| 501 | Nordic Oil Company | | Oil & Gas Operator | Dec 1999 |
| 502 | Nordmeyer Oil, Inc. | Toronto, KS 66777 | Oil Operator | Dec 2019 |
| 503 | Nordstrand Engineering Inc | Houston, TX 77019 | Oil & Gas Operator | Feb 2026 |
| 504 | Nordstrand/Galoostian Oil & Gas | Houston, TX 77056 | Oil Operator | Mar 1998 |
| 505 | Norexco Inc. | | Oil & Gas Operator | Aug 1988 |
| 506 | Norgas Energy | Lakehills, TX 78063 | Oil & Gas Operator | Feb 2026 |
| 507 | Norman Brothers Tank Truck Inc | Pauls Valley, OK 73075 | Oil & Gas Operator | May 2020 |
| 508 | Norman Kenneth W | Sasakwa, OK 74867-0086 | Oil Operator | Oct 2017 |
| 509 | Norman L & Loretta E Gilbreath | Aztec, NM 87401 | Gas Operator | Aug 2018 |
| 510 | Norman L Gilbreath | Aztec, NM 87401 | Gas Operator | Aug 2018 |
| 511 | Norman Oil Corporation | Abilene, TX 79608 | Oil & Gas Operator | Mar 2000 |
| 512 | Norman Production Company | Chandler, OK 74834-8538 | Oil & Gas Operator | May 2015 |
| 513 | Norman, C. D. | Irving, TX 75015 | Oil & Gas Operator | Mar 2008 |
| 514 | Nornew Inc | Houston, TX 77063-2140 | Oil & Gas Operator | Dec 2008 |
| 515 | Norris, Robert E. III | Savannah, NY 13146 | Gas Operator | Dec 2024 |
| 516 | Norse Energy Corp USA | | Gas Operator | Dec 2011 |
| 517 | Norstar Development | Madras, OR 97741 | Oil Operator | Nov 2018 |
| 518 | Norstar Petroleu | | Oil & Gas Operator | Dec 1996 |
| 519 | Norstar Petroleum Inc | Englewood, CO 80112 | Oil & Gas Operator | Sep 2025 |
| 520 | Nortex Energy, Inc. | Muenster, TX 76252 | Oil Operator | Feb 2026 |
| 521 | Nortex Gas & Oil Co | Tulsa, OK 74135 | Oil & Gas Operator | Sep 1993 |
| 522 | Nortex Oil & Gas, Inc. | | Oil Operator | Feb 1994 |
| 523 | Nortex Production Co., LLC | Wichita Falls, TX 76310 | Oil Operator | Feb 2026 |
| 524 | North Amer Oil & Gas Drilling Co Inc | Pleasantville, PA 16341-0197 | Oil Operator | Dec 1999 |
| 525 | North Amer Oil Exp Inc | Trenton, OH 45067 | Oil Operator | Dec 2024 |
| 526 | North Amer Petroleum Inc | Zanesville, OH 43701 | Oil & Gas Operator | Dec 2000 |
| 527 | North American D | | Oil & Gas Operator | Sep 1986 |
| 528 | North American Drilling & Exploration, Inc. | Great Bend, KS 67530 | Oil & Gas Operator | Aug 2015 |
| 529 | North American Drilling Corp | Plano, TX 75093 | Oil & Gas Operator | Feb 2026 |
| 530 | North American Energy | | Oil & Gas Operator | Feb 1986 |
| 531 | North American Energy Inc | Duncan, OK 73533-9604 | Oil & Gas Operator | Nov 2000 |
| 532 | North American Exploration Co. | Abilene, TX 79602 | Oil & Gas Operator | Apr 1998 |
| 533 | North American Natural Crude In. | Houston, TX 77077 | Gas Operator | Mar 2019 |
| 534 | North American Operating, LLC | Ardmore, OK 73401 | Oil & Gas Operator | Dec 2025 |
| 535 | North American Petroleum Inc | Scottsdale, AZ 85262 | Oil & Gas Operator | Dec 2024 |
| 536 | North American Prod Co | Wooster, OH 44691 | Oil & Gas Operator | Dec 1998 |
| 537 | North American Reserve Corp. | Houston, TX 77060 | Oil & Gas Operator | Oct 2010 |
| 538 | North American Resources Company | Billings, MT 59101 | Oil & Gas Operator | Dec 2019 |
| 539 | North American Royalties, Inc. | Chattanooga, TN 37408 | Oil & Gas Operator | Oct 2001 |
| 540 | North American Technical Trading Company, Inc. | Oakbrook Terrace, IL 60181 | Oil Operator | Jan 2011 |
| 541 | North Bound Exploration Co | Pauls Valley, OK 73075-0863 | Oil & Gas Operator | Jan 2018 |
| 542 | North Cambria Fuel Co | Blairsville, PA 15717-7961 | Gas Operator | Dec 2008 |
| 543 | North Canadian Production LLC | Okemah, OK 74859 | Oil & Gas Operator | Nov 2025 |
| 544 | North Central Casing Puller Inc | Graham, TX 76450 | Oil & Gas Operator | Jan 1999 |
| 545 | North Central Casing Pullers,Inc | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 546 | North Central Drilling Co Inc | Mannford, OK 74044 | Oil & Gas Operator | May 2013 |
| 547 | North Central Oil Corp | Houston, TX 77252 | Oil & Gas Operator | Dec 2005 |
| 548 | North Central Oil Corp., Et Al | | Oil & Gas Operator | Mar 1977 |
| 549 | North Central Texas Energy LLC | Graham, TX 76450 | Oil & Gas Operator | Feb 2026 |
| 550 | North Coast Petroleum Inc | Hiram, OH 44234 | Oil & Gas Operator | Dec 1993 |
