| 401 | Hulen Operating Company | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 402 | Hulsey Larry O & Co | Graham, TX 76046 | Oil & Gas Operator | Jun 2012 |
| 403 | Hungerford Oil & Gas Inc | Helena, OK 73741 | Oil & Gas Operator | Nov 2000 |
| 404 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 405 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 406 | Hunton Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2025 |
| 407 | Husky Ventures Inc | Oklahoma City, OK 73134 | Oil & Gas Operator | Feb 2025 |
| 408 | Hux Oil Company LLC | Kingfisher, OK 73750 | Oil & Gas Operator | Mar 2025 |
| 409 | Hyalite Energy Corporation | Pampa, TX 79066 | Oil & Gas Operator | Feb 2025 |
| 410 | Impact Energy Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Mar 2025 |
| 411 | Inca Oil Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2009 |
| 412 | Indian Wells Oil Co | Oklahoma City, OK 73116 | Oil & Gas Operator | Jan 2000 |
| 413 | Inter-States Oil & Gas Inc | Edmond, OK 73003-0023 | Oil & Gas Operator | Apr 2020 |
| 414 | Internorth Inc | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2014 |
| 415 | Investment Equipment LLC | FT Morgan, CO 80701 | Oil & Gas Operator | Mar 2025 |
| 416 | Investors Resources Corp | Edmond, OK 73034 | Oil & Gas Operator | Mar 2025 |
| 417 | Itr Petroleum Inc | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 418 | J & S Of Enid Inc | Enid, OK 73701 | Oil & Gas Operator | Jul 2019 |
| 419 | J B Energy, Inc. | Denton, TX 76206 | Oil & Gas Operator | Aug 2018 |
| 420 | J L Hajek Enterprises LLC | Ames, OK 73718 | Oil & Gas Operator | Dec 2024 |
| 421 | Jackson L B Production Co | Tulsa, OK 74193-0001 | Oil & Gas Operator | Aug 2013 |
| 422 | Jai Oil | Lucien, OK 73757 | Oil & Gas Operator | Feb 2025 |
| 423 | James Lawrence E Estate Of | Crescent, OK 73028-9304 | Oil & Gas Operator | Nov 2021 |
| 424 | January Investments LLC | Norman, OK 73069-8224 | Oil & Gas Operator | Mar 2025 |
| 425 | Jay Management Company LLC | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 426 | Jay Petroleum Inc | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | Mar 2019 |
| 427 | Jay Resources Corporation | Houston, TX 77010 | Oil & Gas Operator | Feb 1998 |
| 428 | JB Petroleum Corporation | Purcell, OK 73080-6954 | Oil & Gas Operator | Sep 2018 |
| 429 | Jec Operating LLC | Oklahoma City, OK 73114-2717 | Oil & Gas Operator | Feb 2025 |
| 430 | Jefferson Co LLC (The) | Corinth, TX 76205 | Oil & Gas Operator | Aug 2004 |
| 431 | Jenkins Petroleum Inc | Stillwater, OK 74076 | Oil & Gas Operator | Mar 1994 |
| 432 | Jenkins Walter D | Oklahoma City, OK 73156-1022 | Oil & Gas Operator | Mar 2011 |
| 433 | Jerico Resources LLC | Seminole, OK 74868-6538 | Oil & Gas Operator | Apr 2020 |
| 434 | Jerry Sanner Oil Properties Inc | Enid, OK 73701 | Oil & Gas Operator | Mar 2025 |
| 435 | Jet Oil Co12/Ofb See 18649 | | Oil & Gas Operator | Jul 2007 |
| 436 | Jhatco Inc | Enid, OK 73701 | Oil & Gas Operator | Mar 2025 |
| 437 | JN Production LLP | Guthrie, OK 73028 | Oil & Gas Operator | Mar 2025 |
| 438 | Joe B Clifton Exploration Inc | Pauls Valley, OK 73075 | Oil & Gas Operator | Apr 2022 |
| 439 | Johnson Exploration Company | Oklahoma City, OK 73102-7008 | Oil & Gas Operator | Jun 2015 |
| 440 | Johnston Oil & Gas Inc | Bethany, OK 73008-5424 | Oil & Gas Operator | Sep 2009 |
| 441 | Jojon Petroleum Company | Dallas, TX 75219 | Oil & Gas Operator | Feb 2025 |
| 442 | Jones & Pellow Oil Co | Oklahoma City, OK 73118-1115 | Oil & Gas Operator | Feb 2015 |
| 443 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Feb 2025 |
| 444 | Jones, L. E. Production Co. | Duncan, OK 73534 | Oil & Gas Operator | Jul 2014 |
| 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 | Jan 2025 |
| 447 | K G Operating | Hennessey, OK 73742 | Oil & Gas Operator | May 1999 |
| 448 | K S Oil Company Inc | Norman, OK 73072-7480 | Oil & Gas Operator | Feb 2025 |
| 449 | Kahan And Associates, Inc | Tulsa, OK 74170 | Oil & Gas Operator | Feb 2025 |
| 450 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 451 | Kato Operating Company | Bristow, OK 74010 | Oil & Gas Operator | Mar 2015 |
