| 2501 | Hallum Construction Inc | Seminole, OK 74868-2427 | Oil & Gas Operator | Sep 2014 |
| 2502 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2025 |
| 2503 | Ham Oil Company, LLC | | Oil Operator | Sep 2022 |
| 2504 | Hamil Oil & Gas LLC | Kingfisher, OK 73750-6500 | Oil & Gas Operator | Apr 2025 |
| 2505 | Hamilton B J | Ada, OK 74820-9404 | Oil & Gas Operator | Sep 1999 |
| 2506 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 2507 | Hamilton K M Oil & Gas Co | Ada, OK 74820 | Oil Operator | Jan 2013 |
| 2508 | Hammer Oil Properties Inc | Enid, OK 73706-0144 | Oil & Gas Operator | Oct 2017 |
| 2509 | Hammer Ranch | Elmore City, OK 73433 | Oil & Gas Operator | Jan 2023 |
| 2510 | Hamon Jake L | Dallas, TX 75201-3902 | Oil & Gas Operator | Nov 1997 |
| 2511 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 2512 | Hamp Oil | Ponca City, OK 74604 | Oil & Gas Operator | Sep 2002 |
| 2513 | Hampton Corporation (The) | Norman, OK 73069-5910 | Oil Operator | Jun 2016 |
| 2514 | Hancock Leon | Kingston, OK 73439-9618 | Oil Operator | Dec 2014 |
| 2515 | Hanna Oil And Gas Company | Fort Smith, AR 72901 | Oil & Gas Operator | Apr 2025 |
| 2516 | Hanoco Inc | Tulsa, OK 74135 | Oil & Gas Operator | Apr 2025 |
| 2517 | Hanover Operating Company | Tulsa, OK 74101 | Oil & Gas Operator | Dec 1998 |
| 2518 | Hansen Noel | Avant, OK 74001 | Oil Operator | Aug 2013 |
| 2519 | Happy Hill Operating LLC | Guthrie, OK 73044-7361 | Oil & Gas Operator | Oct 2017 |
| 2520 | Har-Ken Oil Co | | Oil & Gas Operator | Dec 2021 |
| 2521 | Harbert Energy Corp | Irving, TX 75015-2510 | Oil & Gas Operator | Feb 1993 |
| 2522 | Harbor Resources LLC | Oklahoma City, OK 73120 | Oil & Gas Operator | Jul 2025 |
| 2523 | Hard Rock Operating LLC | | Oil & Gas Operator | May 2022 |
| 2524 | Harden Operating Company Inc | Tulsa, OK 74106-2722 | Oil & Gas Operator | Sep 2006 |
| 2525 | Hardin Productions | Okemah, OK 74859 | Oil & Gas Operator | Dec 2006 |
| 2526 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Apr 2025 |
| 2527 | Harding And Shelton Exploration LLC | Oklahoma City, OK 73101-1557 | Oil & Gas Operator | Apr 2025 |
| 2528 | Harding Exploration, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2016 |
| 2529 | Hardwick Oil Company | Sugar Land, TX 77478 | Oil & Gas Operator | Nov 2014 |
| 2530 | Hargraves Elston | Ponca City, OK 74604 | Oil & Gas Operator | Jul 2003 |
| 2531 | Hargus Curtis | Macomb, OK 74852-8508 | Oil Operator | May 2017 |
| 2532 | Hargus Irrevocable Trust | Tecumseh, OK 74873-0590 | Oil Operator | Apr 2014 |
| 2533 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 2534 | Harlow Corporation, The | Amarillo, TX 79101 | Oil & Gas Operator | Apr 2014 |
| 2535 | Harmony Oil LLC | Cushing, OK 74023 | Oil Operator | Apr 2025 |
| 2536 | Harold G Raper Family Trust | Mansfield, TX 76063-1667 | Oil Operator | May 2023 |
| 2537 | Harold M Root Foundation | | Oil Operator | Apr 2025 |
| 2538 | Harp Peggy A | Seminole, OK 74868-2284 | Oil & Gas Operator | Mar 2024 |
| 2539 | Harper Joe Howard Dba J H Field Service | Nowata, OK 74048-9704 | Oil & Gas Operator | Dec 2024 |
| 2540 | Harrell Petroleum Inc | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Oct 2017 |
| 2541 | Harrell Verlan W | Oklahoma City, OK 73102-7201 | Oil & Gas Operator | Nov 1999 |
| 2542 | Harrington Billy B | Depew, OK 74028-3495 | Oil & Gas Operator | May 2006 |
| 2543 | Harrington Orville | Dewey, OK 74029 | Oil Operator | Apr 2025 |
| 2544 | Harrington SR Tommy W | Drumright, OK 74030-5778 | Oil Operator | May 2015 |
| 2545 | Harris B D | Norman, OK 73071-4802 | Oil & Gas Operator | Apr 2014 |
| 2546 | Harris Mildred C | Tulsa, OK 74120 | Oil & Gas Operator | Mar 2025 |
| 2547 | Harris Minerals Corp (The) | Oklahoma City, OK 73162-1045 | Oil & Gas Operator | Apr 2025 |
| 2548 | Harris Oil & Gas Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2016 |
| 2549 | Harris Olin | Okmulgee, OK 74447-8508 | Oil Operator | Feb 2012 |
| 2550 | Harrison Oil & Gas Inc | Houston, TX 77019 | Oil & Gas Operator | Jan 2025 |
