| 801 | Sundance Operating Co | | Oil & Gas Operator | Jul 2016 |
| 802 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 803 | Superior Production MGMT Inc | Calumet, OK 73014 | Oil & Gas Operator | Mar 2015 |
| 804 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Apr 2025 |
| 805 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 806 | T2 Operating Corporation | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 807 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | May 2025 |
| 808 | Tarrant Tracy Dba Trace Oil | Crescent, OK 73028 | Oil & Gas Operator | Feb 2021 |
| 809 | Tbi Exploration Inc | Englewood, CO 801556525 | Oil & Gas Operator | Jun 2011 |
| 810 | TD Operating Inc | Hinton, OK 73047 | Oil & Gas Operator | May 2025 |
| 811 | Te-Ray Resources, LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Jul 2025 |
| 812 | Technical Energy Services, Inc. | Norman, OK 73070 | Oil & Gas Operator | Apr 2025 |
| 813 | Teepee Oil & Gas Inc | Yukon, OK 73085 | Oil Operator | Dec 2006 |
| 814 | Tekenergy, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Mar 2015 |
| 815 | Tema Oil Company | Amarillo, TX 79101 | Oil & Gas Operator | Jun 2009 |
| 816 | Tenneco Oil Company | Oklahoma City, OK 73125 | Oil & Gas Operator | Apr 2025 |
| 817 | Tennyson Oil & Gas | Muskogee, OK 74401 | Oil Operator | Apr 2025 |
| 818 | Teocalli Exploration LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | May 2025 |
| 819 | Terra Production Company | Okemah, OK 74859-5924 | Oil & Gas Operator | Apr 2020 |
| 820 | Tessera Energy LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Apr 2025 |
| 821 | Tex-Star Production | Dallas, TX 75206 | Oil & Gas Operator | May 2025 |
| 822 | Texaco Expl. And Prod. Inc. | Houston, TX 77236 | Oil & Gas Operator | May 2025 |
| 823 | Texaco Inc | Kingfisher, OK 73750 | Oil & Gas Operator | Dec 2017 |
| 824 | Texaco Oils, Inc. | Tulsa, OK 74102-2420 | Oil & Gas Operator | Jan 2003 |
| 825 | Texas American Oil Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2001 |
| 826 | Texas Meridian Operating Co. Inc | Houston, TX 77079 | Oil & Gas Operator | Oct 1993 |
| 827 | Texasgulf Inc. | Newgulf, TX 77462 | Oil & Gas Operator | Jul 1994 |
| 828 | TGX Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2004 |
| 829 | The Quintin Little Company Inc | Ardmore, OK 73401 | Oil & Gas Operator | May 2025 |
| 830 | Thomas J L Engineering Inc | Edmond, OK 73003-0026 | Oil & Gas Operator | Jul 2016 |
| 831 | Thompson, Joe L., Inc. | Oklahoma City, OK 73132 | Oil & Gas Operator | Oct 2005 |
| 832 | Three Sands Oil Inc | Perry, OK 73077 | Oil & Gas Operator | May 2023 |
| 833 | Tide West Oil Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2021 |
| 834 | Tidemark Exploration | Tulsa, OK 74170 | Oil & Gas Operator | May 2005 |
| 835 | Tilley Oil & Gas, Inc. | Oklahoma City, OK 73172 | Oil & Gas Operator | Jul 2025 |
| 836 | Tipperary Oil & Gas Corp | Denver, CO 80202 | Oil & Gas Operator | May 2014 |
| 837 | Titan Oil & Gas Corporation | Edmond, OK 73013-5417 | Oil & Gas Operator | Apr 2025 |
| 838 | Titan Resources LTD | Limaville, OH 44640 | Oil & Gas Operator | May 2025 |
| 839 | TLS Oil & Gas Inc | Kingfisher, OK 73750-0901 | Oil & Gas Operator | May 2025 |
| 840 | TLS Operating Company | Greenwood VIlge, CO 80111 | Oil & Gas Operator | Dec 2013 |
| 841 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 842 | Tower Oil & Gas Company, Inc. | Englewood, CO 80111 | Oil & Gas Operator | May 2001 |
| 843 | Tpet, Inc. | Dallas, TX 75204 | Oil & Gas Operator | Mar 2008 |
| 844 | Tracer Energy, Inc. | Graham, TX 76450 | Oil & Gas Operator | Nov 1998 |
| 845 | Trail Ridge Energy Partners, LLC | Grapevine, TX 76051 | Oil & Gas Operator | May 2025 |
| 846 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 847 | Transok LLC | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Jul 2020 |
| 848 | Traynor Oil & Gas Inc | Claremont, CA 91711-2837 | Oil & Gas Operator | Jan 2024 |
| 849 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Jul 2025 |
| 850 | Trepel Petroleum Exploration & | | Oil & Gas Operator | Apr 2014 |
| 851 | Triad Energy, Inc. | Oklahoma City, OK 73105-1401 | Oil & Gas Operator | May 2025 |
