| 301 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Jul 2025 |
| 302 | Hutton Gas Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Mar 2015 |
| 303 | Hydrocarbon Technology Services | | Oil & Gas Operator | Dec 2000 |
| 304 | Icon Energy Company | Oklahoma City, OK 73156-1613 | Oil & Gas Operator | Apr 2025 |
| 305 | Igleheart Warren | Edmond, OK 73034-8964 | Oil & Gas Operator | Jun 2016 |
| 306 | Indian Nation Energy Company | Wewoka, OK 74884-3456 | Oil & Gas Operator | Apr 2020 |
| 307 | Ingram Exploration Inc | Seminole, OK 74868 | Oil & Gas Operator | May 2025 |
| 308 | Inland Oil Corporation | Sapulpa, OK 74066 | Oil & Gas Operator | Jan 2025 |
| 309 | Inland Operating Company | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2025 |
| 310 | Interstate Operating LLC | Tulsa, OK 74101-0535 | Oil & Gas Operator | Aug 2013 |
| 311 | Investment Equipment LLC | FT Morgan, CO 80701 | Oil & Gas Operator | May 2025 |
| 312 | J & J Production Company LLC | Okemah, OK 74859 | Oil & Gas Operator | May 2025 |
| 313 | J I Staley Co LLC | Okmulgee, OK 74447 | Oil & Gas Operator | Apr 2025 |
| 314 | J J B Oil & Gas Inc | Mineral Wells, TX 76068 | Oil & Gas Operator | Nov 1996 |
| 315 | J.D. Pittman Operating LLC | Edmond, OK 73025 | Oil & Gas Operator | Apr 2025 |
| 316 | Jackson Oilfield Service Inc | Purcell, OK 73080-4357 | Oil & Gas Operator | Jan 2021 |
| 317 | Jagger Oil LLC | Konawa, OK 74849 | Oil & Gas Operator | Apr 2025 |
| 318 | Jake Energy LLC | Prague, OK 74864 | Oil & Gas Operator | Jul 2021 |
| 319 | James Energy Company | Okmulgee, OK 74447-0275 | Oil & Gas Operator | May 2013 |
| 320 | James Oil Company | Compton, CA 90221-4399 | Oil & Gas Operator | Nov 2008 |
| 321 | Jay Petroleum Inc | Oklahoma City, OK 73154-0526 | Oil & Gas Operator | Mar 2019 |
| 322 | JCN Petroleum Corporation | Edmond, OK 73083-3357 | Oil & Gas Operator | Jun 2004 |
| 323 | Jec Operating LLC | Oklahoma City, OK 73114-2717 | Oil & Gas Operator | Apr 2025 |
| 324 | Jericho Exploration | Weleetka, OK 74880-0704 | Oil & Gas Operator | Apr 2025 |
| 325 | Jerry Sanner Oil Properties Inc | Enid, OK 73701 | Oil & Gas Operator | May 2025 |
| 326 | Jerry Scott Drilling Company Inc | Ada, OK 74821 | Oil & Gas Operator | Apr 2025 |
| 327 | Jesse'S Oilfield Service | Okemah, OK 74859 | Oil & Gas Operator | Sep 2014 |
| 328 | Jetson Operating Inc | Ada, OK 74820 | Oil & Gas Operator | Sep 2024 |
| 329 | Johnson Exploration Company | Oklahoma City, OK 73102-7008 | Oil & Gas Operator | Jun 2015 |
| 330 | Jordan Oil & Gas Company | Healdsburg, CA 95448-1919 | Oil & Gas Operator | Mar 1995 |
| 331 | K Oil Company | Houston, TX 77005 | Oil & Gas Operator | Jul 2025 |
| 332 | Kahan And Associates, Inc | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2025 |
| 333 | Kahan Louis | Tulsa, OK 74101 | Oil & Gas Operator | May 1994 |
| 334 | Kahn George Operating Co | Seminole, OK 74818 | Oil & Gas Operator | Nov 2000 |
| 335 | Kana Resources, Inc. | Dallas, TX 75243 | Oil & Gas Operator | Aug 2003 |
| 336 | Karbuhn Oil Company | Tomball, TX 77375 | Oil & Gas Operator | Jul 2025 |
| 337 | Kay Production Company Inc | Seminole, OK 74868 | Oil & Gas Operator | Apr 2025 |
| 338 | Kellogg Oil Company | Henryetta, OK 74437 | Oil & Gas Operator | Oct 2024 |
| 339 | Kelloil Inc | Fort Worth, TX 76116-5600 | Oil & Gas Operator | Mar 2015 |
| 340 | Kelly Cook Oil LLC | Shawnee, OK 74804-3148 | Oil & Gas Operator | Apr 2025 |
| 341 | Kemmerer Company Inc | Tulsa, OK 74136-7027 | Oil & Gas Operator | Feb 2025 |
| 342 | Ken Snyder Inc | Newalla, OK 74857-7107 | Oil & Gas Operator | Apr 2025 |
| 343 | Kendol Exploration Inc | Oklahoma City, OK 73105-2513 | Oil & Gas Operator | Mar 2025 |
| 344 | Kenworthy Operating Company | Tulsa, OK 74132 | Oil & Gas Operator | May 2009 |
| 345 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Apr 2025 |
| 346 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | Jul 2025 |
| 347 | Kerr-McGee Refining Corp | Oklahoma City, OK 73125 | Oil & Gas Operator | Jun 2007 |
| 348 | Klabzuba Royalty Company | Prague, OK 74864-0567 | Oil & Gas Operator | Dec 2019 |
| 349 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | May 2025 |
| 350 | Koby Oil Company LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2025 |
