| 401 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 402 | Hovas Enterprises | Perkins, OK 74059 | Oil & Gas Operator | Mar 2014 |
| 403 | HRC Production Co | Houston, TX 77002 | Oil & Gas Operator | Nov 2024 |
| 404 | Hulen Operating Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2025 |
| 405 | Hungerford Oil & Gas Inc | Helena, OK 73741 | Oil & Gas Operator | Nov 2000 |
| 406 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2025 |
| 407 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 408 | Hunton Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2025 |
| 409 | Husky Ventures Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Dec 2024 |
| 410 | Hux Oil Company LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Jan 2025 |
| 411 | Hyalite Energy Corporation | Pampa, TX 79066 | Oil & Gas Operator | Dec 2024 |
| 412 | I C Gas Amcana Inc | Tulsa, OK 74103-3713 | Oil & Gas Operator | Apr 1996 |
| 413 | Ike Energy LLC | Stillwater, OK 74074-1745 | Oil & Gas Operator | Dec 2024 |
| 414 | Inca Oil Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2009 |
| 415 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2025 |
| 416 | Infinity Hydrocarbons LLC | Houston, TX 77079 | Oil & Gas Operator | Aug 2022 |
| 417 | Intergy Production LLC | Edmond, OK 73083 | Oil & Gas Operator | Jan 2025 |
| 418 | Internorth Inc | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2014 |
| 419 | Investment Equipment LLC | FT Morgan, CO 80701 | Oil & Gas Operator | Jan 2025 |
| 420 | J & S Of Enid Inc | Enid, OK 73701 | Oil & Gas Operator | Jul 2019 |
| 421 | J & T Operating Inc | Norman, OK 73070-1736 | Oil & Gas Operator | Feb 2012 |
| 422 | J L Hajek Enterprises LLC | Ames, OK 73718 | Oil & Gas Operator | Dec 2024 |
| 423 | J O C Operating Inc | Fort Worth, TX 76102-6823 | Oil & Gas Operator | Feb 2021 |
| 424 | J O MC Oil & Gas Inc | Maud, OK 74854 | Oil & Gas Operator | Apr 1999 |
| 425 | Jaco, Troy Inc. | Sherman, TX 75091 | Oil & Gas Operator | Mar 2025 |
| 426 | James Larry | Guthrie, OK 73044-9622 | Oil & Gas Operator | Dec 2024 |
| 427 | James Lawrence E Estate Of | Crescent, OK 73028-9304 | Oil & Gas Operator | Nov 2021 |
| 428 | January Investments LLC | Norman, OK 73069-8224 | Oil & Gas Operator | Jan 2025 |
| 429 | Jay Petroleum Inc | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | Mar 2019 |
| 430 | Jayhawk Mineral Investments LLC | Edmond, OK 73034-8874 | Oil & Gas Operator | Dec 2024 |
| 431 | Jec Operating LLC | Oklahoma City, OK 73114-2717 | Oil & Gas Operator | Dec 2024 |
| 432 | Jegeroil Corp | New York, NY 10036 | Oil & Gas Operator | Aug 2000 |
| 433 | Jerry Sanner Oil Properties Inc | Enid, OK 73701 | Oil & Gas Operator | Jan 2025 |
| 434 | Jet Oil Co12/Ofb See 18649 | | Oil & Gas Operator | Jul 2007 |
| 435 | Jhatco Inc | Enid, OK 73701 | Oil & Gas Operator | Jan 2025 |
| 436 | JKB Resources LLC | Stigler, OK 74462 | Oil & Gas Operator | Dec 2024 |
| 437 | JMK Energy Company | Hennessey, OK 73742-0518 | Oil & Gas Operator | Jun 2016 |
| 438 | JN Production LLP | Guthrie, OK 73028 | Oil & Gas Operator | Jan 2025 |
| 439 | Johnson E Lyle | Oklahoma City, OK 73142 | Oil & Gas Operator | Dec 2024 |
| 440 | Johnson Exploration Company | Oklahoma City, OK 73102-7008 | Oil & Gas Operator | Jun 2015 |
| 441 | Johnson Oil Company | Duncan, OK 73533 | Oil Operator | Dec 2024 |
| 442 | Jojon Petroleum Company | Dallas, TX 75219 | Oil & Gas Operator | Dec 2024 |
| 443 | Jordan Oil & Gas Company | Healdsburg, CA 95448-1919 | Oil & Gas Operator | Mar 1995 |
| 444 | Jrhop Inc | Norman, OK 73072-4615 | Oil & Gas Operator | Dec 2015 |
| 445 | K & F Oil Co. | Olney, TX 76374 | Oil & Gas Operator | Dec 2021 |
| 446 | K & M Oil Company LLC | Hennessey, OK 73742 | Oil & Gas Operator | Dec 2024 |
| 447 | K S Oil Company Inc | Norman, OK 73072-7480 | Oil & Gas Operator | Dec 2024 |
| 448 | Kahan Louis | Tulsa, OK 74101 | Oil & Gas Operator | May 1994 |
| 449 | Kaiser Investments | Sand Springs, OK 74063 | Oil & Gas Operator | Sep 2003 |
| 450 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Mar 2025 |
