| 801 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 802 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 803 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2025 |
| 804 | United Energy Operating, LLC | Edmond, OK 73083 | Oil & Gas Operator | Oct 2025 |
| 805 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Jun 2025 |
| 806 | Uplands Resources Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Jun 2025 |
| 807 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Oct 2025 |
| 808 | Valar Petroleum Inc | Houston, TX 77069 | Oil & Gas Operator | May 2006 |
| 809 | Valence Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Oct 2025 |
| 810 | Vantage Point Operating Co | Houston, TX 77057 | Oil & Gas Operator | Dec 2014 |
| 811 | Vastar Resources Inc | Houston, TX 77253 | Oil & Gas Operator | Jun 2025 |
| 812 | Veenker Resources, Inc. | Oklahoma City, OK 73113 | Oil & Gas Operator | Jul 2025 |
| 813 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 814 | VRC Oil & Gas Operating Co | Oklahoma City, OK 73116-1431 | Oil & Gas Operator | Jun 2019 |
| 815 | VVWF Oil Inc | Oklahoma City, OK 73143-7375 | Gas Operator | Feb 1994 |
| 816 | W S Crude Oil Purchasing Inc | Oklahoma City, OK 73129-7613 | Oil & Gas Operator | May 2008 |
| 817 | Waggoner Drilling Company | Bristow, OK 74010-0663 | Oil & Gas Operator | Jan 2014 |
| 818 | Waggoner Oil & Gas Corp | Enid, OK 73703-1152 | Oil & Gas Operator | Jul 2025 |
| 819 | Walker Keith F | Ardmore, OK 73401 | Oil & Gas Operator | Jan 2019 |
| 820 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Oct 2025 |
| 821 | Walsh & Watts Inc | Aledo, TX 76008 | Oil & Gas Operator | Oct 2025 |
| 822 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Jun 2025 |
| 823 | Washita Oil And Gas, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 824 | Washita Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2006 |
| 825 | Waterford Energy Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 1998 |
| 826 | Weinkauf Petroleum, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2025 |
| 827 | Weiser-Brown Operating Company | Magnolia, AR 71754 | Oil & Gas Operator | Oct 2025 |
| 828 | Wessely Energy Company | Dallas, TX 75206 | Oil & Gas Operator | May 2001 |
| 829 | Western Mountain Resources LLC | Cogan Station, PA 17728 | Oil & Gas Operator | Jun 2025 |
| 830 | Western Oil And Gas Development Corp | Oklahoma City, OK 73103-3735 | Oil & Gas Operator | Jul 2025 |
| 831 | Weststar Oil & Gas Inc | Edmond, OK 73013 | Oil & Gas Operator | Jul 2025 |
| 832 | Whitaker Energy Inc | Humble, TX 77346-1798 | Oil & Gas Operator | Jul 2025 |
| 833 | White Goat Resources LLC | Yukon, OK 73099 | Oil & Gas Operator | Jul 2025 |
| 834 | White Oak Production Company | Conway, AR 72034 | Oil & Gas Operator | Sep 2005 |
| 835 | Whiting Oil And Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 836 | Whitmar Exploration Company | Denver, CO 80202 | Oil & Gas Operator | Apr 2025 |
| 837 | Whitmar Operating Company | Tulsa, OK 74103-3515 | Oil & Gas Operator | Apr 2009 |
| 838 | Wildhorse Oil & Gas Corporation | Ardmore, OK 73402 | Oil & Gas Operator | May 2019 |
| 839 | Wildhorse Operating Company | Ardmore, OK 73402 | Oil & Gas Operator | Oct 2025 |
| 840 | Will Energy Corporation | Dallas, TX 75201 | Oil & Gas Operator | Jun 2025 |
| 841 | Williford Energy Company | Tulsa, OK 74135 | Oil & Gas Operator | Oct 2025 |
| 842 | Williford Resources, L.L.C. | Tulsa, OK 74136-1020 | Oil & Gas Operator | Jul 2025 |
| 843 | Wimberley James A | Dallas, TX 75229-6180 | Oil & Gas Operator | Nov 2014 |
| 844 | Witty Thomas E | Enid, OK 73703 | Oil & Gas Operator | Mar 2008 |
| 845 | WLW Oil & Gas LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Jul 2025 |
| 846 | Woods Petroleum Corporation | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 847 | Worldwide Energy Corp. | Freer, TX 78357 | Oil & Gas Operator | Jan 1997 |
| 848 | WR Oil & Gas LLC | Plano, TX 75024-3523 | Oil & Gas Operator | Jul 2025 |
| 849 | Wynn-Crosby Operating LP | Dallas, TX 75201 | Oil & Gas Operator | Jun 2025 |
| 850 | Xeric Oil & Gas Corporation | Midland, TX 79702 | Oil & Gas Operator | Apr 2014 |
| 851 | Xog Operating LLC | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 852 | XTO Energy Inc. | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 853 | Yarhola Production Company | Drumright, OK 74030 | Oil & Gas Operator | Jun 2025 |
| 854 | Young H Inc | Edmond, OK 73013 | Oil & Gas Operator | Oct 1993 |
| 855 | Zarvona Energy LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 856 | Zeal Production Company | Sperry, OK 74073-4714 | Oil & Gas Operator | Jul 2025 |
| 857 | Zeiders Bros Oil & Gas Co LLC | Edmond, OK 73003 | Oil & Gas Operator | Jun 2025 |
| 858 | Zenergy Inc | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2025 |
| 859 | Zinke & Trumbo LTD | Tulsa, OK 74105 | Oil & Gas Operator | Sep 2017 |