLC | Tulsa, OK 74101 | Oil & Gas Operator | Jul 2026 |
| 836 | White Goat Resources LLC | Yukon, OK 73099 | Oil & Gas Operator | Apr 2026 |
| 837 | White Mike Oil Field Service | Edmond, OK 73034 | Oil & Gas Operator | Jan 2013 |
| 838 | White Operating Company | Oklahoma City, OK 73159-7136 | Oil & Gas Operator | Apr 2026 |
| 839 | White Star Petroleum LLC | Oklahoma City, OK 73116-7906 | Oil & Gas Operator | Dec 2025 |
| 840 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Jul 2026 |
| 841 | Whitley Oil & Gas Inc | Owasso, OK 74055 | Oil & Gas Operator | Jun 2009 |
| 842 | Whitmar Exploration Company | Denver, CO 80202 | Oil & Gas Operator | Apr 2026 |
| 843 | Whitmar Operating Company | Tulsa, OK 74103-3515 | Oil & Gas Operator | Apr 2009 |
| 844 | Wildhorse Oil & Gas Corporation | Ardmore, OK 73402 | Oil & Gas Operator | May 2019 |
| 845 | Williams Reid Oil Co | Dallas, TX 75234 | Oil & Gas Operator | Mar 2026 |
| 846 | Wilshire Enterprises Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 847 | Wilshire Oil LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | Apr 2026 |
| 848 | Windsor Energy Group LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Aug 2021 |
| 849 | Wishbone Oil & Gas | Noble, OK 73068 | Oil & Gas Operator | Mar 2007 |
| 850 | WLW Oil & Gas LLC | Kingfisher, OK 73750 | Oil & Gas Operator | May 2026 |
| 851 | Wolverine Exploration Company | Houston, TX 77002 | Oil & Gas Operator | May 2019 |
| 852 | Woods Petroleum Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 853 | WR Oil & Gas LLC | Plano, TX 75024-3523 | Oil & Gas Operator | Apr 2026 |
| 854 | Wynn-Crosby Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Apr 2026 |
| 855 | Xanadu Exploration Company | Broken Arrow, OK 74014 | Oil & Gas Operator | May 2026 |
| 856 | Y D F Inc | Oklahoma City, OK 73128 | Oil & Gas Operator | May 2026 |
| 857 | Yarhola Production Company | Drumright, OK 74030 | Oil & Gas Operator | Apr 2026 |
| 858 | Young Tommy Oil Inc | Woodward, OK 73802-0893 | Oil & Gas Operator | Apr 2026 |
| 859 | Z G Operating LLC | Oklahoma City, OK 73134-5038 | Oil & Gas Operator | Nov 2009 |
| 860 | Z G Exploration Inc | Oklahoma City, OK 73112 | Oil & Gas Operator | Feb 2005 |
| 861 | Zeiders Bros. Oil & Gas Company, L.L.C. | Edmond, OK 73003 | Oil & Gas Operator | Apr 2026 |
| 862 | Zephyr Operating Co LLC | Oklahoma City, OK 73118-6035 | Oil & Gas Operator | Apr 2026 |
| 863 | Zilkha Energy Company | Houston, TX 77046 | Oil & Gas Operator | Oct 2002 |
| 864 | ZP Disposal Systems LLC | Kingfisher, OK 73750 | Oil Operator | May 2026 |