| 601 | MTL 6HC | Bradford County, PA | Gas Property | Mar 2025 |
| 602 | MUDLICK | Armstrong County, PA | Gas Property | Mar 2025 |
| 603 | MUDRICK | Washington County, PA | Gas Property | Dec 2024 |
| 604 | MUELLER | Butler County, PA | Oil & Gas Property | Dec 2019 |
| 605 | MUIR 8 | Westmoreland County, PA | Gas Property | Mar 2025 |
| 606 | MULLEN | Warren County, PA | Oil & Gas Property | Dec 2024 |
| 607 | MULLOY | Susquehanna County, PA | Gas Property | Mar 2025 |
| 608 | MUMAU | Indiana County, PA | Gas Property | Dec 2024 |
| 609 | MUMAU REVOCABLE TRUST 00 | Westmoreland County, PA | Oil & Gas Property | Dec 2024 |
| 610 | MUMFORD | Crawford County, PA | Gas Property | Dec 2024 |
| 611 | MUNCE | Washington County, PA | Oil & Gas Property | Mar 2025 |
| 612 | MUNCE WILLIAM 10060 | Washington County, PA | Gas Property | Mar 2025 |
| 613 | MUNICIPAL AUTHORITY WESTMORELAND C | Westmoreland County, PA | Oil & Gas Property | Dec 2024 |
| 614 | MURACCA | Allegheny County, PA | Gas Property | Dec 2024 |
| 615 | MURDICK-MORGAN | Indiana County, PA | Gas Property | Dec 2024 |
| 616 | MURDOCK | Erie County, PA | Gas Property | Dec 2024 |
| 617 | MURIEL HOSTET | Indiana County, PA | Gas Property | Dec 2024 |
| 618 | MURPHY 07 075 0 | Susquehanna County, PA | Gas Property | Mar 2025 |
| 619 | MURPHY 110 | Washington County, PA | Gas Property | Dec 2024 |
| 620 | MURRAY | Clarion County, PA | Oil & Gas Property | Dec 2024 |
| 621 | MURRAY | Tioga County, PA | Gas Property | Mar 2025 |
| 622 | MURRAY ESTATE | Clearfield County, PA | Gas Property | Dec 2024 |
| 623 | MURRAY LEVINE | Westmoreland County, PA | Oil & Gas Property | Dec 2024 |
| 624 | MURRELL STATES | Indiana County, PA | Oil & Gas Property | Dec 2024 |
| 625 | MURRY HEIRS | Allegheny County, PA | Oil & Gas Property | Dec 2024 |
| 626 | MUSANTE M | Warren County, PA | Oil & Gas Property | Dec 2024 |
| 627 | MUSGRAVE | Beaver County, PA | Oil & Gas Property | Dec 2023 |
| 628 | MUSKO | Armstrong County, PA | Gas Property | Dec 2024 |
| 629 | MUSKOVICH PHILIP 12080 | Washington County, PA | Gas Property | Mar 2025 |
| 630 | MUSOLINO NV62 | Washington County, PA | Gas Property | Mar 2025 |
| 631 | MUSSER | Indiana County, PA | Gas Property | Dec 2024 |
| 632 | MUSSER | Indiana County, PA | Oil & Gas Property | Dec 2024 |
| 633 | MUSSER | Clarion County, PA | Oil & Gas Property | Dec 2024 |
| 634 | MUSSER | Indiana County, PA | Gas Property | Dec 2024 |
| 635 | MUSSER ASSOCIATES | Indiana County, PA | Gas Property | Dec 2023 |
| 636 | MUSSER FOREST | Indiana County, PA | Gas Property | Dec 2024 |
| 637 | MUSSER FOREST | Indiana County, PA | Gas Property | Dec 2024 |
| 638 | MUSSER FOREST | Indiana County, PA | Gas Property | Dec 2024 |
| 639 | MUSSER FOREST | Indiana County, PA | Gas Property | Dec 2024 |
| 640 | MUTNANSKY UNIT | Fayette County, PA | Gas Property | Mar 2025 |
| 641 | MUZETTE MS | Forest County, PA | Oil & Gas Property | Dec 2024 |
| 642 | MV JONES ET UX | Clarion County, PA | Gas Property | Dec 2022 |
| 643 | MY TB INVESTMENTS LLC 6076 | Tioga County, PA | Gas Property | Mar 2025 |
| 644 | MYERS | Venango County, PA | Gas Property | Dec 2024 |
| 645 | MYERS | Warren County, PA | Oil & Gas Property | Dec 2024 |
| 646 | MYERS | Clearfield County, PA | Gas Property | Dec 2024 |
| 647 | MYERS | Washington County, PA | Gas Property | Dec 2024 |
| 648 | MYERS | Westmoreland County, PA | Gas Property | Dec 2024 |
| 649 | MYERS | Washington County, PA | Gas Property | Dec 2024 |
| 650 | MYERS | Mercer County, PA | Oil & Gas Property | Dec 2024 |
| 651 | MYERS 00 | Armstrong County, PA | Gas Property | Dec 2024 |
| 652 | MYERS R | Susquehanna County, PA | Gas Property | Mar 2025 |
| 653 | MYERS UNIT | Bradford County, PA | Gas Property | Mar 2025 |
| 654 | MYERS UNIT | Lycoming County, PA | Gas Property | Mar 2025 |
| 655 | MYERS UNIT | Venango County, PA | Gas Property | Dec 2024 |
| 656 | MYERS V | Venango County, PA | Oil & Gas Property | Dec 2023 |
| 657 | MYRTLE MACKENDRICK | Indiana County, PA | Gas Property | Dec 2024 |
| 658 | MYRTLE SHUMAKER | Armstrong County, PA | Gas Property | Dec 2024 |
| 659 | MYSTIC BROOKE | Indiana County, PA | Gas Property | Dec 2024 |