| 551 | North Country Energy LLC | Amarillo, TX 79159 | Oil & Gas Operator | Feb 2026 |
| 552 | North East Fuel Inc | Wooster, OH 44691 | Oil & Gas Operator | Dec 2015 |
| 553 | North East Gas & Oil Co | Scottsville, VA 24590-3962 | Oil & Gas Operator | Dec 2013 |
| 554 | North Finn LLC | Casper, WY 82605 | Oil & Gas Operator | Dec 2025 |
| 555 | North Fork Oil & Gas Inc | Brookville, PA 15825-7976 | Gas Operator | Dec 2005 |
| 556 | North Fork Operating LP | Mustang, OK 73064 | Oil & Gas Operator | Feb 2026 |
| 557 | North Harmony Ventures, Inc. | Jamestown, NY 14701 | Oil & Gas Operator | Dec 2024 |
| 558 | North John M | Valatie, NY 12184-5005 | Gas Operator | Dec 2014 |
| 559 | North Lake Resources LLC | Oklahoma City, OK 73132 | Oil & Gas Operator | Feb 2026 |
| 560 | North Lea Energy Co., LLC | Crossroads, NM 88114 | Oil & Gas Operator | Dec 2025 |
| 561 | North Of River Sanitary District | | Oil & Gas Operator | Dec 2002 |
| 562 | North Operating Company | Canton, TX 75103 | Oil & Gas Operator | Feb 2026 |
| 563 | North Pacific Oil And Gas, Inc | Houston, TX 77042 | Oil Operator | Mar 2013 |
| 564 | North Padre Explor. Venture LLC | Corpus Chrsti, TX 78473 | Oil & Gas Operator | May 2004 |
| 565 | North Penn Gas Co | Allentown, PA 18101-1139 | Gas Operator | Dec 2000 |
| 566 | North Plains Corp | Tulsa, OK 74137 | Oil & Gas Operator | Sep 2025 |
| 567 | North Plains Energy, LLC | | Oil & Gas Operator | Jan 2016 |
| 568 | North Plains Oil | | Oil Operator | Jul 1990 |
| 569 | North Range Resources, LLC | | Oil & Gas Operator | Nov 2023 |
| 570 | North Ridge Corporation | Duncanville, TX 75137 | Oil & Gas Operator | Feb 2026 |
| 571 | North Ridge Energy Inc | Rome, OH 44085-9713 | Oil & Gas Operator | Dec 2024 |
| 572 | North Shore Energy, L.L.C. | Austin, TX 78750 | Oil & Gas Operator | Feb 2026 |
| 573 | North Shore Exploration & Prod LLC | Broomfield, CO 80021 | Oil & Gas Operator | Dec 2025 |
| 574 | North Silo Resources LLC | Houston, TX 77055 | Oil & Gas Operator | Dec 2025 |
| 575 | North Slope Borough | | Gas Operator | Jan 2026 |
| 576 | North South Oil, LLC | Luling, TX 78648 | Oil Operator | Feb 2026 |
| 577 | North Star Energy Resources LLC | Waynesburg, PA 15370-3833 | Gas Operator | Dec 2024 |
| 578 | North Star Energy, Inc. | Strawn, TX 76475 | Oil & Gas Operator | Jan 2010 |
| 579 | North Star Exploration Company | Oklahoma City, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 580 | North Star Petroleum Corp. | San Antonio, TX 78209 | Oil & Gas Operator | Oct 1993 |
| 581 | North Texas Energy,Inc. | Dallas, TX 75252 | Oil Operator | Feb 2026 |
| 582 | North Texas Engineering | Midland, TX 79710 | Oil & Gas Operator | Nov 2002 |
| 583 | North Texas Llano Operating Corp | Dallas, TX 75225 | Oil & Gas Operator | Feb 2026 |
| 584 | North Texas Oil & Gas, LLC | Edmond, OK 73013 | Oil & Gas Operator | Feb 2026 |
| 585 | North Texas Plugging, LLC | Denton, TX 76205 | Oil & Gas Operator | Feb 2026 |
| 586 | North Texas Pure Gold, LLC | Graham, TX 76450 | Oil Operator | Sep 2008 |
| 587 | North Valley Gaswell Services | | Gas Operator | Nov 2025 |
| 588 | North Valley Oil & Gas Co. | | Oil & Gas Operator | Dec 1996 |
| 589 | Northam Oil Company Inc | Ada, OK 74820-3334 | Oil & Gas Operator | Feb 2025 |
| 590 | Northamerican Service Group | Katy, TX 77449 | Oil & Gas Operator | Feb 2026 |
| 591 | Northbrook Oil & Gas Co LLC | Norman, OK 73072 | Oil & Gas Operator | Nov 2014 |
| 592 | Northbrook Oil & Gas Company | Norman, OK 73070-4916 | Oil & Gas Operator | Jun 2016 |
| 593 | Northcoast Oil Company | | Oil & Gas Operator | Mar 2009 |
| 594 | Northcote Cleveland LLC | Borger, TX 79008 | Oil & Gas Operator | Nov 2025 |
| 595 | Northcott Exploration Co. Inc. | | Oil & Gas Operator | Dec 1987 |
| 596 | Northcutt Production | Bangs, TX 76823 | Oil & Gas Operator | Feb 2026 |
| 597 | Northeast Loop Gas Company, L.P. | Dallas, TX 75225 | Gas Operator | Jan 2003 |
| 598 | Northeast Natural Energy LLC | Charleston, WV 25301-2719 | Oil & Gas Operator | Dec 2025 |
| 599 | Northeast Production Co Inc | | Oil & Gas Operator | May 2013 |
| 600 | Northeast Resources | | Oil & Gas Operator | Jan 1992 |