| 401 | Mays Gas & Coal Co | Clarion, PA 16214-0447 | Oil & Gas Operator | Dec 2023 |
| 402 | MBS Resources Inc | Wilcox, PA 15870-1810 | Oil & Gas Operator | Dec 2023 |
| 403 | McCall Carl E | Fairmount City, PA 16224 | Oil & Gas Operator | Dec 2022 |
| 404 | McComb Oil Inc | Stoneboro, PA 16153-3017 | Oil & Gas Operator | Dec 2023 |
| 405 | McCool John E | Youngsville, PA 16371 | Oil & Gas Operator | Feb 2024 |
| 406 | McKenna Oil Co | Kane, PA 16735-9711 | Oil & Gas Operator | Dec 2004 |
| 407 | MDS Energy Dev LLC | Kittanning, PA 16201-4403 | Oil & Gas Operator | Jan 2024 |
| 408 | MDS Energy LTD | Kittanning, PA 16201-4403 | Gas Operator | Feb 2015 |
| 409 | Mead Oil LLC | Sheffield, PA 16347-1022 | Oil & Gas Operator | Dec 2023 |
| 410 | Medina Res Dev Co LLC | Cambridge Springs, PA 16403-3447 | Oil & Gas Operator | Dec 2023 |
| 411 | Meridian Exploration Corp. | Pittsburgh, PA 15222 | Oil & Gas Operator | Dec 2021 |
| 412 | Meridian Oil & Gas Enterprises Inc | Blairsville, PA 15717-0337 | Oil & Gas Operator | Dec 2003 |
| 413 | Mervin Troyer | Union City, PA 16438-8510 | Gas Operator | Dec 2008 |
| 414 | Mid Amer Natural Resources Inc | Erie, PA 16505-4760 | Gas Operator | Dec 1994 |
| 415 | Mid East Oil Co | Indiana, PA 15701-5378 | Gas Operator | Dec 2006 |
| 416 | Mid-Penn Energy Corporation | Harrisburg, PA 17101-1002 | Gas Operator | Dec 2021 |
| 417 | Mieka LLC | Flower Mound, TX 75028-7446 | Oil & Gas Operator | Dec 2014 |
| 418 | Millennium Oil & Gas Inc | Dexter, KS 67038 | Oil & Gas Operator | Dec 2023 |
| 419 | Minard Run Oil Co | Bradford, PA 16701 | Oil & Gas Operator | Dec 2023 |
| 420 | Minteer & Baker Gas Enterprise | Worthington, PA 16262-0739 | Gas Operator | Dec 2023 |
| 421 | Missing Moon Oil Inc | Knox, PA 16232-4507 | Oil & Gas Operator | Dec 2023 |
| 422 | Mitchell Energy Corp | Houston, TX 77002 | Oil & Gas Operator | Aug 2013 |
| 423 | Monona LLC | Ligonier, PA 15658-0612 | Gas Operator | Dec 2023 |
| 424 | Monroe Res LTD | Fairport, NY 14450-3218 | Gas Operator | Dec 2004 |
| 425 | Mount Chestnut Dev LLC | Butler, PA 16002-3940 | Gas Operator | Dec 2017 |
| 426 | MSL Oil & Gas Corp | Bradford, PA 16701-0151 | Oil & Gas Operator | Dec 2023 |
| 427 | MTN Energy | Aleppo, PA 15310 | Oil & Gas Operator | Dec 2023 |
| 428 | MTN V Oil & Gas Inc | Indiana, PA 15701-8914 | Oil & Gas Operator | Jan 2024 |
| 429 | Murphy Prod Inc | Vanderbilt, PA 15486-1001 | Oil & Gas Operator | Dec 2022 |
| 430 | Mutual Oil & Gas Co | Akron, OH 44313 | Oil & Gas Operator | Dec 2001 |
| 431 | Natl Fuel Gas Supply Corp | Williamsville, NY 14221-5887 | Oil & Gas Operator | Dec 2009 |
| 432 | Natural Energy Dev Corp | Pittsburgh, PA 15241-1548 | Oil & Gas Operator | Dec 2018 |
| 433 | Natural Oil & Gas Corp | Bradford, PA 16701 | Oil & Gas Operator | Dec 2020 |
