| 4901 | U S Liquids Of La., L.P. | | Oil Operator | Apr 2014 |
| 4902 | U. D. Man, Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Feb 2026 |
| 4903 | U. O. C., Inc. | | Oil Operator | Jun 2019 |
| 4904 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 4905 | U.S. Capital Corp Of Am, Inc. | | Oil & Gas Operator | Aug 1998 |
| 4906 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 4907 | Ultramar Oil & Gas LTD | Houston, TX 77060 | Oil & Gas Operator | Jul 1995 |
| 4908 | Ultramar Production Company | | Oil & Gas Operator | Dec 1991 |
| 4909 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 4910 | Uni Production Company, Inc. | | Oil & Gas Operator | Apr 1988 |
| 4911 | Unifid Oil & Gas Corp. | | Oil & Gas Operator | Mar 1994 |
| 4912 | Union Diversified Investments, Inc. | | Gas Operator | Nov 2024 |
| 4913 | Union Diversified, Inc. | | Gas Operator | Dec 2008 |
| 4914 | Union Drilling &Management Inc | | Gas Operator | Feb 1991 |
| 4915 | Union Expl. Partners, LTD. | | Oil & Gas Operator | Aug 1990 |
| 4916 | Union Gas Operating Company | Spring, TX 77391 | Oil & Gas Operator | Feb 2026 |
| 4917 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 4918 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 4919 | Union Texas Petroleum Corp | Houston, TX 77252-2120 | Oil & Gas Operator | Dec 2014 |
| 4920 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2026 |
| 4921 | United Gas Pipe Line Co. | | Oil Operator | Aug 1993 |
| 4922 | United Investment Group | | Oil Operator | Nov 2004 |
| 4923 | United Operators, Inc. | | Oil Operator | Sep 1999 |
| 4924 | United Petroleum Corporation | Edgwater, CO 80214 | Oil & Gas Operator | May 1996 |
| 4925 | United Southern Resources Inc. | | Gas Operator | Nov 2013 |
| 4926 | United World Energy Corporation | | Oil & Gas Operator | Dec 2024 |
| 4927 | Universal Drilling Company | Denver, CO 80203 | Oil & Gas Operator | Sep 2003 |
| 4928 | Universal Land | | Oil Operator | Dec 2024 |
| 4929 | Universal Oil Co. | | Oil Operator | Jan 2025 |
| 4930 | Universal Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2002 |
| 4931 | Universal Producers, Inc. | | Oil Operator | Jun 2001 |
| 4932 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 4933 | University Field Management LLC | | Oil Operator | Nov 2024 |
| 4934 | Unocal Exploration Corporation | Houston, TX 77001 | Oil & Gas Operator | May 1992 |
| 4935 | Upstream Exploration LLC | Metairie, LA 70002 | Oil & Gas Operator | Jan 2020 |
| 4936 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Feb 2026 |
| 4937 | Us Liquids Of La, LTD | | Oil Operator | Jul 2002 |
| 4938 | Us Oil & Gas Inc | Marietta, OH 45750 | Oil & Gas Operator | Jan 2026 |
| 4939 | Usoil Corporation | | Oil & Gas Operator | Nov 1998 |
| 4940 | V L Pittman PC & Producer, Inc | | Oil & Gas Operator | Jul 1989 |
| 4941 | V. E. Karnes | | Oil Operator | Jun 1989 |
| 4942 | V. H. Brumley | | Oil Operator | Jul 1994 |
| 4943 | V. J. Huff | | Gas Operator | Mar 1981 |
| 4944 | V. Monta Currie, Jr. | | Oil Operator | Jun 2007 |
| 4945 | Vale Petroleum Corporation | Houston, TX 77042 | Gas Operator | Jan 1995 |
| 4946 | Valerius, Inc. & Zine, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Jul 1994 |
| 4947 | Vamos Oil & Gas, LLC | Miami, FL 33129 | Oil & Gas Operator | Feb 2026 |
| 4948 | Van Operating, LTD. | Albany, TX 76430 | Oil & Gas Operator | Feb 2026 |
| 4949 | Van Zanten, Inc. | | Gas Operator | Jan 1990 |
| 4950 | Vanguard Environmental, LLC | | Oil Operator | Nov 2024 |
| 4951 | Vanguard Operating, LLC | Houston, TX 77057 | Oil & Gas Operator | Aug 2019 |
