| 1501 | Aspen Exploration Corporation | | Oil & Gas Operator | Dec 2007 |
| 1502 | Aspen Exploration, Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2012 |
| 1503 | Aspen Land & Exploration Co | Tulsa, OK 74159-0335 | Oil & Gas Operator | Jul 2001 |
| 1504 | Aspen Oil & Gas LLC | | Oil Operator | Jul 2014 |
| 1505 | Aspen Oil Inc | Hobbs, NM 88241 | Oil & Gas Operator | Mar 2019 |
| 1506 | Aspen Operating Company LLC | Fort Worth, TX 76116 | Oil & Gas Operator | Sep 2026 |
| 1507 | Aspen Pumping Service | Artesia, NM 88211 | Oil & Gas Operator | Jan 2009 |
| 1508 | Asphalta LLC | | Oil & Gas Operator | Jul 2026 |
| 1509 | Aspire Exploration LLC | Cleveland, OK 74020-0727 | Oil & Gas Operator | Feb 2015 |
| 1510 | Asseff, George S Oil & Gas Company | | Oil & Gas Operator | Dec 2008 |
| 1511 | Assent Energy Partners, LLC | College Sta, TX 77842 | Oil & Gas Operator | Sep 2026 |
| 1512 | Asset Resources Inc | Mentor, OH 44060 | Oil & Gas Operator | Dec 2010 |
| 1513 | Assiduous Energy LLC | Edmond, OK 73034 | Oil & Gas Operator | Jul 2026 |
| 1514 | Assiniboine & Sioux Tribes | | Oil & Gas Operator | Mar 1997 |
| 1515 | Associated Natural Gas, Inc. | | Oil Operator | Apr 1996 |
| 1516 | Associated Oil & | | Oil Operator | Mar 1986 |
| 1517 | Associated Oil Properties | Agoura Hills, CA 91376 | Oil Operator | Nov 2020 |
| 1518 | Associated Petro | | Oil & Gas Operator | Aug 1994 |
| 1519 | Associated Petro Invest Inc | Stillwater, OK 74076-2346 | Oil & Gas Operator | May 2013 |
| 1520 | Associated Petroleum Consultants, Inc. | Wichita, KS 67202 | Gas Operator | Dec 2013 |
| 1521 | Astarta Springs Sustainable Farms LLC | | Oil & Gas Operator | Dec 2025 |
| 1522 | Astro Corporation | Tulsa, OK 74145 | Oil & Gas Operator | Apr 2007 |
| 1523 | Astro Energy Corporation | Edmond, OK 73083-3607 | Oil & Gas Operator | Sep 2014 |
| 1524 | At Oil & Gas, LLC | Eastland, TX 76448 | Oil & Gas Operator | Sep 2026 |
| 1525 | Atalaya Resources LLC | Tulsa, OK 74103-4361 | Oil & Gas Operator | Dec 2022 |
| 1526 | Atapco | Houston, TX 77040 | Oil & Gas Operator | Feb 1999 |
| 1527 | Atasca Resources, Inc. | Houston, TX 77219 | Oil & Gas Operator | Sep 2026 |
| 1528 | Atascosa Exploration, LLC | San Antonio, TX 78209 | Oil Operator | Apr 2020 |
| 1529 | Atc Realty Eight, Inc. | | Oil & Gas Operator | Nov 1988 |
| 1530 | Atchley Resources, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Jul 2026 |
| 1531 | Atco Prod. Co., Inc. | Winnie, TX 77665 | Oil & Gas Operator | Nov 2020 |
| 1532 | Atex Exploration & Operating Co. | Whitesboro, TX 76273 | Oil & Gas Operator | Sep 2026 |
| 1533 | Atf Petroleum Inc. | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 1534 | Atha Edward E | Athens, OH 45701 | Oil & Gas Operator | Dec 1987 |
| 1535 | Athabasca Energy Corporation | Simonton, TX 77476 | Oil & Gas Operator | Dec 2017 |
| 1536 | Athan Inc | Edmond, OK 73013-6628 | Oil & Gas Operator | Jul 2026 |
| 1537 | Athanor Texas Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2002 |
| 1538 | Athena Energy LLC | Toronto, ON M5E 1W7 | Gas Operator | Jan 2011 |
| 1539 | Athena Energy, Inc. | Gallatin, TN 37066 | Oil & Gas Operator | Sep 2026 |
| 1540 | Athena Resources, Inc. | Dallas, TX 75248 | Oil & Gas Operator | Sep 2026 |
| 1541 | Athlon Energy Operating LLC | Denver, CO 80202 | Oil & Gas Operator | Apr 2014 |
| 1542 | Athlon Fe Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2015 |
| 1543 | Athlon Holdings LP | Denver, CO 80202 | Oil & Gas Operator | Jan 2015 |
| 1544 | Atibara Operating, LLC | New Braunfels, TX 78130 | Oil Operator | Sep 2026 |
| 1545 | Atinum Energy, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jan 2014 |
| 1546 | Atinum Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2026 |
| 1547 | Atkins Oil L.C. | Conroe, TX 77303 | Oil Operator | Sep 2026 |
| 1548 | Atkins Production | | Oil Operator | Dec 2008 |
| 1549 | Atkinson Energy Corporation | Giddings, TX 78942 | Oil & Gas Operator | Jan 2010 |
| 1550 | Atkinson J V | Midland, TX 79702 | Oil & Gas Operator | Nov 2005 |
| 1551 | Atkinson Operations LLC | Three Rivers, TX 78071 | Oil Operator | Sep 2026 |
