| 30001 | Trail Ridge Energy Partners, LLC | Grapevine, TX 76051 | Oil & Gas Operator | Sep 2025 |
| 30002 | Trail Ridge Energy PRTNS II LLC | Grapevine, TX 76051 | Oil & Gas Operator | Jun 2017 |
| 30003 | Trailblazer Energy LLC | Plano, TX 75075 | Oil & Gas Operator | Sep 2025 |
| 30004 | Trailblazer Energy Resources, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Dec 2025 |
| 30005 | Trailblazer Oil & Gas LLC | Goliad, TX 77963 | Oil & Gas Operator | Dec 2025 |
| 30006 | Trailhead Exploration, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2025 |
| 30007 | Traillour Oil Co. | | Oil & Gas Operator | Mar 1990 |
| 30008 | Trans Atlantic Ener Corp | Caldwell, OH 43724 | Oil & Gas Operator | Dec 1993 |
| 30009 | Trans Atlantic Resource Corp | Tulsa, OK 74136-5709 | Oil & Gas Operator | Nov 1998 |
| 30010 | Trans Energy, Inc. | St. Marys, WV 26170 | Oil & Gas Operator | Dec 2017 |
| 30011 | Trans Ocean Oil, Inc. | | Oil & Gas Operator | Sep 1980 |
| 30012 | Trans Pacific Oi | | Oil & Gas Operator | May 1995 |
| 30013 | Trans Pacific Oil Corporation | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 30014 | Trans Resource D | | Oil Operator | May 1991 |
| 30015 | Trans Terra Corp Int'L | Amarillo, TX 79159-0370 | Oil & Gas Operator | Jul 1993 |
| 30016 | Trans Terra Corp., International | Amarillo, TX 79159 | Oil & Gas Operator | Feb 2009 |
| 30017 | Trans Texas Minerals Company | Austin, TX 78714 | Oil & Gas Operator | Aug 1999 |
| 30018 | Trans-Gulf Petroleum Corp | | Oil & Gas Operator | Sep 1999 |
| 30019 | Trans-Pacific Oil & Gas Inc. | | Oil & Gas Operator | Mar 1982 |
| 30020 | Trans-Pecos Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 30021 | Trans-Sabine Pipeline Corp | | Oil Operator | Mar 2009 |
| 30022 | Trans-Tex Operating LLC | Dallas, TX 75367 | Oil & Gas Operator | Dec 2025 |
| 30023 | Trans-Texas Energy Group LLC | Mineral Wells, TX 76068 | Oil & Gas Operator | Jul 2015 |
| 30024 | Trans-Western Exploration Inc | Dallas, TX 75240 | Oil & Gas Operator | Mar 1993 |
| 30025 | Trans-Western Operating Company | Golden, CO 80402 | Oil Operator | Jun 2025 |
| 30026 | Transamer Petro Corp | Pittsburgh, PA 15222-3510 | Gas Operator | Dec 1985 |
| 30027 | Transamerica Energy Corp. | Atlanta, GA 30356 | Oil & Gas Operator | Dec 2025 |
| 30028 | Transamerica Oil | | Oil & Gas Operator | Sep 1992 |
| 30029 | Transamerica Oil Corporation | Hutchinson, KS 67504 | Gas Operator | Mar 2025 |
| 30030 | Transamerican Energy LTD | Dallas, TX 75231-1075 | Oil & Gas Operator | Apr 2014 |
| 30031 | Transamerican Energy/Toce Oil | | Oil & Gas Operator | Dec 1994 |
| 30032 | Transamerican Natural Gas Corp. | Houston, TX 77032 | Oil & Gas Operator | Aug 2000 |
| 30033 | Transamerican-Swepi-Toce Oil | | Oil & Gas Operator | Apr 1990 |
| 30034 | Transatlantic Expl LTD Dba Ravenna Oil | Beattyville, KY 41311 | Oil Operator | Dec 2023 |
| 30035 | Transatlantic Petr (USA) Corp. | Dallas, TX 75206 | Oil & Gas Operator | Dec 2025 |
| 30036 | Transco Exploration Company | | Oil & Gas Operator | Jul 1989 |
| 30037 | Transco Oil & Gas Inc. | | Gas Operator | Dec 1992 |
| 30038 | Transcoastal Operating LLC | Dallas, TX 75252-5646 | Oil & Gas Operator | Mar 2015 |
| 30039 | Transcontinental Company | Haltom City, TX 76148-4122 | Oil & Gas Operator | Aug 2025 |
| 30040 | Transcontinental Gas P/L Corp. | | Oil & Gas Operator | Dec 2009 |
| 30041 | Transcontinental Gas Pipeline Co LLC | | Oil Operator | Jan 2025 |
| 30042 | Transcontinental Minerals Corp. | The Woodlands, TX 77380 | Oil & Gas Operator | Dec 2008 |
| 30043 | Transcontinental Oil & Gas Inc | Aurora, OH 44202 | Oil & Gas Operator | Dec 2024 |
| 30044 | Transcontinental Oil Corp. | | Oil & Gas Operator | Sep 1985 |
| 30045 | Transcontinental Shale L.L.C. | Austin, TX 78717 | Oil & Gas Operator | Feb 2016 |
| 30046 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 30047 | Transglobe Oil & Gas Corporation | Littleton, CO 801222710 | Oil & Gas Operator | Dec 1999 |
| 30048 | Transhorizon Energy Inc | Cheyenne, WY 82003 | Oil & Gas Operator | Jul 2023 |