| 452 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Feb 2025 |
| 453 | Keener Energy Company | Tulsa, OK 74103-4043 | Oil & Gas Operator | Jan 2014 |
| 454 | Kelloil Inc | Fort Worth, TX 76116-5600 | Oil & Gas Operator | Mar 2015 |
| 455 | Keno Oil & Gas Inc | Hennessey, OK 73742 | Oil & Gas Operator | Jan 1995 |
| 456 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 457 | Ketal Oil Producing Company | Fort Worth, TX 76102 | Gas Operator | Sep 1995 |
| 458 | Key Energy Corporation | Enid, OK 73702-5349 | Oil & Gas Operator | Oct 2017 |
| 459 | Kibtec Oil & Gas Inc | Cashion, OK 73016 | Oil & Gas Operator | Aug 2024 |
| 460 | Kingery Drilling Co., Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Mar 2025 |
| 461 | Kingfisher CSG Pullr & Const Inc | Hennessey, OK 73742-0024 | Oil & Gas Operator | Apr 2014 |
| 462 | Kirk David | Midland, TX 79705 | Oil & Gas Operator | Feb 2025 |
| 463 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 464 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | Mar 2025 |
| 465 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 466 | Koda Operating LLC | Tyler, TX 75703-5596 | Oil & Gas Operator | Feb 2025 |
| 467 | Kolar Petroleum Inc | Oklahoma City, OK 73162-1509 | Oil & Gas Operator | Jun 2007 |
| 468 | Kopco, Inc. | Caney, KS 67333 | Oil & Gas Operator | Mar 2025 |
| 469 | KPL Production Company LLC | Oklahoma City, OK 73112-4709 | Oil & Gas Operator | Feb 2017 |
| 470 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | Mar 2025 |
| 471 | Ladd Petroleum Corp. | Denver, CO 80202 | Oil & Gas Operator | Oct 2004 |
| 472 | Ladder Energy Company | Tulsa, OK 74120-4281 | Oil & Gas Operator | Jan 2018 |
| 473 | Lagoon Water Logistics LLC | Oklahoma City, OK 73103 | Oil Operator | Jul 2024 |
| 474 | Laguna Petroleum Corporation | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 475 | Lakeshore Operating, LLC | Wichita, KS 67203 | Oil & Gas Operator | May 2025 |
| 476 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Feb 2025 |
| 477 | Lammerts Robert P | Oklahoma City, OK 73102 | Oil & Gas Operator | Jan 2002 |
| 478 | Lancer Energy Corporation | Oklahoma City, OK 73132-5903 | Oil & Gas Operator | May 2015 |
| 479 | Landers & Musgrove | Okemah, OK 74859 | Oil & Gas Operator | Mar 2015 |
| 480 | Landers & Musgrove Oil Co. Inc | Okemah, OK 74859-0266 | Oil & Gas Operator | Jan 2018 |
| 481 | Landers & Waldman Inc | Okemah, OK 74859-0660 | Oil & Gas Operator | May 2013 |
| 482 | Laran Operating LLC | Dover, OK 73734-0057 | Oil & Gas Operator | Mar 2015 |
| 483 | Larkspur Operating LLC | Oklahoma City, OK 73034 | Oil & Gas Operator | Mar 2025 |
| 484 | Las Colinas Oil Corp. | Irving, TX 75062 | Oil & Gas Operator | Mar 2015 |
| 485 | Latigo Oil And Gas Inc | Woodward, OK 73801 | Oil & Gas Operator | Mar 2025 |
| 486 | Lawrence, C. F. & Assoc. Inc. | Lubbock, TX 79401 | Oil & Gas Operator | May 2025 |
| 487 | LCB Resources LLC | Kingfisher, OK 73750-2322 | Oil & Gas Operator | Mar 2025 |
| 488 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 489 | Leeman Don J | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 1998 |
| 490 | Legacy - M & K Corporation | Dallas, TX 75231-0969 | Oil & Gas Operator | Jan 2025 |
| 491 | Legacy Energy Services LLC | Stillwater, OK 74074 | Oil & Gas Operator | Mar 2025 |
| 492 | Legacy Reserves Operating LP | Denver, CO 80201 | Oil & Gas Operator | May 2025 |
| 493 | Lewbet Inc | Perry, OK 73077 | Oil & Gas Operator | Aug 2024 |
| 494 | Limestone Exploration II, LLC | Midland, TX 79704 | Oil & Gas Operator | Jun 2019 |
| 495 | Limestone Productions | Bartlesville, OK 74006-8229 | Oil & Gas Operator | Sep 2013 |
| 496 | Lincoln Ventures LLC | Inola, OK 74036-5035 | Oil & Gas Operator | Feb 2025 |
| 497 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 498 | Little Bear Resources LLC | Stillwater, OK 74074-1388 | Oil & Gas Operator | Feb 2013 |
| 499 | Little River Energy Company | Drumright, OK 74030 | Oil & Gas Operator | Mar 2025 |
| 500 | Littrell Chemical Inc | Cleo Springs, OK 73729 | Oil & Gas Operator | Jan 2005 |