| 1 | K & L Gas & Oil | Homer City, PA 15748-6033 | Gas Operator | Dec 2007 |
| 2 | K & L Gas & Oil Inc | Homer City, PA 15748-6033 | Oil & Gas Operator | Dec 2018 |
| 3 | Kaib & Kaib | Zanesville, OH 43701-6251 | Gas Operator | Dec 2025 |
| 4 | Kavouras Thomas | Apollo, PA 15613-1108 | Oil & Gas Operator | Dec 2023 |
| 5 | Keck Timothy A | Summerville, PA 15864-6301 | Gas Operator | Dec 2014 |
| 6 | Keystone Acquisitions LLC | Anita, PA 15711-9747 | Gas Operator | Dec 2025 |
| 7 | Keystone Energy Oil & Gas Inc | Pittsburgh, PA 15222 | Oil & Gas Operator | Dec 2016 |
| 8 | Kriebel Gas Inc | Clarion, PA 16214-0765 | Oil & Gas Operator | Dec 1999 |
| 9 | Kriebel Minerals Inc | Clarion, PA 16214-6161 | Oil & Gas Operator | Dec 2020 |
| 10 | Kriebel Natural Gas Co LLC | Clarion, PA 16214-6161 | Oil & Gas Operator | Dec 2025 |
| 11 | KSM Energy Inc | Pittsburgh, PA 15238-3156 | Gas Operator | Dec 2024 |
| 12 | Kyle Energy Inc NV | Apollo, PA 15613-0249 | Gas Operator | Dec 1996 |