| 2551 | Harrison-Wright Oil Company LLC | Tulsa, OK 74133-7035 | Oil & Gas Operator | May 2025 |
| 2552 | Harrod Leasing | Edmond, OK 73034 | Oil & Gas Operator | Apr 2025 |
| 2553 | Hart David | Chickasha, OK 73018-7756 | Oil & Gas Operator | Mar 2015 |
| 2554 | Harter Energy Inc. | Tulsa, OK 74105 | Oil & Gas Operator | May 2025 |
| 2555 | Hartline Tom | Drumright, OK 74030 | Oil Operator | Mar 2025 |
| 2556 | Hartman Oil Co., Inc. | Wichita, KS 67206 | Oil & Gas Operator | Mar 2025 |
| 2557 | Harvey A B | Seminole, OK 74868-1724 | Oil Operator | Mar 2015 |
| 2558 | Harwood Oil & Gas Inc | Greeley, CO 80631-8233 | Oil & Gas Operator | Apr 2025 |
| 2559 | Hat-Top Production Co | Duncan, OK 73533 | Oil Operator | Apr 2011 |
| 2560 | Hatley Delbert Jr Dba DH Enterprises | Oklahoma City, OK 73129 | Oil & Gas Operator | May 2025 |
| 2561 | Haught Harold | Hominy, OK 74035 | Oil Operator | Feb 2012 |
| 2562 | Hawkins & Hawkins | Council Hill, OK 74428 | Oil & Gas Operator | Jul 1996 |
| 2563 | Hawkins & Son Inc | Boynton, OK 74422 | Oil & Gas Operator | Aug 2019 |
| 2564 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 2565 | Hawthorne Carl A | Mounds, OK 74047-4936 | Oil & Gas Operator | Apr 2015 |
| 2566 | Haydens Oil And Gas LLC | Dover, OK 73734 | Oil & Gas Operator | Apr 2025 |
| 2567 | Hayes & Hudson | Bartlesville, OK 74003 | Oil & Gas Operator | Apr 2025 |
| 2568 | Haynes Jim L & Betty L | Haskell, OK 74436-8803 | Oil & Gas Operator | Dec 2013 |
| 2569 | Hays Herb E & K S | Bartlesville, OK 74006 | Oil Operator | Mar 2025 |
| 2570 | Hays Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2000 |
| 2571 | Hays Production LLC | Velma, OK 73491 | Oil & Gas Operator | May 2025 |
| 2572 | Hays Stanley L | Wynola, OK 74084 | Oil Operator | May 2022 |
| 2573 | Hazelwood Louis J | Albuquerque, NM 87111-6870 | Oil & Gas Operator | Feb 2023 |
| 2574 | Hazelwood Prod & Exp Co LLC | Oklahoma City, OK 73116-9037 | Oil & Gas Operator | Apr 2025 |
| 2575 | Hazen Oil Company | Cleveland, OK 74020-9633 | Oil Operator | Jul 2020 |
| 2576 | Hazlewood Oil & Gas Co Inc | Oklahoma City, OK 73139-9353 | Oil & Gas Operator | Apr 2022 |
| 2577 | HB Oil Company | Abilene, TX 79602 | Oil & Gas Operator | Jun 2023 |
| 2578 | HCG Energy Corporation & Subs | | Oil & Gas Operator | Mar 2015 |
| 2579 | HCL Inc | Woodward, OK 73802-1074 | Oil Operator | Mar 2015 |
| 2580 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 2581 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 2582 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 2583 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 2584 | Heartland Environmental Services | Watonga, OK 73080 | Oil & Gas Operator | May 1999 |
| 2585 | Heartland Exploration | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2000 |
| 2586 | Heartland Exploration Inc | Edmond, OK 73013 | Oil & Gas Operator | Dec 2015 |
| 2587 | Heartland Pumping | Hennessey, OK 73742-7311 | Oil & Gas Operator | Apr 2025 |
| 2588 | Heartlands Development Co Inc | Bristow, OK 74010-3826 | Oil & Gas Operator | May 2017 |
| 2589 | Heat Waves Hot Oil Service LLC | Denver, CO 80202 | Oil Operator | Jun 2011 |
| 2590 | Heath Jack A | Tulsa, OK 74132-2403 | Oil & Gas Operator | Jan 2013 |
| 2591 | Heath Oil Co., Inc. | Washington, OK 73093-4702 | Oil & Gas Operator | Apr 2025 |
| 2592 | Heaton Everill L | Exeter, CA 93221-2340 | Oil & Gas Operator | Sep 2014 |
| 2593 | Heights Energy Corporation | Plano, TX 75026 | Oil & Gas Operator | Jul 2025 |
| 2594 | Heinrich Production Co Inc | Lubbuck, TX 79424 | Oil Operator | Dec 2024 |
| 2595 | Helena Resources LLC | Helena, OK 73741 | Oil & Gas Operator | Apr 2025 |
| 2596 | Helke Exploration Company | Oklahoma City, OK 73112-7201 | Oil & Gas Operator | Feb 2000 |
| 2597 | Hellard Elmer J | Sapulpa, OK 74066 | Oil & Gas Operator | May 2025 |
| 2598 | Heller, Phillip & Charlene | Columbia, MO 65201 | Oil & Gas Operator | Mar 2025 |
| 2599 | Helmco LTD | Kiefer, OK 74041-0397 | Oil & Gas Operator | Jan 2007 |
| 2600 | Helmco Production Company | Pawhuska, OK 74056 | Oil Operator | Aug 2000 |