| 4952 | Vanguard Petroleum Corp. | | Gas Operator | Jun 1986 |
| 4953 | Vantage Point Operating Co. | Houston, TX 77057 | Oil & Gas Operator | Dec 2014 |
| 4954 | Vaquero Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 2025 |
| 4955 | Varco Oil | | Oil & Gas Operator | Apr 1991 |
| 4956 | Vast Oil Inc | Fullerton, CA 92832 | Oil & Gas Operator | Mar 2024 |
| 4957 | Vastar Resources Inc | Houston, TX 77253 | Oil & Gas Operator | Sep 2025 |
| 4958 | Vaughn Petroleum, Inc. | Dallas, TX 75219 | Oil & Gas Operator | May 2004 |
| 4959 | Vector Energy Corporation | Houston, TX 77060 | Oil & Gas Operator | Feb 2026 |
| 4960 | Vector Minerals Corporation | Aurora, CO 80015 | Oil & Gas Operator | Nov 2025 |
| 4961 | Vega Oil & Gas MGMT., Inc. | | Oil & Gas Operator | Aug 1981 |
| 4962 | Velandera Energy Partners LLC | | Oil & Gas Operator | Nov 2024 |
| 4963 | Venado Petroleum Corporation | Dallas, TX 75231 | Oil & Gas Operator | May 2012 |
| 4964 | Ventex Operating Corp. | Addison, TX 75001 | Oil & Gas Operator | Feb 2026 |
| 4965 | Venture Oil & Gas, Inc. | Laurel, MS 39440 | Oil & Gas Operator | Dec 2025 |
| 4966 | Venture Oil Company Of Texas | | Oil Operator | Sep 1988 |
| 4967 | Ventures Oil & Gas Of La Inc. | | Oil & Gas Operator | Jun 1999 |
| 4968 | Venvirotek Of Louisiana, Inc. | | Oil Operator | Apr 2002 |
| 4969 | Verado Energy, Inc. | Allen, TX 75013 | Oil & Gas Operator | Oct 2025 |
| 4970 | Vermilion Bay Land Co. | | Oil & Gas Operator | Dec 1994 |
| 4971 | Vermilion Exploration, Inc. | | Oil & Gas Operator | Dec 1982 |
| 4972 | Vermilion Resources, Inc. | Houston, TX 77060 | Oil & Gas Operator | Sep 2009 |
| 4973 | Vermillion Energy & Dev. Corp. | | Oil & Gas Operator | Jul 1991 |
| 4974 | Vern Wilson Energy Inc. | | Oil & Gas Operator | Dec 2011 |
| 4975 | Verna Petroleum Company | | Oil & Gas Operator | Jun 1992 |
| 4976 | Vernon Bradford | | Oil Operator | Apr 1992 |
| 4977 | Vernon E. Faulconer | | Oil & Gas Operator | Dec 1996 |
| 4978 | Vernon E. Faulconer, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Dec 2024 |
| 4979 | Verona Energy, Inc. | | Oil & Gas Operator | Nov 2024 |
| 4980 | Vess Oil Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 4981 | Vetra Exploration And Production LLC | | Oil & Gas Operator | Aug 2012 |
| 4982 | Vibe Resources LLC | | Oil & Gas Operator | Dec 2024 |
| 4983 | Victoria Land & Investment Co. | | Oil & Gas Operator | Jan 1985 |
| 4984 | Victory Financial Group, Inc. | | Oil & Gas Operator | Sep 2002 |
| 4985 | Viking Oil Co. | | Oil & Gas Operator | Dec 1990 |
| 4986 | Viking Resources | | Oil & Gas Operator | Sep 1995 |
| 4987 | Vinbar Oil & Gas, LLC | | Oil & Gas Operator | Jan 2018 |
| 4988 | Vine Energy Operating LP | | Gas Operator | Oct 2021 |
| 4989 | Vine Oil & Gas LP | | Gas Operator | Apr 2021 |
| 4990 | Vintage Petroleum, Inc. | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 4991 | Vinyard And Sons | | Oil & Gas Operator | Oct 2009 |
| 4992 | Virgil L. Pittman | | Oil & Gas Operator | Jun 1983 |
| 4993 | Virgin Offshore U.S.A., Inc. | | Oil & Gas Operator | Oct 2012 |
| 4994 | Virtex Petroleum Company, Inc. | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Jan 2008 |
| 4995 | Vision Natural Res-La, LLC | | Oil Operator | Dec 2024 |
| 4996 | Vista Corporation | | Oil & Gas Operator | Jan 2011 |
| 4997 | Vista Investments | | Gas Operator | Nov 1998 |
| 4998 | Vista Resources LLC | Teague, TX 75860 | Oil & Gas Operator | Feb 2026 |
| 4999 | Vistatex Energy LLC | Houston, TX 77057 | Oil & Gas Operator | Nov 2025 |
| 5000 | Vitol Resources Inc. Of Delaware | | Oil & Gas Operator | Jul 2016 |