| 401 | J & J Oil Company | Luling, TX 78648 | Oil & Gas Operator | Mar 2015 |
| 402 | J & J Oil Company LLC | Lubbock, TX 79424 | Oil Operator | Oct 2025 |
| 403 | J-Tag Public Saltwater | Healtdon, OK 73438 | Oil Operator | Sep 1998 |
| 404 | Jackson, Jeral W. Inc. | Wichita Falls, TX 76307 | Oil & Gas Operator | May 2004 |
| 405 | Jan Oil Company | Oklahoma City, OK 73156 | Oil & Gas Operator | May 2006 |
| 406 | January Investments LLC | Norman, OK 73069-8224 | Oil & Gas Operator | Jul 2025 |
| 407 | Jaquess W D "Bud" | Ada, OK 74820 | Oil & Gas Operator | Jan 2018 |
| 408 | Jasmine Inc | Duncan, OK 73534-1103 | Oil & Gas Operator | Jun 2017 |
| 409 | Jay B Harden | | Oil Operator | Jun 2025 |
| 410 | Jay Petroleum Inc | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | Mar 2019 |
| 411 | JCT #1 LTD | Fairview, OK 73737-9614 | Oil Operator | Sep 2006 |
| 412 | Jec Operating LLC | Oklahoma City, OK 73114-2717 | Oil & Gas Operator | Jun 2025 |
| 413 | Jerico Resources LLC | Seminole, OK 74868-6538 | Oil & Gas Operator | Apr 2020 |
| 414 | Jerry Sanner Oil Properties Inc | Enid, OK 73701 | Oil & Gas Operator | Jul 2025 |
| 415 | Jerry Scott Drilling Company Inc | Ada, OK 74821 | Oil & Gas Operator | Apr 2025 |
| 416 | Jet Oil Co12/Ofb See 18649 | | Oil & Gas Operator | Jul 2007 |
| 417 | Jetson Operating Inc | Ada, OK 74820 | Oil & Gas Operator | Sep 2024 |
| 418 | Jimmy R Chatham LLC | Healdton, OK 73438 | Oil & Gas Operator | Jul 2025 |
| 419 | Joe B Clifton Exploration Inc | Pauls Valley, OK 73075 | Oil & Gas Operator | Apr 2022 |
| 420 | Johnson Exploration Company | Oklahoma City, OK 73102-7008 | Oil & Gas Operator | Jun 2015 |
| 421 | Jolen Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2025 |
| 422 | Jones & Pellow Oil Co | Oklahoma City, OK 73118-1115 | Oil & Gas Operator | Feb 2015 |
| 423 | Jones Babe Inc | Floydada, TX 79235-0180 | Oil & Gas Operator | May 2019 |
| 424 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2025 |
| 425 | Jones III Thomas J | Duncan, OK 73533-4995 | Oil & Gas Operator | Dec 2018 |
| 426 | Jones Oil Company LLC (The) | Duncan, OK 73533-4995 | Oil & Gas Operator | Mar 2025 |
| 427 | Jones, L. E. Production Co. | Duncan, OK 73534 | Oil & Gas Operator | Jul 2014 |
| 428 | Jubilee Exploration LLC | Ardmore, OK 73401-7526 | Oil & Gas Operator | Dec 2024 |
| 429 | K & F Oil Co. | Olney, TX 76374 | Oil & Gas Operator | Dec 2021 |
| 430 | K S Oil Company Inc | Norman, OK 73072-7480 | Oil & Gas Operator | Jun 2025 |
| 431 | Kahn George Operating Co | Seminole, OK 74818 | Oil & Gas Operator | Nov 2000 |
| 432 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2025 |
| 433 | Kandletop Operating, LLC | Oklahoma City, OK 73106 | Oil & Gas Operator | Jun 2025 |
| 434 | Kansas Gas Purchasing | Salina, KS 67401 | Oil & Gas Operator | May 1995 |
| 435 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Jun 2025 |
| 436 | Keesee Paul Inc | Holdenville, OK 74848 | Oil & Gas Operator | Nov 1998 |
| 437 | Keith F. Walker Oil & Gas Co., LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Jul 2025 |
| 438 | Kelley James C Estate | Norman, OK 73072 | Oil & Gas Operator | Mar 2015 |
| 439 | Kelton Oil & Gas Co | Wheeler, TX 79096 | Oil Operator | Jun 1991 |
| 440 | Kepco. Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 441 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 442 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | May 2025 |
| 443 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 444 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 445 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 446 | Key Operating Co., Inc. | Duncan, OK 73534-1284 | Oil & Gas Operator | Jan 2025 |
| 447 | Kidd Bill R | Bristow, OK 74010-9721 | Oil Operator | Jan 2013 |
| 448 | Kiester Operating Company | Oklahoma City, OK 73106 | Oil & Gas Operator | May 2025 |
| 449 | Kingery Drilling Co., Inc. | Ardmore, OK 73402 | Oil & Gas Operator | Jun 2025 |
| 450 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 451 | Kirrie Oil Company LLC | Oklahoma City, OK 73113-0125 | Oil & Gas Operator | Jun 2025 |
