| 301 | Gulf Production Corporation | Oklahoma City, OK 73114 | Oil & Gas Operator | Apr 2015 |
| 302 | Gulfport Energy Corporation | Oklahoma City, OK 73134-5003 | Oil & Gas Operator | Feb 2025 |
| 303 | Gulfstream Petroleum Corp. | | Oil & Gas Operator | Feb 2002 |
| 304 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 305 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 306 | H G & G Inc | Edmond, OK 73034 | Oil & Gas Operator | Jan 2006 |
| 307 | H.L.S. Energy Co., Inc. | Uvalde, TX 78801 | Oil & Gas Operator | Aug 2003 |
| 308 | H2ok LLC | Marble Falls, TX 78654 | Oil & Gas Operator | Mar 2025 |
| 309 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 310 | Hadson Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 311 | Halcon Holdings Inc | Ada, OK 74820 | Oil & Gas Operator | Nov 2018 |
| 312 | Hall Energy Company LLC | Oklahoma City, OK 73120-5020 | Oil & Gas Operator | Jul 2022 |
| 313 | Halliburton Oil Producing Co. | Duncan, OK 73534 | Oil & Gas Operator | Apr 2016 |
| 314 | Harbert Energy Corp | Irving, TX 75015-2510 | Oil & Gas Operator | Feb 1993 |
| 315 | Harding & Shelton Inc | Oklahoma City, OK 73104-2410 | Oil & Gas Operator | Feb 2025 |
| 316 | Hazelwood Prod & Exp Co LLC | Oklahoma City, OK 73116-9037 | Oil & Gas Operator | Jan 2025 |
| 317 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 318 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 319 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 320 | Heartland Exploration Inc | Edmond, OK 73013 | Oil & Gas Operator | Dec 2015 |
| 321 | Heath Oil Co., Inc. | Washington, OK 73093-4702 | Oil & Gas Operator | Feb 2025 |
| 322 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Feb 2025 |
| 323 | Hess Corporation | Houston, TX 77010 | Oil & Gas Operator | Aug 2017 |
| 324 | Hibbert R E Estate Of | Houston, TX 77002-3211 | Oil & Gas Operator | Apr 2015 |
| 325 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | May 2025 |
| 326 | Hill Oil Company Inc | Shawnee, OK 74804 | Oil & Gas Operator | Feb 2025 |
| 327 | Hill Resources Inc | | Oil & Gas Operator | Nov 2022 |
| 328 | Hinkle Engineering, Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Nov 2016 |
| 329 | Hinkle Oil And Gas Inc | Oklahoma City, OK 73112-4275 | Oil & Gas Operator | Mar 2025 |
| 330 | HK Energy Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2023 |
| 331 | Hodgden Operating Co., Inc. | Enid, OK 73702 | Oil & Gas Operator | Mar 2025 |
| 332 | Holden Energy Corporation | Ardmore, OK 73401 | Oil & Gas Operator | Mar 2015 |
| 333 | Holke Dave Consulting Inc | Meridian, ID 83646-4812 | Oil & Gas Operator | Feb 2025 |
| 334 | Home-Stake Royalty Corp., The | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2014 |
| 335 | Hondo Oil & Gas Company | Roswell, NM 88202 | Oil & Gas Operator | Aug 2006 |
| 336 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 337 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 338 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 339 | HRC Production Co | Houston, TX 77024 | Oil & Gas Operator | Jan 2025 |
| 340 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | May 2025 |
| 341 | Hughes George B | Asher, OK 74826-0165 | Oil & Gas Operator | Mar 2011 |
| 342 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 343 | Huitt Joe A | Tulsa, OK 74103 | Oil & Gas Operator | May 2001 |
| 344 | Hunt Engineering Inc | Norman, OK 73069-4093 | Oil & Gas Operator | Feb 2019 |
| 345 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 346 | Hunton Oil & Gas Corporation | Oklahoma City, OK 73154-0191 | Oil & Gas Operator | May 2019 |
| 347 | Hunton Operating LLC | Oklahoma City, OK 73154 | Oil & Gas Operator | Mar 2025 |
| 348 | I C Gas Amcana Inc | Tulsa, OK 74103-3713 | Oil & Gas Operator | Apr 1996 |
| 349 | Indian Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | May 2025 |
| 350 | Indrex Inc | Tulsa, OK 74133 | Oil & Gas Operator | Dec 2000 |
| 351 | Inter-States Oil & Gas Inc | Edmond, OK 73003-0023 | Oil & Gas Operator | Apr 2020 |
| 352 | Iron Sights Operating, Inc. | Stillwater, OK 74076 | Oil & Gas Operator | Jul 2022 |
