| 1 | I. H. Delatte | | Oil & Gas Operator | Jul 1991 |
| 2 | I. W. McKnight,Production | | Oil Operator | Jan 1986 |
| 3 | I.G. Petroleum, L.L.C | | Oil & Gas Operator | Dec 2018 |
| 4 | Iberia Operating Corporation | | Oil & Gas Operator | Jan 2003 |
| 5 | Idc Energy Corp | Warren, PA 16365-0792 | Oil & Gas Operator | Dec 2021 |
| 6 | Ike Lovelady, Inc. | | Oil & Gas Operator | Jun 1985 |
| 7 | Imc Exploration Co. | | Oil & Gas Operator | Oct 1986 |
| 8 | Imperial-American Energy,Inc. | | Oil & Gas Operator | Jul 1978 |
| 9 | Inabnet Est., H. Inabnet, Agt. | | Gas Operator | Jul 2005 |
| 10 | Inactive Operator | | Oil Operator | Dec 1982 |
| 11 | Independent Expl Company | | Oil & Gas Operator | Dec 2000 |
| 12 | Indian Exploration, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Dec 2025 |
| 13 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Dec 2025 |
| 14 | Indigo Haynesville LLC | | Gas Operator | Feb 2018 |
| 15 | Indigo II Louisiana Operating LLC | | Oil & Gas Operator | Feb 2015 |
| 16 | Indigo Minerals LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2022 |
| 17 | Indigo Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2019 |
| 18 | Indrex Inc | Tulsa, OK 74133 | Oil & Gas Operator | Dec 2000 |
| 19 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 20 | Infinity Oil And Gas, L.L.C. | | Oil & Gas Operator | Dec 2024 |
| 21 | Inflow Petroleum Resources LP | Dallas, TX 75240 | Oil & Gas Operator | Sep 2008 |
| 22 | Ingo Energy, LLC | | Oil & Gas Operator | Dec 2016 |
| 23 | Inland Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Aug 2025 |
| 24 | Innovative Resources, Inc. | | Oil Operator | Feb 2022 |
| 25 | Inpetco, Inc. | | Oil & Gas Operator | Aug 1991 |
| 26 | Int'L Petr & Expl Opr Corp | | Oil & Gas Operator | Jan 2012 |
| 27 | Integrated Exploration & Production LLC | | Oil & Gas Operator | Aug 2024 |
| 28 | Intercoast Oil And Gas Company | Tulsa, OK 74136 | Oil & Gas Operator | Jun 1997 |
| 29 | Intercoastal Operating Co. | | Oil Operator | Dec 1980 |
| 30 | International Oil & Gas Corp. | | Oil & Gas Operator | Dec 1986 |
| 31 | Interstate Explorations LLC | Houston, TX 77010 | Oil & Gas Operator | Dec 2025 |
| 32 | Interstate Producing Servs,Inc | | Oil & Gas Operator | May 1987 |
| 33 | Intrepid Drilling, LLC | | Oil & Gas Operator | Jan 2025 |
| 34 | Investco Oil And Gas Inc | | Oil & Gas Operator | Jan 2025 |
| 35 | Investment Trends Corp. | | Gas Operator | Mar 1988 |
| 36 | Iowa Production Company, Inc. | | Oil & Gas Operator | Jan 1992 |
| 37 | Ip Petroleum Company, Inc. | Houston, TX 77210 | Oil & Gas Operator | Mar 2008 |
| 38 | Iron Springs Operating Co. Inc | | Oil & Gas Operator | Jan 2025 |
| 39 | Irvin Operations, Inc. | | Oil Operator | Aug 1996 |
| 40 | Irwin H. Parnes | | Oil Operator | Jun 1982 |
| 41 | Island Petroleum, Inc. | | Gas Operator | Mar 1998 |
| 42 | Itr Petroleum Inc | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |