| 401 | Marathon Oil Company | Houston, TX 77252 | Oil & Gas Operator | Nov 2025 |
| 402 | Marks & Co., Inc. | | Oil & Gas Operator | Dec 2021 |
| 403 | Marsh Operating Company | Dallas, TX 75221 | Oil & Gas Operator | Sep 2025 |
| 404 | Marshall, Dale | | Gas Operator | Dec 1995 |
| 405 | Massey Group, Inc. | | Oil & Gas Operator | Dec 2004 |
| 406 | May Gas, Inc. | | Oil & Gas Operator | Dec 2008 |
| 407 | McCarty, Charles E | Spencer, WV 25276 | Oil & Gas Operator | Dec 2021 |
| 408 | McCullough, Richard F. | Pennsboro, WV 26415 | Oil & Gas Operator | Dec 2021 |
| 409 | MCF Co. | | Oil & Gas Operator | Dec 2011 |
| 410 | McIntosh Oil & Gas, Inc. | Coalton, WV 26257 | Oil & Gas Operator | Dec 2021 |
| 411 | McRain Petroleum | Weston, WV 26452-0000 | Oil & Gas Operator | Dec 2020 |
| 412 | Meadow Ridge Development, LLC | Washington, PA 15301 | Oil & Gas Operator | Dec 2021 |
| 413 | Meadows Jr, S. L. Production Inc. | Ravenswood, WV 26164-0022 | Oil & Gas Operator | Dec 2021 |
| 414 | Megaenergy Operating, Inc. | Edmond, OK 73034 | Oil & Gas Operator | Jul 2015 |
| 415 | Megan Oil & Gas Co., Inc. | Spencer, WV 25276-0000 | Oil & Gas Operator | Dec 2021 |
| 416 | Meridian Exploration Corp. | Pittsburgh, PA 15222 | Oil & Gas Operator | Dec 2021 |
| 417 | Mert Development Inc | | Oil & Gas Operator | Dec 2021 |
| 418 | Mid-Eastern Oil & Gas Co. | Burton, WV 26562-0000 | Oil & Gas Operator | Dec 2021 |
| 419 | Mid-Penn Energy Corporation | Harrisburg, PA 17101-1002 | Gas Operator | Dec 2021 |
| 420 | Midway City Gas Company | Huntington, WV 25701 | Oil & Gas Operator | Dec 2018 |
| 421 | Miller, Allerton | | Oil & Gas Operator | Dec 1997 |
| 422 | Mills Drilling Co Inc | | Oil & Gas Operator | Nov 2008 |
| 423 | Milton Oil & Gas Company | Charleston, WV 25322 | Gas Operator | Nov 1997 |
| 424 | Mineral Resource Management, L.L.C. | Jane Lew, WV 26378 | Oil & Gas Operator | Dec 2021 |
| 425 | MLX Operating, Inc. | Bridgeport, WV 26330 | Oil & Gas Operator | Dec 2021 |
| 426 | Monge Oil Corp. | | Oil & Gas Operator | Dec 2021 |
| 427 | Moody Oil & Gas Co. | Bridgeport, WV 26330-1051 | Oil & Gas Operator | Dec 2004 |
| 428 | Morris Beall Oil & Gas Co | | Oil & Gas Operator | Dec 2021 |
| 429 | Morris Oil & Gas Co., Inc | | Oil & Gas Operator | Dec 2021 |
| 430 | Morris, Carl R | | Oil & Gas Operator | Dec 2015 |
| 431 | Moses Gas, Inc. | Indore, WV 25111-0100 | Gas Operator | Dec 2018 |
| 432 | Mossor, L. E. | Harrisville, WV 26362-0000 | Oil & Gas Operator | Dec 2002 |
| 433 | Motto Energy Inc. | Normantown, WV 25267-8215 | Oil & Gas Operator | Dec 2021 |
| 434 | Mountain State Oil Company, L..L.C. | Pennsboro, WV 26415-0014 | Oil & Gas Operator | Dec 2021 |
| 435 | Mountain State Well Tending | Hurricane, WV 25526-0000 | Oil & Gas Operator | Dec 2021 |
| 436 | Mountain V Oil & Gas, Inc. | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 437 | Mountain V, LLC | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 438 | Mountaineer Gas Transmission, Inc. | Fort Worth, TX 76185-0000 | Oil & Gas Operator | Dec 2021 |
| 439 | Mountaineer Oil & Gas, LLC | | Oil & Gas Operator | Dec 2020 |
| 440 | Mountaineer State Energy, Inc. | Dallas, TX 75234 | Oil & Gas Operator | Dec 2021 |
| 441 | Mountaineer State Operations, LLC | Sandyville, WV 25275 | Oil & Gas Operator | Dec 2024 |
| 442 | Mountaineer Trading Company, LLC | Charleston, WV 25314 | Oil & Gas Operator | Dec 2016 |
| 443 | Mullen Resources LLC | Reedy, WV 25270 | Oil & Gas Operator | Dec 2021 |
| 444 | Mumma Oil Production Co., Inc. | Allentown, PA 18109-0000 | Oil & Gas Operator | Dec 2019 |
| 445 | Murray Hill Energy, Inc. | Bridgeport, WV 26330 | Oil & Gas Operator | Dec 2017 |
| 446 | Murvin & Meier Oil Co. | | Oil & Gas Operator | Dec 2020 |
| 447 | Mutschelknaus, Clarence W | Salem, WV 26426-0351 | Oil & Gas Operator | Dec 2021 |
| 448 | Mutual Oil & Gas Co | Akron, OH 44311 | Oil & Gas Operator | Dec 2000 |
| 449 | Myers Drilling Company | Barboursville, WV 25504 | Oil & Gas Operator | Dec 2024 |
| 450 | Nanco Resources, LLC | | Gas Operator | Dec 2021 |
| 451 | Nashville Associates Inc | | Oil & Gas Operator | Dec 2003 |
| 452 | NCL Natural Resources LLC | Spring, TX 77381-5261 | Oil & Gas Operator | Dec 2017 |
| 453 | Nesler, Charles E. | | Oil & Gas Operator | Dec 2020 |
| 454 | New River Energy Corporation | | Gas Operator | Dec 2017 |
| 455 | Night Owl Well Service | Cairo, WV 26337-0000 | Oil & Gas Operator | Dec 2021 |
| 456 | Nitro Energy, Inc. | | Gas Operator | Dec 2005 |
| 457 | Noble Energy Inc | Midland, TX 79706 | Oil & Gas Operator | Dec 2025 |
| 458 | Northeast Natural Energy LLC | Charleston, WV 25301-2719 | Oil & Gas Operator | Nov 2025 |
| 459 | Northport Production Company | Oklahoma City, OK 73113 | Oil & Gas Operator | Oct 2025 |
| 460 | Northstar Energy Corporation | Charleston, WV 25337-0000 | Oil & Gas Operator | Dec 2021 |
| 461 | Norwes Industries, Inc. | | Oil & Gas Operator | Jun 2000 |
| 462 | Noumenon Corporation | Core, WV 26541-7072 | Oil & Gas Operator | Dec 2024 |
| 463 | Nytis Exploration Company LLC | Lexington, KY 40509 | Oil & Gas Operator | Dec 2021 |
| 464 | Odyssey Petroleum, Inc. | Overland Park, KS 66282 | Oil & Gas Operator | Apr 2009 |
| 465 | Ohio L & M Company Inc | Marietta, OH 45750 | Oil & Gas Operator | Dec 2008 |
| 466 | Oil Rock Oil Company, Inc. | Elizabeth, WV 26143 | Oil & Gas Operator | Dec 2021 |
| 467 | Oiltex, Inc. | Baltimore, MD 21221 | Oil & Gas Operator | Dec 2013 |
| 468 | Okmar Oil Company | Marietta, OH 45750 | Oil & Gas Operator | Jun 2005 |
| 469 | Operator Unknown | Charleston, WV 25304-0000 | Oil & Gas Operator | Dec 2021 |
| 470 | Ows Acquisition Co LLC | Louisville, OH 44641 | Oil & Gas Operator | Dec 2024 |
| 471 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Dec 2025 |
| 472 | P & C Oil & Gas, Inc. | Linn, WV 26384 | Oil & Gas Operator | Dec 2021 |
| 473 | P & M Oil Company | Hays, KS 67601 | Oil & Gas Operator | Oct 2025 |
| 474 | P & S Oil And Gas Corporation | | Gas Operator | Dec 1996 |
| 475 | P. D. L. Services, Inc. | Minerva, OH 44657 | Oil & Gas Operator | Dec 2024 |
| 476 | P. G. Oil & Gas, LLC | Clarksburg, WV 26302-2512 | Oil & Gas Operator | Dec 2021 |
| 477 | Pacific Atlantic Resources, Inc. | | Oil & Gas Operator | Dec 2021 |
| 478 | Paleo, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Dec 2025 |
| 479 | Parker Gas Company | | Oil & Gas Operator | Aug 2020 |
| 480 | Parker, Denzil L & Emma Louise | Mannington, WV 26582-0188 | Oil & Gas Operator | Dec 2016 |
| 481 | Parks, Lawrence E | Big Bend, WV 26136-0000 | Oil & Gas Operator | Nov 2013 |
| 482 | Patchwork Oil & Gas LLC | Davisville, WV 26142 | Oil & Gas Operator | Dec 2021 |
| 483 | Pauley, Joseph E | Spencer, WV 25276-8719 | Oil & Gas Operator | Dec 2021 |
| 484 | Pauley, Ralph | Sod, WV 25564 | Oil & Gas Operator | Dec 2021 |
| 485 | Paulico Resources, Inc. | Charleston, WV 25301-0000 | Oil & Gas Operator | Dec 2021 |
| 486 | Payne, Robert E | Buckhannon, WV 26201 | Oil & Gas Operator | Dec 2021 |
| 487 | PDC Mountaineer LLC | Bridgeport, WV 26330-9665 | Oil & Gas Operator | Dec 2017 |
| 488 | Peake Operating Company | | Oil & Gas Operator | Dec 1999 |
| 489 | Pemco Gas Inc | Indian Harbor B, FL 32937 | Oil & Gas Operator | Dec 1997 |
| 490 | Penn VIrginia Oil & Gas Corp | Houston, TX 77024 | Oil & Gas Operator | Dec 2023 |
| 491 | Penn-Ohio Investment Corp. | New Philadelphi, OH 44663 | Oil & Gas Operator | Dec 2004 |
| 492 | Penneco Oil Company, Inc. | Delmont, PA 15626-2408 | Oil & Gas Operator | Dec 2024 |
| 493 | Pentex Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2003 |
| 494 | Pentress Gas LLC | Pentress, WV 26544 | Gas Operator | Dec 2021 |
| 495 | Pepper Development, LLC | Clarksburg, WV 26302 | Oil & Gas Operator | Dec 2021 |
| 496 | Perkins Oil & Gas Inc | Pennsboro, WV 26415-0547 | Oil & Gas Operator | Dec 2021 |
| 497 | Perkins Production Company LLC | Pennsboro, WV 26415 | Oil & Gas Operator | Dec 2021 |
| 498 | Pethtel Oil & Gas | | Oil & Gas Operator | Dec 2005 |
| 499 | Petro Holdings, Inc. | Spencer, WV 25276-0000 | Oil & Gas Operator | Dec 2021 |
| 500 | Petro-Go, Inc. | | Oil & Gas Operator | Mar 1996 |