| 1552 | Atkinson WM H Estate | Oklahoma City, OK 73156 | Oil & Gas Operator | Nov 2001 |
| 1553 | Atkinson, Clifford III | San Antonio, TX 78217 | Oil & Gas Operator | Dec 1996 |
| 1554 | Atkinson, Jim | Nocona, TX 76255 | Oil & Gas Operator | Sep 2026 |
| 1555 | Atla Energy Inc | Zanesville, OH 43702-2607 | Oil & Gas Operator | Dec 2003 |
| 1556 | Atlanko Oil & Gas Inc | Tulsa, OK 74135-7846 | Oil & Gas Operator | Jun 2026 |
| 1557 | Atlanta Exploration Co. | | Oil & Gas Operator | Oct 2001 |
| 1558 | Atlantic & Gulf Petroleum Co. | Houston, TX 77002 | Gas Operator | Mar 1991 |
| 1559 | Atlantic Energy Corp Inc | Marietta, OH 45750 | Oil & Gas Operator | Dec 1991 |
| 1560 | Atlantic Exploration, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2015 |
| 1561 | Atlantic Oil Company | | Oil & Gas Operator | Dec 2025 |
| 1562 | Atlantic Operating II, LLC | Midland, TX 79702 | Oil & Gas Operator | Sep 2026 |
| 1563 | Atlantic Operating, Inc. | Midland, TX 79702 | Oil & Gas Operator | Feb 2015 |
| 1564 | Atlantic Petroleum Co. | | Oil Operator | Mar 2000 |
| 1565 | Atlantic Resources Company, LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 1566 | Atlantic Richfield Company | Houston, TX 77079 | Oil & Gas Operator | Dec 2016 |
| 1567 | Atlantis Oil Company, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Sep 2026 |
| 1568 | Atlantis Oil Cor | | Oil Operator | Sep 1989 |
| 1569 | Atlas Barnett, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2019 |
| 1570 | Atlas Eagle Ford Oper Co, LLC | Fort Worth, TX 76116 | Oil & Gas Operator | May 2020 |
| 1571 | Atlas Energy Corp | | Oil & Gas Operator | Nov 2005 |
| 1572 | Atlas Energy Corporation (Del.) | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 2026 |
| 1573 | Atlas Energy Group Inc | Uniontown, OH 44685-9575 | Oil & Gas Operator | Dec 2011 |
| 1574 | Atlas Fuel Supply, LTD. | Houston, TX 77269 | Oil Operator | Sep 2026 |
| 1575 | Atlas Growth Texas, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 2019 |
| 1576 | Atlas Noble LLC | Fort Worth, TX 76116-5423 | Oil & Gas Operator | Jun 2020 |
| 1577 | Atlas Oil & Gas Exploration, LLC | Cedar Park, TX 78613 | Oil & Gas Operator | Aug 2003 |
| 1578 | Atlas Oil Co, Inc | | Oil Operator | Dec 2023 |
| 1579 | Atlas Oil Company, LLC | Versailles, KY 40383 | Oil Operator | Dec 2023 |
| 1580 | Atlas Oil Exploration, Inc | | Oil & Gas Operator | Dec 1977 |
| 1581 | Atlas Oil Inc | Oklahoma City, OK 73154-0467 | Oil & Gas Operator | Aug 2008 |
| 1582 | Atlas Operating LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2026 |
| 1583 | Atlas Production Services | | Oil & Gas Operator | Feb 1999 |
| 1584 | Atlas Resources Inc | Coraopolis, PA 15108-0611 | Oil & Gas Operator | Dec 2007 |
| 1585 | Atlas Resources LLC | Pittsburgh, PA 15275-1033 | Oil & Gas Operator | Jun 2018 |
| 1586 | Atls Production Company LLC | Fort Worth, TX 76102-7426 | Gas Operator | Sep 2020 |
| 1587 | Atmic, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jun 2008 |
| 1588 | Atmos Pipeline - Texas | Dallas, TX 75240 | Oil & Gas Operator | Sep 2026 |
| 1589 | Atnipp, H. L. | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 1590 | Atoka Energy LLC | Gainesville, TX 76241 | Oil & Gas Operator | Sep 2026 |
| 1591 | Atoka Operating Permian, LLC | Addison, TX 75001 | Oil & Gas Operator | Sep 2023 |
| 1592 | Atoka Operating, Inc. | Gainesville, TX 76241 | Oil & Gas Operator | Sep 2026 |
| 1593 | Atp Oil & Gas Corporation | Houston, TX 77027 | Oil & Gas Operator | Jun 2008 |
| 1594 | Atropos Exploration Company | Dallas, TX 75225 | Oil & Gas Operator | Sep 2026 |
| 1595 | Atropos Production Corporation | Dallas, TX 75225 | Oil & Gas Operator | Sep 2026 |
| 1596 | Attaway Energy Group, Inc. | | Oil & Gas Operator | Aug 1995 |
| 1597 | Atteberry Engineering | Edmond, OK 73013-6624 | Oil & Gas Operator | Mar 2008 |
| 1598 | Attica Central School District | Attica, NY 14011 | Gas Operator | Dec 2025 |
| 1599 | Attica Gas Ventu | | Oil & Gas Operator | Dec 1995 |
| 1600 | Atwa Energy Co. | Breckenridge, TX 76424 | Oil & Gas Operator | Oct 1996 |