| 1501 | Clark, Richard E., Inc. | Longview, TX 75604 | Oil & Gas Operator | May 2001 |
| 1502 | Clark, Robert A. | Wichita, KS 67202 | Gas Operator | Jul 1990 |
| 1503 | Clarkco Services, Inc. | | Oil & Gas Operator | Dec 2025 |
| 1504 | Clarke Corporati | Medicine Lodge, KS 67104 | Oil & Gas Operator | Feb 2026 |
| 1505 | Clarkston Oil Co | | Oil Operator | Dec 2025 |
| 1506 | Clarkston Oil Corp | | Oil Operator | Dec 2025 |
| 1507 | Claron Corporation | Houston, TX 77219 | Oil & Gas Operator | Jun 2026 |
| 1508 | Class Oil | Hays, KS 67601 | Oil Operator | Jun 1991 |
| 1509 | Class Petroleum Corporation | Barnsdall, OK 74002 | Oil Operator | Aug 2013 |
| 1510 | Classic Energy Incorporated | Tyler, TX 75701 | Oil & Gas Operator | Jul 2005 |
| 1511 | Classic Oil & Gas Resources Inc | | Gas Operator | Dec 2008 |
| 1512 | Classic Oil & Gas, Inc. | Tyler, TX 75701 | Oil & Gas Operator | Jan 2004 |
| 1513 | Classic Operating Co. LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 1514 | Classic Petroleum Partners, Inc. | Whitehouse, TX 75791 | Oil & Gas Operator | Jun 2026 |
| 1515 | Classic Well Service, Inc. | Claflin, KS 67525 | Oil Operator | Dec 2019 |
| 1516 | Claude Debeaux, Jr. Et Al | | Oil Operator | Dec 1999 |
| 1517 | Claude S. Hinds | | Oil Operator | Aug 1985 |
| 1518 | Claude-Maggie Co. | Midland, TX 79702 | Oil & Gas Operator | Jun 2026 |
| 1519 | Clausen, A. G. | Cross Plains, TX 76443 | Oil & Gas Operator | Jun 2026 |
| 1520 | Clausing, Garry | Coffeyville, KS 67337 | Oil Operator | Apr 2024 |
| 1521 | Claussen Roy A & | | Oil Operator | Jun 1986 |
| 1522 | Clavo Oil, LLC | Graham, TX 76450 | Oil & Gas Operator | Jun 2026 |
| 1523 | Clawson, Merle Eugene | McCune, KS 66753 | Oil Operator | Nov 2016 |
| 1524 | Clay A Muegge | | Oil & Gas Operator | Mar 2026 |
| 1525 | Clay Exploration, Inc. | Spring, TX 77387 | Oil & Gas Operator | Jun 2019 |
| 1526 | Clay Investments LLC | Stillwater, OK 74075-3600 | Oil & Gas Operator | Jan 2021 |
| 1527 | Clay Oil & Gas Co | Zanesville, OH 43701 | Oil Operator | Dec 1991 |
| 1528 | Clay Petroleum | Prosper, TX 75078 | Oil & Gas Operator | Feb 2023 |
| 1529 | Clay, Charles E. | Jacksboro, TX 76458 | Oil & Gas Operator | Sep 2010 |
| 1530 | Clay, Jerry H. | Tyler, TX 75702 | Oil & Gas Operator | Mar 2006 |
| 1531 | Claybanks Oil Co LLC | | Oil Operator | Jun 2019 |
| 1532 | Claybrook Drilling Co Inc | | Oil & Gas Operator | Sep 2014 |
| 1533 | Claybrook Production Co. Inc. | Wewoka, OK 74884-1380 | Oil & Gas Operator | Jun 2014 |
| 1534 | Clayton Corp Petro & Natural Gas Prod | Lakewood, CO 80228-1836 | Oil & Gas Operator | Oct 2020 |
| 1535 | Clayton Corp Petro & NTRL Gas Prodn | Lakewood, CO 80228 | Oil & Gas Operator | Dec 2009 |
| 1536 | Clayton Corporation | Golden, CO 80401 | Oil & Gas Operator | Dec 2019 |
| 1537 | Clayton Investment | Farmington, NM 87401 | Oil & Gas Operator | Jun 1995 |
| 1538 | Clayton Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | May 2004 |
| 1539 | Clayton W. Williams, Jr. | | Oil & Gas Operator | Sep 1986 |
| 1540 | Clayton W. Williams, Jr., Inc. | | Oil & Gas Operator | May 1993 |
| 1541 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 1542 | CLC Operations Inc | Midland, TX 79701 | Oil & Gas Operator | Mar 1997 |
| 1543 | Clean Energy Exploration & Production LLC | Norristown, PA 19403 | Gas Operator | Mar 2026 |
| 1544 | Clean Energy Systems Placerita Inc. | | Oil & Gas Operator | Dec 2025 |
| 1545 | Clean Gas, Inc | Hindman, KY 41822 | Oil & Gas Operator | Dec 2023 |
| 1546 | Clean Oil LLC | Ada, OK 74820 | Oil & Gas Operator | Dec 2025 |
| 1547 | Cleantex Oilfield Services, LLC | Tyler, TX 75702 | Oil Operator | Jun 2026 |
| 1548 | Clear Brooke Ranches, LLC | Fort Worth, TX 76179 | Oil & Gas Operator | Jun 2026 |
| 1549 | Clear Creek Energy LLC | | Oil & Gas Operator | Dec 2021 |
| 1550 | Clear Creek Exploration LLC | Fredonia, KS 66736 | Gas Operator | Apr 2011 |
