| 1 | Alliance Petroleum Corporation | Canton, OH 44718-2553-2553 | Oil & Gas Operator | Dec 2019 |
| 2 | Allied Oil Field Services LTD | Willoughby, OH 44094 | Oil & Gas Operator | Dec 2021 |
| 3 | Alsid Oil & Gas | Hanoverton,, OH 44423 | Oil & Gas Operator | Dec 2003 |
| 4 | Annarock Petroleum LLC | Cortland, OH 44410 | Oil & Gas Operator | Dec 2023 |
| 5 | Appalachian Expl Inc | Hartville, OH 44632-550-550 | Oil & Gas Operator | Dec 1992 |
| 6 | Atlas Energy Group Inc | Uniontown, OH 44685-9575-9575 | Oil & Gas Operator | Dec 2011 |
| 7 | Atlas Noble LLC | Fort Worth, TX 76116-5423-5423 | Oil & Gas Operator | Jun 2020 |
| 8 | Atwood Energy Inc | Port Washington, OH 43837-9214-9214 | Oil & Gas Operator | Dec 1993 |
| 9 | Atwood Resources Inc | Houston, TX 72151-89-89 | Oil & Gas Operator | Dec 1993 |
| 10 | Autumn Ridge Enterprises LLC | Wooster, OH 44691 | Oil & Gas Operator | Dec 2017 |
| 11 | Aw Tipka Oil & Gas Inc | Dover, OH 44622 | Oil & Gas Operator | Dec 2023 |