| 353 | J & S Operating | Shiner, TX 77984 | Oil & Gas Operator | Dec 2002 |
| 354 | J & T Operating Inc | Norman, OK 73070-1736 | Oil & Gas Operator | Feb 2012 |
| 355 | J C Petroleum Inc | Chickasha, OK 73023-1433 | Oil & Gas Operator | Dec 2013 |
| 356 | J&R Operating | Holliday, TX 76366 | Oil & Gas Operator | Feb 2024 |
| 357 | January Investments LLC | Norman, OK 73069-8224 | Oil & Gas Operator | Mar 2025 |
| 358 | Jas Tube Well Holding LLC | Kilgore, TX 75663-3711 | Oil & Gas Operator | May 2020 |
| 359 | Jasmine Inc | Duncan, OK 73534-1103 | Oil & Gas Operator | Jun 2017 |
| 360 | Jenex Operating Company | The Woodlands, TX 77380-164280209 | Oil & Gas Operator | May 2019 |
| 361 | Jerry Sanner Oil Properties Inc | Enid, OK 73701 | Oil & Gas Operator | Mar 2025 |
| 362 | Jerry Scott Drilling Company Inc | Ada, OK 74821 | Oil & Gas Operator | Dec 2024 |
| 363 | Jetta Operating Company Inc | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 364 | Johnson E Lyle | Oklahoma City, OK 73142 | Oil & Gas Operator | Feb 2025 |
| 365 | Jolen Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2025 |
| 366 | Jones & Pellow Oil Co | Oklahoma City, OK 73118-1115 | Oil & Gas Operator | Feb 2015 |
| 367 | Jones, L. E. Production Co. | Duncan, OK 73534 | Oil & Gas Operator | Jul 2014 |
| 368 | Jwimco, L.L.C. | Dallas, TX 75229 | Oil & Gas Operator | Feb 2025 |
| 369 | K S Oil Company Inc | Norman, OK 73072-7480 | Oil & Gas Operator | Feb 2025 |
| 370 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 371 | Kandletop Operating, LLC | Oklahoma City, OK 73106 | Gas Operator | Mar 2025 |
| 372 | Katsco Energy, Inc. | Round Rock, TX 78664 | Oil & Gas Operator | May 2025 |
| 373 | KC Resources Inc | Snowmass VLG., CO 81615 | Oil & Gas Operator | Feb 2025 |
| 374 | Kechi Energy LLC | Chickasha, OK 73018 | Oil & Gas Operator | Mar 2025 |
| 375 | Keener Energy Company | Tulsa, OK 74103-4043 | Oil & Gas Operator | Jan 2014 |
| 376 | Keith F. Walker Oil & Gas Co., LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2025 |
| 377 | Kelmac Production Company | Braman, OK 74632-0132 | Oil Operator | Apr 2003 |
| 378 | Kennedy & Mitchell, Inc. | Houston, TX 77084 | Oil & Gas Operator | Aug 2013 |
| 379 | Kepco Operating, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2025 |
| 380 | Kepco. Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 381 | Kerr McGee Rocky MTN Corp | Denver, CO 80202-5736 | Oil & Gas Operator | Mar 2015 |
| 382 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | Mar 2025 |
| 383 | Kerr-McGee Oil & Gas Onshore LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2017 |
| 384 | Kerr-McGee Oil & Gas Onshore LP | Houston, TX 77046 | Oil & Gas Operator | May 2025 |
| 385 | Kimbark Oil & Gas Company | Denver, CO 80203 | Oil & Gas Operator | May 2007 |
| 386 | Kingfisher CSG Pullr & Const Inc | Hennessey, OK 73742-0024 | Oil & Gas Operator | Apr 2014 |
| 387 | Kingfisher Resources Inc | Clinton, OK 73601 | Oil & Gas Operator | Mar 2025 |
| 388 | Kirkpatrick Oil Company | Nichols Hill, OK 73116 | Oil & Gas Operator | May 2025 |
| 389 | Klo LLC | Tulsa, OK 74120-2428 | Oil & Gas Operator | Mar 2025 |
| 390 | Koch Oil Company | | Oil & Gas Operator | May 2017 |
| 391 | KWB Oil Property Management Inc | Tulsa, OK 74103 | Oil & Gas Operator | Jan 2025 |
| 392 | Kybenco Disposals LLC | Maysville, OK 73052 | Oil Operator | Sep 2022 |
| 393 | L & B Oil Company Inc | Houston, TX 77019-3115 | Oil & Gas Operator | Mar 2025 |
| 394 | L & L Smith Energy Corporation | Muskogee, OK 74403-8479 | Oil & Gas Operator | Jan 2023 |
| 395 | L E Jones Operating Inc | Duncan, OK 73534 | Oil & Gas Operator | Mar 2025 |
| 396 | Lackey Raymond R | Lindsay, OK 73052 | Oil & Gas Operator | Jun 2015 |
| 397 | Lackey Raymond R & Assoc | Sulphur, OK 73086 | Oil & Gas Operator | Mar 2025 |
| 398 | Ladd Petroleum Corp. | Denver, CO 80202 | Oil & Gas Operator | Oct 2004 |
| 399 | Lamamco Drilling Company | Skiatook, OK 74070 | Oil & Gas Operator | Feb 2025 |
| 400 | Lamb Alan L | Oklahoma City, OK 73120-7824 | Oil & Gas Operator | Feb 2020 |