| 1551 | Clear Creek Oil Co | Nova, OH 44859 | Oil & Gas Operator | Dec 2018 |
| 1552 | Clear Creek Royalty LLC | Tulsa, OK 74137 | Oil & Gas Operator | Jul 2023 |
| 1553 | Clear Fork Gas Company | Albany, TX 76430 | Oil & Gas Operator | Jun 2026 |
| 1554 | Clear Fork, Incorporated | Abilene, TX 79604 | Oil & Gas Operator | Jun 2026 |
| 1555 | Clear Lake Oil Co. | | Oil Operator | Jan 2025 |
| 1556 | Clear Water Inc. | Midland, TX 79710 | Oil & Gas Operator | Jun 2026 |
| 1557 | Clearfield Energy Resources & Management Inc. | | Oil & Gas Operator | Dec 1998 |
| 1558 | Clearfork Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 2011 |
| 1559 | Clearfork Petroleum Inc. (A) | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2026 |
| 1560 | Clearfork Production, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2018 |
| 1561 | Clearly Petroleum, LLC | Houston, TX 77086 | Oil & Gas Operator | Jun 2020 |
| 1562 | Cleary Exploration LLC | Oklahoma City, OK 73112-7221 | Oil & Gas Operator | Oct 2014 |
| 1563 | Cleary Jo Anne | Saint Louis, OK 74866 | Oil Operator | Mar 2026 |
| 1564 | Cleary Petroleum Corporation | Edmond, OK 73083 | Oil & Gas Operator | Jul 2019 |
| 1565 | Cleaver Loraine | | Oil Operator | Dec 1996 |
| 1566 | Cleaver, Loraine G. (Deceased) Estate | Iola, KS 66749 | Oil Operator | Nov 2009 |
| 1567 | Cleere Operating LLC | Shawnee, OK 74804-2610 | Oil Operator | Feb 2026 |
| 1568 | Clem Energy LLC | | Oil & Gas Operator | Dec 2021 |
| 1569 | Clements Energy, Inc. | | Oil & Gas Operator | Oct 1987 |
| 1570 | Clements Exploration Co | Oklahoma City, OK 73132-5922 | Oil & Gas Operator | Jan 2006 |
| 1571 | Clements Operating Company, Inc. | Luling, TX 78648 | Oil & Gas Operator | Aug 2003 |
| 1572 | Clements-B & MCK - Luffey | | Gas Operator | Apr 1979 |
| 1573 | Clemishire Don | Hominy, OK 74035 | Oil & Gas Operator | Mar 2026 |
| 1574 | Clemishire, Brian S | | Oil & Gas Operator | Nov 2014 |
| 1575 | Clemishire, Jerry L | | Oil & Gas Operator | Mar 2026 |
| 1576 | Clemishire, Mark E | | Oil Operator | Mar 2026 |
| 1577 | Clemons, Tony W. | Minden, LA 71055 | Oil & Gas Operator | Dec 2016 |
| 1578 | Clemshire Bob | Hominy, OK 74035 | Oil & Gas Operator | Feb 2026 |
| 1579 | Clemshire Drilling Company | Tulsa, OK 74105 | Oil Operator | Feb 2026 |
| 1580 | Clendening, John A | | Oil Operator | Dec 2021 |
| 1581 | Cleo Oil, Inc. | Olney, TX 76374 | Oil & Gas Operator | May 1997 |
| 1582 | Cleveland Oil & Gas | Wichita Falls, TX 76308 | Oil Operator | Jun 2026 |
| 1583 | Cleveland Oil Company,L.L.C.,The | Midland, TX 79702 | Oil & Gas Operator | Sep 1999 |
| 1584 | Cleveland Production Company | Summit, MS 39666 | Oil & Gas Operator | Jul 1999 |
| 1585 | Cleveland Rod & Tracy | Elmore City, OK 73433-9467 | Oil & Gas Operator | Jul 2023 |
| 1586 | Click Betty | Stigler, OK 74462-0081 | Oil & Gas Operator | Feb 2016 |
| 1587 | Click Corp | Monroe, LA 71207 | Oil & Gas Operator | Jan 2025 |
| 1588 | Click Energy Company | Houston, TX 77269 | Oil & Gas Operator | Jun 2026 |
| 1589 | Click Robert R | Dallas, TX 75231 | Oil & Gas Operator | Nov 1995 |
| 1590 | Clide Oil Corp. | Iraan, TX 79744 | Oil & Gas Operator | Nov 2015 |
| 1591 | Clifford & Scott McKeever | Clarksburg, PA 15725 | Gas Operator | Dec 2024 |
| 1592 | Clifford C. Or Mary A. Terry | Dadeville, AL 36853 | Oil Operator | Feb 2003 |
| 1593 | Cliffs Drilling Company | | Oil & Gas Operator | Dec 1984 |
| 1594 | Cliffs Oil And Gas Company | | Oil & Gas Operator | Oct 1997 |
| 1595 | Cliffwood Production Co. | Houston, TX 77090 | Oil & Gas Operator | Aug 2013 |
| 1596 | Clift Cary E | Chickasha, OK 73018-6305 | Oil & Gas Operator | Jun 2025 |
| 1597 | Clifton & Associates Inc | Tulsa, OK 74133 | Oil & Gas Operator | May 2020 |
| 1598 | Clifton Consulting Inc | Piedmont, OK 73078-0180 | Gas Operator | Feb 2026 |
| 1599 | Clifton Oil | Muenster, TX 76252 | Oil & Gas Operator | Mar 2006 |
| 1600 | Clifton, B.W. | Graham, TX 76450 | Oil & Gas Operator | Mar 2000 |