| 501 | MIRABELLI UNIT P&G WAREHOUSE 1 MIRABELLI 4H | Wyoming County, PA | Gas Property | Jun 2026 |
| 502 | MITCHELL | Greene County, PA | Oil & Gas Property | Dec 2025 |
| 503 | MITCHELL | Susquehanna County, PA | Gas Property | Jun 2026 |
| 504 | MITCHELL | Clearfield County, PA | Gas Property | Dec 2025 |
| 505 | MITCHELL | Armstrong County, PA | Gas Property | Dec 2025 |
| 506 | MITCHELL | Jefferson County, PA | Gas Property | Dec 2025 |
| 507 | MITCHELL | Clearfield County, PA | Oil & Gas Property | Dec 2025 |
| 508 | MITCHELL | Susquehanna County, PA | Gas Property | Jun 2026 |
| 509 | MITCHELL | Indiana County, PA | Gas Property | Dec 2025 |
| 510 | MITCHELL 456 | Tioga County, PA | Gas Property | Apr 2022 |
| 511 | MITCHELL A 903 | Potter County, PA | Gas Property | Jun 2026 |
| 512 | MITCHELL FARMS | Westmoreland County, PA | Gas Property | Dec 2025 |
| 513 | MITCHELL JAMES UNIT | Washington County, PA | Oil & Gas Property | Jun 2026 |
| 514 | MITCHELL P UNIT | Venango County, PA | Gas Property | Dec 2025 |
| 515 | MIZIA | Washington County, PA | Oil & Gas Property | Dec 2025 |
| 516 | MIZIA JAMES 11676 | Washington County, PA | Gas Property | Jun 2026 |
| 517 | MM&G UNIT | Allegheny County, PA | Gas Property | Dec 2025 |
| 518 | MOBEAR | Bradford County, PA | Gas Property | Jun 2026 |
| 519 | MOCEK JOHN 11222 | Washington County, PA | Gas Property | Jun 2026 |
| 520 | MOGRIDGE C 00 | Susquehanna County, PA | Gas Property | Jun 2026 |
| 521 | MOHAWK | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 522 | MOHAWK LODGE UNIT | Clinton County, PA | Gas Property | Jun 2026 |
| 523 | MOHAWK NORTH UNIT | Clinton County, PA | Gas Property | Jun 2026 |
| 524 | MOHNEY | Jefferson County, PA | Gas Property | Dec 2025 |
| 525 | MOHNEY | Jefferson County, PA | Oil & Gas Property | Dec 2025 |
| 526 | MOHR | Greene County, PA | Oil & Gas Property | Jun 2026 |
| 527 | MOJO | Washington County, PA | Gas Property | Jun 2026 |
| 528 | MOLLY J | Bradford County, PA | Gas Property | Jun 2026 |
| 529 | MOLNAR M | Susquehanna County, PA | Gas Property | Jun 2026 |
| 530 | MOLNAR UNIT | Washington County, PA | Oil & Gas Property | Dec 2013 |
| 531 | MOMYER | Westmoreland County, PA | Gas Property | Dec 2025 |
| 532 | MONARCH 591 | Jefferson County, PA | Gas Property | Jun 2026 |
| 533 | MONARCH PARK | Venango County, PA | Oil Property | Dec 2018 |
| 534 | MONO | Washington County, PA | Gas Property | Jun 2026 |
| 535 | MONOCEROS | Butler County, PA | Gas Property | Jun 2026 |
| 536 | MONRO (03-142-0 | Bradford County, PA | Gas Property | Jun 2026 |
| 537 | MONROE C FENTON | Indiana County, PA | Gas Property | Dec 2025 |
| 538 | MONROEVILLE PARK | Allegheny County, PA | Oil & Gas Property | Dec 2025 |
| 539 | MONROSS | Forest County, PA | Oil Property | Dec 2025 |
| 540 | MONTEPARTE | Westmoreland County, PA | Oil & Gas Property | Dec 2025 |
| 541 | MONTGOMERY | Washington County, PA | Oil Property | Dec 1999 |
| 542 | MONTGOMERY | McKean County, PA | Oil & Gas Property | Dec 2025 |
| 543 | MONTGOMERY | Clarion County, PA | Gas Property | Dec 2025 |
| 544 | MONTGOMERY | Armstrong County, PA | Gas Property | Aug 2019 |
| 545 | MOOD | Fayette County, PA | Gas Property | Dec 2025 |
| 546 | MOODY | McKean County, PA | Oil & Gas Property | Dec 2025 |
| 547 | MOODY BRA | Bradford County, PA | Gas Property | Jun 2026 |
| 548 | MOONEY | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 549 | MOONEY | Greene County, PA | Oil & Gas Property | Dec 2025 |
| 550 | MOONEY | Greene County, PA | Oil & Gas Property | Dec 2025 |