| 434 | NCL Natural Resources LLC | Spring, TX 77381-5261-5261 | Oil & Gas Operator | Dec 2017 |
| 435 | Nea Cross Inc | Erie, PA 16508-2769 | Gas Operator | Dec 1991 |
| 436 | New Century Energy Inc | MC Donald, PA 15057-2163 | Oil & Gas Operator | Dec 2021 |
| 437 | New York Natural Gas Corp | Pittsburgh, PA 15222-1402 | Gas Operator | Dec 1990 |
| 438 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Apr 2024 |
| 439 | Norbert J Baumgart | Warren, PA 16365-3403 | Oil & Gas Operator | Dec 2009 |
| 440 | Nornew Inc | Houston, TX 77063-2140 | Oil & Gas Operator | Dec 2008 |
| 441 | North Amer Oil & Gas Drilling Co Inc | Pleasantville, PA 16341-0197 | Oil Operator | Dec 1999 |
| 442 | North Cambria Fuel Co | Blairsville, PA 15717-7961 | Gas Operator | Dec 2008 |
| 443 | North East Gas & Oil Co | Scottsville, VA 24590-3962 | Oil & Gas Operator | Dec 2013 |
| 444 | North John M | Valatie, NY 12184-5005 | Gas Operator | Dec 2014 |
| 445 | North Penn Gas Co | Allentown, PA 18101-1139 | Gas Operator | Dec 2000 |
| 446 | Northeast Natural Energy LLC | Charleston, WV 25301-2719 | Oil & Gas Operator | Jan 2024 |
| 447 | Northeastern Opr Co Inc | Shelocta, PA 15774-2346 | Gas Operator | Dec 2023 |
| 448 | Noumenon Corporation | Core, WV 26541-7072 | Oil & Gas Operator | Dec 2023 |
| 449 | NTS Energy LLC | Indiana, PA 15701-1801 | Oil & Gas Operator | Dec 2015 |
| 450 | Nucomer Energy LLC | Erie, PA 16507 | Oil & Gas Operator | Aug 2023 |
| 451 | Nytis Exploration Company LLC | Lexington, KY 40509 | Oil & Gas Operator | Dec 2021 |
| 452 | Oakes Gas Co Inc | Kane, PA 16735-3905 | Gas Operator | Dec 2019 |
| 453 | Oakmont CC | Oakmont, PA 15139-1135 | Gas Operator | Dec 2023 |
| 454 | Ohio Kentucky Oil Corporation | Lexington, KY 40503 | Oil & Gas Operator | Dec 2020 |
| 455 | Oil & Gas MGMT Inc | Mount Pleasant, PA 15666-3304 | Oil & Gas Operator | Dec 2021 |
| 456 | Oil & Gas SVC Inc | Reelsville, IN 46171-9686 | Gas Operator | Dec 1991 |
| 457 | Old MTN Gas Co Inc | Pleasantville, PA 16341-0329 | Oil & Gas Operator | Dec 2020 |
| 458 | Olympus Energy, LLC | Canonsburg, PA 15317 | Gas Operator | Jan 2024 |
| 459 | Olympus Prop Inc | Franklin Park, IL 60131-1418 | Oil & Gas Operator | Dec 1997 |
| 460 | Open Flow Gas Supply Corp | Du Bois, PA 15801-2442 | Oil & Gas Operator | Dec 2022 |
| 461 | Otter Exploration Inc | Warren, PA 16365-9689 | Oil & Gas Operator | Dec 2021 |
| 462 | Ows Acquisition Co LLC | Bolivar, OH 44612 | Oil & Gas Operator | Dec 2022 |
| 463 | Ows Energy LLC | Carlton, PA 16311-1605 | Oil & Gas Operator | Dec 2023 |
| 464 | Oz Gas LTD | Tidioute, PA 16351-2648 | Oil & Gas Operator | Dec 2016 |
| 465 | P & C Energy Co | Allegany, NY 14706-9615 | Oil Operator | Dec 2015 |
| 466 | Pa Dep Ofc Oil & Gas MGMT | Harrisburg, PA 17105-8765 | Gas Operator | Dec 1990 |
| 467 | Pa Gen Energy Co LLC | Warren, PA 16365-2510 | Oil & Gas Operator | Jan 2024 |
| 468 | Pa Gen Energy Corp | Warren, PA 16365-2510 | Oil & Gas Operator | Dec 2002 |
| 469 | Pa Land Holdings Corp | Waynesburg, PA 15370-3020 | Oil & Gas Operator | Dec 2011 |
| 470 | Pa Mineral SVCS LLC | Indiana, PA 15701 | Oil & Gas Operator | Dec 2023 |
| 471 | Pa Prod SVC Inc | Indiana, PA 15701-0421 | Oil & Gas Operator | Dec 2023 |
| 472 | Pa State Sys Of Higher Ed Indiana Univ | Indiana, PA 15705-0001 | Gas Operator | Dec 2012 |
| 473 | Papesch Robert J | Waterford, PA 16441-4607 | Gas Operator | Dec 2023 |
| 474 | Parker & Parsley Dev LP | Irving, TX 75039-3745 | Oil & Gas Operator | Mar 2015 |
| 475 | Patalon Robert E | Erie, PA 16505-0444 | Gas Operator | Dec 2023 |
| 476 | Patrick Shipley | Indiana, PA 15701-6501 | Oil & Gas Operator | Dec 2016 |
| 477 | Patriot Exploration Corp | Stahlstown, PA 15687-1301 | Oil & Gas Operator | Dec 2023 |
| 478 | Payne Frank | Shidler, OK 74652 | Oil & Gas Operator | Dec 2014 |
| 479 | PDC Mountaineer LLC | Bridgeport, WV 26330-9665 | Oil & Gas Operator | Dec 2017 |
| 480 | Peak Energy LLC | Coffeyville, KS 67337 | Oil & Gas Operator | Dec 2023 |
| 481 | Pecora Enterprises | Bradford, PA 16701-1026 | Oil & Gas Operator | Dec 1999 |
| 482 | Peggy J & Robert W Bell | Sheffield, PA 16347 | Oil & Gas Operator | Dec 2004 |
| 483 | Pembrooke Oil & Gas Inc | Franklin, PA 16323-7760 | Oil & Gas Operator | Dec 2020 |
| 484 | Pemco Gas Inc | Indian Harbor B, FL 32937 | Oil & Gas Operator | Dec 1997 |
| 485 | Penn VIew Exploration Inc | Blairsville, PA 15717-7961 | Oil & Gas Operator | Dec 2023 |
| 486 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2018 |
| 487 | Penneco Oil Company, Inc. | Delmont, PA 15626-2408 | Oil & Gas Operator | Dec 2023 |
| 488 | Pennenergy Resources LLC | Pittsburgh, PA 15275-1063-1063 | Oil & Gas Operator | Jan 2024 |
| 489 | Pennfield Energy LLC | Erie, PA 16510-4760 | Oil & Gas Operator | Dec 2021 |
| 490 | Pennhills Resources LLC | MT. Jewett, PA 16740 | Oil & Gas Operator | Jan 2024 |
| 491 | Pennzoil Prod Co | Vienna, WV 26105-2141 | Oil & Gas Operator | Dec 2000 |
| 492 | Pentex Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2003 |
| 493 | Peoples Gas Co LLC | Butler, PA 16001-4904 | Oil & Gas Operator | Dec 2005 |
| 494 | Petro Dev Corp | Bridgeport, WV 26330-0026 | Oil & Gas Operator | Dec 2013 |
| 495 | Petro North LTD | Smethport, PA 16749-0742 | Oil & Gas Operator | Dec 2023 |
| 496 | Petro SVC Partners Inc | Indiana, PA 15701-8556 | Oil & Gas Operator | Dec 2023 |
| 497 | Petro Ventures Inc | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2019 |
| 498 | Petrobank Opr Co | Denver, CO 80202-4675 | Gas Operator | Dec 1992 |
| 499 | PGH Univ | Pittsburgh, PA 15213-3203 | Gas Operator | Dec 2018 |
| 500 | Phillips Exploration Inc | Warrendale, PA 15086 | Oil & Gas Operator | Dec 2012 |