| 501 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 502 | Hurley Oil And Gas Company | | Oil & Gas Operator | Jan 1997 |
| 503 | Hurley Petroleum Corporation | Baton Rouge, LA 70821 | Oil & Gas Operator | Feb 2000 |
| 504 | Hutson Oil Co. | | Oil & Gas Operator | Nov 2024 |
| 505 | Hyman Muslow | | Oil Operator | Jun 1995 |
| 506 | I. W. McKnight,Production | | Oil Operator | Jan 1986 |
| 507 | Indian Exploration, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Oct 2025 |
| 508 | Indigo Haynesville LLC | | Gas Operator | Feb 2018 |
| 509 | Indigo Minerals LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2022 |
| 510 | Indigo Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2019 |
| 511 | Inland Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2025 |
| 512 | Inpetco, Inc. | | Oil & Gas Operator | Aug 1991 |
| 513 | Investco Oil And Gas Inc | | Oil & Gas Operator | Jan 2025 |
| 514 | J & A Oil Company | Odessa, TX 79764 | Oil & Gas Operator | Oct 2025 |
| 515 | J & B Service Co. | | Oil Operator | Nov 2024 |
| 516 | J & J Oil Company | Luling, TX 78648 | Oil & Gas Operator | Mar 2015 |
| 517 | J & L Oil Company | El Dorado, AR 71730 | Oil Operator | Jan 2025 |
| 518 | J & P Production | Holdenville, OK 74848-9485 | Oil Operator | Mar 2015 |
| 519 | J & S Production | | Oil Operator | Jan 2025 |
| 520 | J B Energy, Inc. | Denton, TX 76206 | Oil & Gas Operator | Aug 2018 |
| 521 | J D Baker | | Oil Operator | Oct 1999 |
| 522 | J D Briggs, Jr. | | Oil Operator | Mar 1993 |
| 523 | J F & G Production Company | | Oil & Gas Operator | Mar 1989 |
| 524 | J W Briggs Oil Company LLC | | Oil Operator | Sep 2013 |
| 525 | J&H Oil Company | Gainesville, TX 76240 | Oil & Gas Operator | Oct 2025 |
| 526 | J&V Oil Company | | Oil Operator | Dec 2024 |
| 527 | J-O'B Operating Company | Shreveport, LA 71135 | Oil & Gas Operator | Oct 2025 |
| 528 | J-W Gathering Company | | Oil Operator | Jun 2016 |
| 529 | J-W Operating Company | Christoval, TX 76935 | Oil & Gas Operator | Oct 2025 |
| 530 | J. C. Goodwill | | Oil & Gas Operator | Dec 2024 |
| 531 | J. C. Hoss | | Oil & Gas Operator | Oct 2024 |
| 532 | J. D. Briggs | | Oil Operator | Apr 1995 |
| 533 | J. D. Marcom | | Oil Operator | Sep 1989 |
| 534 | J. E. Hughes | | Oil & Gas Operator | Jan 1987 |
| 535 | J. E. Parker | | Oil Operator | Nov 1991 |
| 536 | J. F. Shelby Operating Agency | | Oil & Gas Operator | Nov 1986 |
| 537 | J. Kirin Oil & Gas LLC | | Oil Operator | Aug 2024 |
| 538 | J. P. Boyter | | Oil Operator | Dec 2024 |
| 539 | J. P. Boyter, Et Al | | Oil Operator | Jun 1993 |
| 540 | J. Pryor Lester, Jr. | | Oil Operator | Mar 1990 |
| 541 | J. V. Wynn | | Oil & Gas Operator | Dec 1991 |
| 542 | J. W. Bailey | | Oil Operator | Dec 1991 |
| 543 | J. W. Burton | | Oil & Gas Operator | Jul 1990 |
| 544 | J.P. Oil Company, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 545 | J.R. Oil Company | Houston, TX 77007 | Oil & Gas Operator | Jul 2019 |
| 546 | J.W. Briggs & W.B. Briggs | | Oil Operator | Jul 1994 |
| 547 | Jack Latham Co. | | Oil & Gas Operator | Jun 2018 |
| 548 | Jack W. Grigsby | | Oil & Gas Operator | Sep 2001 |
| 549 | Jackie D Nelson | | Oil & Gas Operator | Sep 1983 |
| 550 | Jackson Well Service | | Oil Operator | Apr 2001 |