| 30049 | Transit Energy Inc | North Lawrence, OH 44666 | Oil & Gas Operator | Dec 2024 |
| 30050 | Transoil, Inc. | Oklahoma City, OK 73129 | Oil & Gas Operator | Dec 2025 |
| 30051 | Transok LLC | Oklahoma City, OK 73124-0300 | Oil & Gas Operator | Jul 2020 |
| 30052 | Transpac Petroleum Inc. | | Oil & Gas Operator | Dec 1995 |
| 30053 | Transpacific Energy, LLC | Katy, TX 77450 | Oil & Gas Operator | Dec 2025 |
| 30054 | Transpetco I | Shreveport, LA 71101 | Oil & Gas Operator | May 2009 |
| 30055 | Transpetco Transport Company | Shreveport, LA 71101-5370 | Oil Operator | Jun 2008 |
| 30056 | Transtexas Gas Corporation | Houston, TX 77265 | Oil & Gas Operator | Aug 2005 |
| 30057 | Transworld Expl. & Prod., Inc. | | Oil & Gas Operator | Mar 2004 |
| 30058 | Transworld Systems Petroleum Inc | Denver, CO 80202 | Oil & Gas Operator | Sep 2025 |
| 30059 | Trap Rock Oil Company | Cambridge, MA 02138 | Oil & Gas Operator | Nov 2005 |
| 30060 | Trap Rock Oil, LTD. | Houston, TX 77005 | Oil & Gas Operator | Dec 2025 |
| 30061 | Trapp Oil Oper - | | Oil Operator | Aug 1989 |
| 30062 | Traton Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Mar 2019 |
| 30063 | Travco Well Servicing LLC | Okmulgee, OK 74447 | Oil Operator | Jul 2025 |
| 30064 | Travelers Oil Company | Amarillo, TX 79102 | Oil & Gas Operator | Dec 2025 |
| 30065 | Travell Energy, Inc | | Oil Operator | Dec 2023 |
| 30066 | Traver Oil & Gas Corporation | | Oil & Gas Operator | Sep 2000 |
| 30067 | Traver Oil Company | | Oil & Gas Operator | Sep 2000 |
| 30068 | Traver-Patterson Petroleum Inc | | Oil & Gas Operator | May 1990 |
| 30069 | Travers Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 30070 | Traverse Oil Co | | Oil & Gas Operator | Nov 1983 |
| 30071 | Traverse Oil Co And Federal Oil Co | | Oil & Gas Operator | Nov 1983 |
| 30072 | Travis | Houston, TX 77057 | Oil Operator | Dec 2025 |
| 30073 | Travis Coomer DRLG Co | | Oil Operator | Dec 2023 |
| 30074 | Travis E. Duren | | Oil Operator | Jul 1995 |
| 30075 | Travis Oil Co | Los Angeles, CA 90024 | Oil Operator | Jan 1990 |
| 30076 | Travis Operating, LLC | Kingwood, TX 77345 | Oil & Gas Operator | Dec 2025 |
| 30077 | Travis Peak Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Jul 2025 |
| 30078 | Travis, J. J., Trustee | Rockport, TX 78382 | Oil & Gas Operator | Dec 1996 |
| 30079 | Traxler, Joyce | Le Roy, NY 14482 | Gas Operator | Dec 2024 |
| 30080 | Traynor Oil & Gas Inc | Claremont, CA 91711-2837 | Oil & Gas Operator | Jan 2024 |
| 30081 | TRC Cypress Group LLC | | Oil & Gas Operator | Sep 2025 |
| 30082 | TRC Operating Company Inc. | | Oil & Gas Operator | Oct 2025 |
| 30083 | Tre'J Exploration, Inc. | | Gas Operator | Dec 1991 |
| 30084 | Treadaway Oil Co. | Balmorhea, TX 79718 | Oil & Gas Operator | Dec 2025 |
| 30085 | Treadstone Energy Partners, LLC | Houston, TX 77070 | Oil & Gas Operator | Jun 2016 |
| 30086 | Treadstone Energy PRTNR Op, LLC | Katy, TX 77494 | Oil & Gas Operator | Dec 2025 |
| 30087 | Treat Howard | Okmulgee, OK 74447 | Oil & Gas Operator | Oct 2014 |
| 30088 | Trebole Operating Company | | Oil Operator | Jul 1979 |
| 30089 | Treco Oil Company | Albany, TX 76430 | Oil & Gas Operator | Dec 2025 |
| 30090 | Tredegar Properties, Inc. | | Oil Operator | Jun 1990 |
| 30091 | Tree Operating, LLC | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 30092 | Trees Oil Compan | | Oil Operator | Jan 1995 |
| 30093 | Trejim Operators, LLC | Pampa, TX 79065 | Oil & Gas Operator | Dec 2025 |
| 30094 | Trek Aec, LLC | Wichita, KS 67202 | Oil & Gas Operator | Jun 2025 |
| 30095 | Trek Exploration, Inc. | Pampa, TX 79065 | Oil & Gas Operator | Dec 2025 |
| 30096 | Trek Oil & Gas, Inc | Houston, TX 77002 | Oil Operator | Mar 1998 |
| 30097 | Trek Operating, LLC | Tulsa, OK 741520098 | Oil & Gas Operator | Mar 2021 |
| 30098 | Trek Petroleum Company, Inc. | Midland, TX 79707 | Oil & Gas Operator | Dec 2025 |
| 30099 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Dec 2025 |
| 30100 | Tremo Corporation | Toronto, KS 66777 | Oil Operator | May 1998 |