| 351 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 352 | Kopco, Inc. | Caney, KS 67333 | Oil & Gas Operator | May 2025 |
| 353 | Krumme Oil Company LLP | Bristow, OK 74010 | Oil & Gas Operator | Apr 2025 |
| 354 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 355 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | May 2025 |
| 356 | Lahoma Production Inc | Jenks, OK 74037 | Oil & Gas Operator | Apr 2025 |
| 357 | Lakeshore Operating, LLC | Wichita, KS 67203 | Oil & Gas Operator | Jul 2025 |
| 358 | Lance Ruffel Oil & Gas LLC | Oklahoma City, OK 73102-5632 | Oil & Gas Operator | May 2025 |
| 359 | Landers & Musgrove | Okemah, OK 74859 | Oil & Gas Operator | Mar 2015 |
| 360 | Landers & Musgrove Oil Co. Inc | Okemah, OK 74859-0266 | Oil & Gas Operator | Jan 2018 |
| 361 | Landers & Waldman Inc | Okemah, OK 74859-0660 | Oil & Gas Operator | May 2013 |
| 362 | Landers Oil & Gas Inc | Tulsa, OK 74132-2171 | Oil & Gas Operator | Apr 2025 |
| 363 | Lapetco Inc | Plano, TX 75093 | Oil & Gas Operator | Aug 2024 |
| 364 | Larry Sherman Oil LLC | Chandler, OK 74834 | Oil & Gas Operator | Jan 2025 |
| 365 | Latex Petroleum Corp. | Houston, TX 77090 | Oil & Gas Operator | Aug 2012 |
| 366 | Lawrence James Oil Prop Inc | Catoosa, OK 74015 | Oil & Gas Operator | Feb 2012 |
| 367 | Le Norman Energy Corporation | Duncan, OK 73534 | Oil & Gas Operator | Nov 2014 |
| 368 | Le Norman Partners LLC | Duncan, OK 73533-9523 | Oil & Gas Operator | Feb 2012 |
| 369 | Leasehold Management Corp | Oklahoma City, OK 73107 | Oil & Gas Operator | Nov 2024 |
| 370 | Lema Petroleum Inc | Seminole, OK 74868 | Oil & Gas Operator | Apr 2025 |
| 371 | Lincoln Tank Truck Service Inc | Stroud, OK 74079-0662 | Oil & Gas Operator | May 2013 |
| 372 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Aug 2024 |
| 373 | Little Chicago Oil & Gas Inc | Edmond, OK 73034-0809 | Oil & Gas Operator | Dec 2017 |
| 374 | Little River Energy Company | Drumright, OK 74030 | Oil & Gas Operator | May 2025 |
| 375 | Little Thunder, LLC | Bartlesville, OK 74003 | Oil Operator | Apr 2025 |
| 376 | Longbranch Oil Company | Oklahoma City, OK 73154-0735 | Oil & Gas Operator | Mar 2018 |
| 377 | Lu-Ray Petroleum LLC | Oklahoma City, OK 73121-1607 | Oil & Gas Operator | May 2025 |
| 378 | Lunar Investments Inc | Oklahoma City, OK 73118-4823 | Oil & Gas Operator | May 2025 |
| 379 | Lyons & Lyons Inc | Tulsa, OK 74119 | Oil & Gas Operator | Apr 2025 |
| 380 | M & T Production Company LLC | Tulsa, OK 74132-3742 | Oil Operator | Apr 2011 |
| 381 | M M Energy, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Apr 2025 |
| 382 | M M Resources, Inc. | Oklahoma City, OK 73156 | Oil & Gas Operator | Sep 2018 |
| 383 | M-S-C Corporation | Houston, TX 77027 | Oil Operator | May 1994 |
| 384 | Mac Engineering & Operating Co | | Oil & Gas Operator | May 2005 |
| 385 | Magellan Exploration Co LTD | Bethany, OK 73008-0909 | Oil & Gas Operator | Jun 2014 |
| 386 | Magnum Energy Inc | Norman, OK 73072-2403 | Oil & Gas Operator | May 2025 |
| 387 | Maguire James Q Inc | Norman, OK 73070-1748 | Oil & Gas Operator | Jun 2011 |
| 388 | Majors Eugene E | Holdenville, OK 74848-9603 | Oil & Gas Operator | Apr 2025 |
| 389 | Majors John Dba Majors Production Co | Weleetka, OK 74880 | Oil & Gas Operator | Apr 2025 |
| 390 | Malson Oil Company | Crawford, OK 73638 | Oil & Gas Operator | Dec 2016 |
| 391 | Manuel Corporation | Wichita, KS 67206 | Oil & Gas Operator | May 2025 |
| 392 | Marjo Operating Company Inc | Tulsa, OK 741010729 | Oil & Gas Operator | Apr 2025 |
| 393 | Mason Robert A Production Co | Edmond, OK 73013-9102 | Oil & Gas Operator | May 2013 |
| 394 | Mason, Tommy L | | Oil & Gas Operator | May 2013 |
| 395 | Mathews Exploration Corporation | Oklahoma City, OK 73155-5328 | Oil & Gas Operator | Mar 2015 |
| 396 | Matna Enterprises LLC | Maud, OK 74854-2812 | Oil & Gas Operator | Apr 2025 |
| 397 | Matthews Florine D | Bristow, OK 74010 | Oil & Gas Operator | Jan 2020 |
| 398 | Matthews Oil & Gas LLC | Weleetka, OK 74880-7312 | Oil & Gas Operator | Apr 2020 |
| 399 | Mayfield Engineering Service | Tulsa, OK 74104 | Oil & Gas Operator | Jul 2025 |
| 400 | McGoldrick Oil Company | Shreveport, LA 71129 | Oil & Gas Operator | Jul 2020 |