| 452 | Kiska Oil Company | Tulsa, OK 74114 | Oil & Gas Operator | Jan 2019 |
| 453 | KLBW Partners, L.L.C. | Ratliff City, OK 73481 | Oil & Gas Operator | Jun 2025 |
| 454 | Kloberdanz, Paul E. | Oklahoma City, OK 73157 | Oil & Gas Operator | Aug 2021 |
| 455 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 456 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 457 | Kybenco Disposals LLC | Maysville, OK 73052 | Oil Operator | Sep 2022 |
| 458 | L.E. Jones Operating, Inc. | Duncan, OK 73534 | Oil & Gas Operator | Aug 2025 |
| 459 | Lackey Raymond R | Lindsay, OK 73052 | Oil & Gas Operator | Jun 2015 |
| 460 | Lackey Raymond R & Assoc | Sulphur, OK 73086 | Oil & Gas Operator | Jun 2025 |
| 461 | Ladd Petroleum Corp. | Denver, CO 80202 | Oil & Gas Operator | Oct 2004 |
| 462 | Ladder Energy Company | Tulsa, OK 74120-4281 | Oil & Gas Operator | Jan 2018 |
| 463 | Laguna Petroleum Corporation | Houston, TX 77046 | Oil & Gas Operator | Oct 2025 |
| 464 | Lam Financial Holdings LTD | Greenwood VIllage, CO 80111 | Oil Operator | Jul 2025 |
| 465 | Lambdin William H | Oklahoma City, OK 73120 | Oil & Gas Operator | Nov 1998 |
| 466 | Lambert Company LLC | Healdton, OK 73438-0962 | Oil & Gas Operator | Jun 2025 |
| 467 | Lambert Company The | Healdton, OK 73438-0962 | Oil & Gas Operator | Feb 2023 |
| 468 | Lamima Corporation | Ardmore, OK 73401 | Oil Operator | Nov 1994 |
| 469 | Lance Ruffel Oil & Gas LLC | Oklahoma City, OK 73102-5632 | Oil & Gas Operator | Jul 2025 |
| 470 | Landmark Exploration Co | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2013 |
| 471 | Landmark Production Company | MC Gregor, TX 76657 | Oil & Gas Operator | Oct 2010 |
| 472 | Langley Harold | Graham, OK 73437 | Oil Operator | Jun 2025 |
| 473 | Lapetco Inc | Plano, TX 75093 | Oil & Gas Operator | Aug 2024 |
| 474 | Lariat Petroleum Inc | Tulsa, OK 74119 | Oil & Gas Operator | Sep 2024 |
| 475 | Lario Oil & Gas Company | Odessa, TX 79762 | Oil & Gas Operator | Oct 2025 |
| 476 | Larkin Energy Company Inc | Sasakwa, OK 74867 | Oil & Gas Operator | May 2022 |
| 477 | Larkin Oil Co | Sasakwa, OK 74867 | Oil & Gas Operator | Aug 2015 |
| 478 | Lasmo Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2024 |
| 479 | Latigo Drilling Corporation | Duncan, OK 73533 | Oil & Gas Operator | Jun 2025 |
| 480 | Laurco Energies,Inc | | Oil & Gas Operator | May 2025 |
| 481 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 482 | Le Norman Partners LLC | Duncan, OK 73533-9523 | Oil & Gas Operator | Feb 2012 |
| 483 | Leasehold Management Corp | Oklahoma City, OK 73107 | Oil & Gas Operator | Nov 2024 |
| 484 | Lee Energy Exploration LTD | Oklahoma City, OK 73102-7114 | Oil & Gas Operator | Jul 2008 |
| 485 | Leed Energy LLC | Purcell, OK 73080-1383 | Oil & Gas Operator | Jun 2025 |
| 486 | Leeman Don J | Oklahoma City, OK 73112 | Oil & Gas Operator | Sep 1998 |
| 487 | Leeman Energy Corporation | Oklahoma City, OK 73118-1802 | Oil & Gas Operator | Mar 2015 |
| 488 | Lemley Oil Corporation | Sulphur, OK 73086-9316 | Oil & Gas Operator | Jan 2025 |
| 489 | Lewis J K | Duncan, OK 73534-1742 | Oil & Gas Operator | Apr 2015 |
| 490 | Lewis John L Well Service | Sasakwa, OK 74867 | Oil Operator | May 2013 |
| 491 | Lewis Oil Operations LLC | Ratliff City, OK 73481 | Oil & Gas Operator | Jun 2025 |
| 492 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jun 2025 |
| 493 | Lincoln Rock Corporation | Northfield, IL 60093 | Oil & Gas Operator | Jul 2003 |
| 494 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Jun 2025 |
| 495 | Little O Oil Company | Velma, OK 73091-0425 | Oil & Gas Operator | Apr 2015 |
| 496 | Little River Energy Company | Drumright, OK 74030 | Oil & Gas Operator | Jun 2025 |
| 497 | Longfellow Energy, LP | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 498 | Lucky Ace Petroleum LLC | Carrollton, TX 75010-4232 | Oil Operator | Oct 2021 |
| 499 | Lucky Oil Company | Comanche, OK 73529-0009 | Oil Operator | Dec 2024 |
| 500 | M-B Operating Co., Inc. | Rowlett, TX 75030 | Oil & Gas Operator | Oct 2025 |