| 551 | MOORE | McKean County, PA | Oil Property | Dec 2025 |
| 552 | MOORE | Lawrence County, PA | Gas Property | Dec 2025 |
| 553 | MOORE | Fayette County, PA | Oil & Gas Property | Dec 2025 |
| 554 | MOORE | Jefferson County, PA | Gas Property | Dec 2025 |
| 555 | MOORE | Greene County, PA | Gas Property | Dec 2025 |
| 556 | MOORE 1 | Susquehanna County, PA | Gas Property | Jun 2026 |
| 557 | MOORE FARM | Bradford County, PA | Gas Property | Jun 2026 |
| 558 | MOORE PARK 12065 | Washington County, PA | Gas Property | Jun 2026 |
| 559 | MOORE RICHARD UNIT | Washington County, PA | Gas Property | Jun 2026 |
| 560 | MOORE, S | Susquehanna County, PA | Gas Property | Jun 2026 |
| 561 | MOOSE | Bradford County, PA | Gas Property | Jun 2026 |
| 562 | MOOSE | Mercer County, PA | Gas Property | Dec 2025 |
| 563 | MORAVEK | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 564 | MORELAND | Crawford County, PA | Oil & Gas Property | Dec 2025 |
| 565 | MORETZ 03 036 | Bradford County, PA | Gas Property | Jun 2026 |
| 566 | MORGAN | Warren County, PA | Oil & Gas Property | Dec 2024 |
| 567 | MORGAN | Allegheny County, PA | Oil & Gas Property | Dec 2025 |
| 568 | MORGAN | Armstrong County, PA | Gas Property | Dec 2025 |
| 569 | MORGAN | Washington County, PA | Oil & Gas Property | Dec 2021 |
| 570 | MORGAN 01 07 | Bradford County, PA | Gas Property | Jun 2026 |
| 571 | MORITZ EDWARD UNIT | Washington County, PA | Gas Property | Jun 2026 |
| 572 | MORRIS | McKean County, PA | Oil Property | Dec 2022 |
| 573 | MORRIS | Armstrong County, PA | Gas Property | Dec 2025 |
| 574 | MORRIS STERN | Indiana County, PA | Gas Property | Dec 2021 |
| 575 | MORRISON | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 576 | MORRISON | Venango County, PA | Oil Property | Dec 1999 |
| 577 | MORRISON | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 578 | MORRISON | Warren County, PA | Gas Property | Dec 2025 |
| 579 | MORRISON RUN | Warren County, PA | Oil & Gas Property | Dec 2025 |
| 580 | MORROW | Greene County, PA | Gas Property | Dec 2025 |
| 581 | MORROW | Butler County, PA | Gas Property | Jun 2026 |
| 582 | MORSE | Bradford County, PA | Gas Property | Jun 2026 |
| 583 | MORTON | Greene County, PA | Oil & Gas Property | Jun 2026 |
| 584 | MOSER | Lycoming County, PA | Gas Property | Jun 2026 |
| 585 | MOSER | McKean County, PA | Oil & Gas Property | Dec 2025 |
| 586 | MOSER WARRANT 3767 | McKean County, PA | Oil & Gas Property | Dec 2008 |
| 587 | MOSHANNON DCNR TRACT 826 | Clearfield County, PA | Gas Property | Dec 2016 |
| 588 | MOUNTAIN GATHERING | Butler County, PA | Oil & Gas Property | Jun 2026 |
| 589 | MOUNTAIN MEADOW | Lycoming County, PA | Gas Property | Jun 2026 |
| 590 | MOUNTAIN RUN HUNTING CLUB (02-153 | Tioga County, PA | Gas Property | Apr 2026 |
| 591 | MOUNTAIN TRAILS INC | Armstrong County, PA | Gas Property | Dec 2025 |
| 592 | MOURER | Butler County, PA | Oil & Gas Property | Jun 2026 |
| 593 | MOWL CHARLES 11760 | Washington County, PA | Gas Property | Jun 2026 |
| 594 | MOWREY | Clearfield County, PA | Gas Property | Dec 2025 |
| 595 | MOWREY | McKean County, PA | Oil & Gas Property | Dec 2025 |
| 596 | MOWREY MARSHBURG | McKean County, PA | Oil & Gas Property | Dec 2020 |
| 597 | MOWRY | Bradford County, PA | Gas Property | Jun 2026 |
| 598 | MOYER BRA | Bradford County, PA | Gas Property | Jun 2026 |
| 599 | MOYLAN | Warren County, PA | Oil & Gas Property | Dec 2024 |
| 600 | MPC SUL | Sullivan County, PA | Gas Property | Jun 2026 |