| 852 | Trigg Drilling Company Inc | Oklahoma City, OK 73105 | Oil & Gas Operator | Jan 2013 |
| 853 | Triple L Management Co Inc | Edmond, OK 73025-2908 | Oil & Gas Operator | Apr 2018 |
| 854 | Tripower Resources, Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2020 |
| 855 | Triumph Energy Partners LLC | Oklahoma City, OK 73102-5804 | Oil & Gas Operator | Apr 2025 |
| 856 | Tulsa Energy Partners LLC | Tulsa, OK 74103-4461 | Oil & Gas Operator | May 2025 |
| 857 | Tulum Corporation | Oklahoma City, OK 73101-0125 | Oil & Gas Operator | Feb 2025 |
| 858 | Turner Resources Inc | Hennessey, OK 73742 | Oil & Gas Operator | Apr 2025 |
| 859 | Twenty First Century Res Inc | Lajolla, CA 92037-7044 | Oil & Gas Operator | Mar 2015 |
| 860 | Twenty/Twenty Oil & Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | May 2025 |
| 861 | Twisted Resources Inc | Blanchard, OK 73010-8463 | Oil & Gas Operator | Apr 2025 |
| 862 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 863 | Txok Energy Resources Company | Tulsa, OK 74172-0140 | Oil & Gas Operator | Feb 2017 |
| 864 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 865 | Unicon Producing Company | Houston, TX 75252 | Gas Operator | Mar 1994 |
| 866 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 867 | Union Texas Petroleum Corp. | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 868 | United Oil Corporation | Denver, CO 80202-3813 | Oil & Gas Operator | Apr 2025 |
| 869 | United Production Company LLC | Edmond, OK 73003 | Oil & Gas Operator | May 2025 |
| 870 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Jul 2025 |
| 871 | Validus Energy II Midcon LLC | Denver, CO 80202 | Oil & Gas Operator | Jul 2025 |
| 872 | Valjohn Energy Corporation | Dover, OK 73734 | Oil & Gas Operator | Apr 2025 |
| 873 | Van Horn Oil & Gas Inc | Tulsa, OK 74170 | Oil & Gas Operator | Nov 1998 |
| 874 | Vantage Point Operating Co | Houston, TX 77057 | Oil & Gas Operator | Dec 2014 |
| 875 | Vargas Oil & Gas LLC | Hennessey, OK 73742 | Gas Operator | Apr 2025 |
| 876 | Vastar Resources Inc | Houston, TX 77253 | Oil & Gas Operator | Mar 2025 |
| 877 | Vector Exploration Inc | Oklahoma City, OK 73142-4430 | Oil & Gas Operator | Dec 2018 |
| 878 | Veenker Resources, Inc. | Oklahoma City, OK 73113 | Oil & Gas Operator | May 2025 |
| 879 | Viersen & Cochran Drilling Company | | Oil & Gas Operator | May 2015 |
| 880 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Apr 2025 |
| 881 | Vista Energy Inc | Yukon, OK 73085-0827 | Oil & Gas Operator | Mar 2015 |
| 882 | Vitol Inc. | Houston, TX 77098 | Oil & Gas Operator | Sep 2023 |
| 883 | VRC Oil & Gas Operating Co | Oklahoma City, OK 73116-1431 | Oil & Gas Operator | Jun 2019 |
| 884 | W M Energy Corp | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2015 |
| 885 | Waggoner Oil & Gas Corp | Enid, OK 73703-1152 | Oil & Gas Operator | May 2025 |
| 886 | Walker Corporation (The) | Oklahoma City, OK 73156 | Oil & Gas Operator | May 2006 |
| 887 | Wallace Oil & Gas Inc | Oklahoma City, OK 73156 | Oil & Gas Operator | Jul 2025 |
| 888 | Ward Oil Company An Okla Corp | McAlester, OK 74501 | Oil & Gas Operator | Feb 1993 |
| 889 | Ward Petroleum Corporation | Enid, OK 73702 | Oil & Gas Operator | Apr 2025 |
| 890 | Warren American Oil Company LLC | Tulsa, OK 74147 | Oil & Gas Operator | Jul 2025 |
| 891 | Warren Drilling Co | Dexter City, OH 45727 | Oil & Gas Operator | Dec 2024 |
| 892 | Warwick Associates LC | Oklahoma City, OK 73112 | Oil & Gas Operator | May 2025 |
| 893 | Waterford Energy Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 1998 |
| 894 | Weatherly Oil & Gas, LLC | Dallas, TX 75206 | Oil & Gas Operator | Jul 2025 |
| 895 | Weaver Energy Corporation | Hennessey, OK 73742-1232 | Oil & Gas Operator | May 2025 |
| 896 | Webb Donna Delan Dba Petrodudes | Crescent, OK 73028 | Oil & Gas Operator | Mar 2025 |
| 897 | Wehlu Producers Inc | Edmond, OK 73083-5278 | Oil & Gas Operator | Sep 2002 |
| 898 | Wellco Energy Inc | Harrah, OK 73045 | Oil & Gas Operator | Apr 2025 |
| 899 | Wentworth Operating Company | Oklahoma City, OK 73162-1863 | Oil & Gas Operator | May 2025 |
| 900 | Western Mountain Resources LLC | Cogan Station, PA 17728 | Oil & Gas Operator | Apr 2025 |