| 451 | Kaneb Operating Company | Dallas, TX 75265-0283 | Oil & Gas Operator | Dec 1995 |
| 452 | Keener Energy Company | Tulsa, OK 74103-4043 | Oil & Gas Operator | Jan 2014 |
| 453 | Keener Oil & Gas Company | Tulsa, OK 74119-4416 | Oil & Gas Operator | Jan 2025 |
| 454 | Keener Oil Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2018 |
| 455 | Keith F. Walker Oil & Gas Co., LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jan 2025 |
| 456 | Kelle Day Oil Producers Inc | Braman, OK 74632-9147 | Oil & Gas Operator | Dec 2023 |
| 457 | Keno Oil & Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | Jan 1995 |
| 458 | Kepco. Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 459 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 460 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Jan 2025 |
| 461 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 462 | Key Energy Corporation | Enid, OK 73702-5349 | Oil & Gas Operator | Oct 2017 |
| 463 | Key Energy Services Inc | Midland, TX 79705-5540 | Oil Operator | Jan 2008 |
| 464 | Kibtec Oil & Gas Inc | Cashion, OK 73016 | Oil & Gas Operator | Aug 2024 |
| 465 | Kingfisher CSG Pullr & Const Inc | Hennessey, OK 73742-0024 | Oil & Gas Operator | Apr 2014 |
| 466 | Kingfisher Resources Inc | Clinton, OK 73601 | Oil & Gas Operator | Jan 2025 |
| 467 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Mar 2025 |
| 468 | Kirkpatrick Ronald B | | Oil & Gas Operator | Jul 2013 |
| 469 | Koby Oil Company LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2024 |
| 470 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 471 | Kodiak Oil & Gas Exploration Inc | Oklahoma City, OK 73134-1046 | Oil & Gas Operator | Dec 2024 |
| 472 | Kodiak Oil & Gas Inc | Muenster, TX 76252 | Oil & Gas Operator | Mar 2025 |
| 473 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2024 |
| 474 | L & N Exploration Inc | | Oil & Gas Operator | Jul 2013 |
| 475 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | Jan 2025 |
| 476 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Dec 2024 |
| 477 | Lance Ruffel Oil & Gas LLC | Oklahoma City, OK 73102-5632 | Oil & Gas Operator | Jan 2025 |
| 478 | Lancer Energy Corporation | Oklahoma City, OK 73132-5903 | Oil & Gas Operator | May 2015 |
| 479 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Mar 2025 |
| 480 | Las Colinas Oil Corp. | Irving, TX 75062 | Oil & Gas Operator | Mar 2015 |
| 481 | Laurel Operating Company, Inc. | Stillwater, OK 74074-3025 | Oil & Gas Operator | Jan 2025 |
| 482 | Lawrence James Oil Prop Inc | Catoosa, OK 74015 | Oil & Gas Operator | Feb 2012 |
| 483 | LCB Resources LLC | Kingfisher, OK 73750-2322 | Oil & Gas Operator | Jan 2025 |
| 484 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 485 | Leasehold Management Corp | Oklahoma City, OK 73170 | Oil & Gas Operator | Nov 2024 |
| 486 | Leeman Energy Corporation | Oklahoma City, OK 73118-1802 | Oil & Gas Operator | Mar 2015 |
| 487 | Legacy - M & K Corporation | Dallas, TX 75231-0969 | Oil & Gas Operator | Dec 2024 |
| 488 | Legacy Energy Services LLC | Stillwater, OK 74074 | Oil & Gas Operator | Jan 2025 |
| 489 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | Mar 2025 |
| 490 | Leigh Operating Co | Dallas, TX 75205 | Oil & Gas Operator | Mar 2008 |
| 491 | Lewis Oil Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Dec 2024 |
| 492 | Liberty Operating Inc | Norman, OK 73069-8225 | Oil & Gas Operator | Dec 2024 |
| 493 | Likins-Foster Honolulu Corp | Foster City, CA 94404 | Oil & Gas Operator | Feb 2015 |
| 494 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 495 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 496 | Lion Petroleum Company | Oklahoma City, OK 73120-4503 | Oil & Gas Operator | Aug 2015 |
| 497 | Little River Energy Company | Drumright, OK 74030 | Oil & Gas Operator | Dec 2024 |
| 498 | Littrell Chemical Inc | Cleo Springs, OK 73729 | Oil & Gas Operator | Jan 2005 |
| 499 | Lobar Oil Co LLC | Oklahoma City, OK 73116-1516 | Oil & Gas Operator | Dec 2024 |
| 500 | Lobo Energy, Inc. | Laredo, TX 78044 | Oil & Gas Operator | Nov 1996 |