| 551 | Jacky G. Rivers | | Oil & Gas Operator | Jan 2025 |
| 552 | James A Crowson, Jr | | Oil & Gas Operator | Jun 2010 |
| 553 | James A. Gibson | | Oil Operator | Dec 2002 |
| 554 | James C. Galbraith | | Oil & Gas Operator | Dec 1996 |
| 555 | James L Barber | | Oil Operator | Aug 1996 |
| 556 | James L. Boyter | | Oil Operator | Mar 1999 |
| 557 | James Marshall Jones | | Oil Operator | Sep 1997 |
| 558 | James P. Hardey | | Oil Operator | Jul 2003 |
| 559 | James R. McFarland | | Oil & Gas Operator | Jul 1997 |
| 560 | James W. Briggs | | Oil Operator | Aug 1999 |
| 561 | JD Oil Company | Longview, TX 75605 | Oil & Gas Operator | Sep 2014 |
| 562 | Jeems Bayou Production Corp. | Oil City, LA 71061 | Oil & Gas Operator | Oct 2025 |
| 563 | Jeffery Lynch Production | | Oil Operator | Jan 2025 |
| 564 | Jenkins Oil & Gas, Inc. | | Oil & Gas Operator | Aug 1992 |
| 565 | Jennings Oil Of VIvian LLC | | Oil Operator | Jan 2025 |
| 566 | Jim-Co Drilling Et Al | | Oil & Gas Operator | Mar 1991 |
| 567 | Jimmy P Dempsey | | Oil & Gas Operator | Jan 2025 |
| 568 | JLM Sartor Inc | | Oil & Gas Operator | Jul 2016 |
| 569 | Joe Lamar Oil, LLC | | Oil Operator | Jan 2025 |
| 570 | Joe M. Burnham | | Oil Operator | May 1993 |
| 571 | Joel B. Brown | | Oil & Gas Operator | Jan 1998 |
| 572 | John C. Bowers | | Oil & Gas Operator | Dec 1987 |
| 573 | John D. Caruthers, Jr. | | Oil & Gas Operator | Apr 1983 |
| 574 | John J. Welsh | | Oil & Gas Operator | Dec 2024 |
| 575 | John T. Weaver & Son | | Oil Operator | Jan 2025 |
| 576 | John W. McDowell | | Oil & Gas Operator | Aug 1991 |
| 577 | John W. Thomas | | Oil & Gas Operator | Jun 1993 |
| 578 | John W. Thomas, Jr. | | Oil Operator | Jun 1993 |
| 579 | Johnson'S Well Service | | Oil Operator | Jan 2004 |
| 580 | Jones Operating Company | Levelland, TX 79336 | Oil & Gas Operator | Oct 2000 |
| 581 | Jones-O'Brien, Inc. | | Oil & Gas Operator | Feb 1982 |
| 582 | Justiss Oil Company, Inc. | Jena, LA 71342 | Oil & Gas Operator | Jun 2025 |
| 583 | K & G Production | | Oil Operator | Jan 2025 |
| 584 | K & S Rentals | | Oil & Gas Operator | May 2013 |
| 585 | K & W Oil Company | MT Carmel, IL 62830 | Oil & Gas Operator | May 2013 |
| 586 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2025 |
| 587 | Kamlok, Inc. | | Oil Operator | Nov 1991 |
| 588 | Kanpetro, Inc. | | Oil Operator | May 1991 |
| 589 | KCS Resources LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 590 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 591 | Keith W. Burton | | Oil & Gas Operator | Jan 2025 |
| 592 | Kelley Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Jan 2002 |
| 593 | Kelly Bayou Production | | Oil & Gas Operator | Jan 2025 |
| 594 | Kennedy And Bacheller | | Oil & Gas Operator | Apr 1989 |
| 595 | Kenneth Darnell | | Oil Operator | Jan 2025 |
| 596 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | May 2025 |
| 597 | Key Energy Services, Inc.Altd | | Oil Operator | Dec 2006 |
| 598 | Key Energy Services, LLC | Houston, TX 77042 | Oil Operator | Jan 2025 |
| 599 | Key Operating Co., Inc. | Duncan, OK 73534-1284 | Oil & Gas Operator | Jan 2025 |
| 600 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jun 2025 |