| 801 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 802 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 803 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2025 |
| 804 | United Energy Trading LLC | Tulsa, OK 74133 | Oil & Gas Operator | Jan 2025 |
| 805 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 806 | Upland Production Company | Edmond, OK 73083 | Oil & Gas Operator | Apr 2025 |
| 807 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 808 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Apr 2025 |
| 809 | V-F Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 810 | Validus Operating Inc. | Port Aransas, TX 78373 | Oil & Gas Operator | Oct 1998 |
| 811 | Valley Gathering Company | Midland, TX 79702 | Oil & Gas Operator | Feb 1997 |
| 812 | Valley Resources, Inc. | Abilene, TX 79608 | Oil & Gas Operator | Aug 2003 |
| 813 | Vanco Oil & Gas Corp. | Abilene, TX 79604 | Oil & Gas Operator | Apr 2025 |
| 814 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Feb 2021 |
| 815 | Vanguard Permian LLC | Houston, TX 77057 | Oil & Gas Operator | Nov 2018 |
| 816 | Vaquero Operating | FT Stockton, TX 79735 | Oil & Gas Operator | Apr 2025 |
| 817 | Venus Exploration, Inc. | San Antonio, TX 78209 | Oil & Gas Operator | Jul 2013 |
| 818 | Venus Oil Company | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2002 |
| 819 | Vinson Exploration | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 820 | Vinson Exploration, Inc. | Midland, TX 79701 | Gas Operator | Dec 2020 |
| 821 | Vinson Operating Company | Midland, TX 79706 | Oil & Gas Operator | Dec 1999 |
| 822 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Jan 2025 |
| 823 | Vintage Petroleum, LLC | Houston, TX 77210 | Oil & Gas Operator | Dec 2019 |
| 824 | Viola Prod., Inc. | Dallas, TX 75251 | Oil & Gas Operator | Apr 2025 |
| 825 | Vista Resources, Inc. (A) | Midland, TX 79701 | Oil & Gas Operator | Feb 2000 |
| 826 | VRK Oil And Gas, Inc. | Arlington, TX 76016 | Oil & Gas Operator | Mar 2014 |
| 827 | W & W Properties | Westbrook, TX 79565 | Oil & Gas Operator | Aug 2018 |
| 828 | Wagner & Brown, LTD. | Midland, TX 79702 | Oil & Gas Operator | Aug 2014 |
| 829 | Wagner, Duer & Co. | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1999 |
| 830 | Wallen Production Co. | Midland, TX 79702 | Oil & Gas Operator | Aug 1996 |
| 831 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Apr 2025 |
| 832 | Walter Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 833 | Warren American Oil Co | Tulsa, OK 74147 | Oil & Gas Operator | Feb 2025 |
| 834 | Warren American Oil Company LLC | Tulsa, OK 74147 | Oil & Gas Operator | Apr 2025 |
| 835 | Way, Ralph L., Inc. | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 836 | WCWB Energy, LLC | Midland, TX 79701 | Oil Operator | Sep 2015 |
| 837 | West Texas Oil And Gas Oper.,Inc | Houston, TX 77046 | Oil & Gas Operator | Jul 2024 |
| 838 | Westar Energy, Inc. | Midland, TX 79705 | Oil & Gas Operator | Mar 2008 |
| 839 | Westco Oil Company | Ozona, TX 76943 | Oil & Gas Operator | Apr 2025 |
| 840 | Western Natural Gas Company | Shelby, MT 59474 | Oil & Gas Operator | Jan 2025 |
| 841 | Western Reserves Oil Co Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2020 |
| 842 | Westoil LLC | Austin, TX 78747 | Oil & Gas Operator | Apr 2025 |
| 843 | Westport Oil & Gas Company LP | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2007 |
| 844 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Feb 2025 |
| 845 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 846 | Wilbanks, Bruce A. Company | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 847 | Williams, Clayton Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2025 |
| 848 | Willo Oil & Gas Exploration, LLC | Boerne, TX 78006 | Oil & Gas Operator | Jul 2020 |
| 849 | Wilson, W. Corp. | Midland, TX 79705 | Oil & Gas Operator | Mar 1999 |
| 850 | Winchester Production Company | Shreveport, LA 71129 | Oil & Gas Operator | Nov 2008 |
| 851 | Winfrey Oil Co., Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | May 2016 |
| 852 | Winn Exploration Co., Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2025 |
| 853 | WJC, Inc. | Post, TX 79356 | Oil & Gas Operator | Apr 2025 |
| 854 | Wolfcamp Energy, LLC | Midland, TX 79702 | Gas Operator | Apr 2025 |
| 855 | Wood, McShane & Thams | Midland, TX 79702 | Oil & Gas Operator | Oct 1995 |
| 856 | WTG Exploration | Midland, TX 79705 | Oil & Gas Operator | Apr 2025 |
| 857 | WTG Exploration Inc | Midland, TX 79705 | Oil & Gas Operator | Dec 2023 |
| 858 | Wynco Energy, Inc. | Spring, TX 77393 | Oil & Gas Operator | Apr 2025 |
| 859 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 860 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 861 | Xplor Energy Operating Co. | Houston, TX 77079 | Oil & Gas Operator | Jan 2012 |
| 862 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Apr 2025 |
| 863 | Yates Oil & Gas Company | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 864 | Young, Marshall R., Oil Co. | Fort Worth, TX 76107 | Oil & Gas Operator | Mar 2011 |
| 865 | Yucca Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 2025 |
| 866 | Zachry Oil And Gas Properties | Midland, TX 79708 | Oil & Gas Operator | Apr 2025 |
| 867 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 868 | Zephyr Lone Star Oper Co.,L.L.C. | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2025 |