| 301 | Rim Oil Company | Hays, KS 67601 | Oil Operator | Jun 2001 |
| 302 | Rine Exploration | | Oil & Gas Operator | Jul 1994 |
| 303 | Ritchie Explorat | | Oil & Gas Operator | Dec 1996 |
| 304 | Ritchie Exploration, Inc. | Wichita, KS 67278 | Oil & Gas Operator | Sep 2025 |
| 305 | River Road Production, LLC | Hays, KS 67601 | Oil Operator | Feb 1997 |
| 306 | Rosel Energy, Inc. | Liberal, KS 67901 | Oil & Gas Operator | Jul 2004 |
| 307 | Roy Farr Heirs | | Oil Operator | Jun 2013 |
| 308 | Rupe Oil Company Inc | Wichita, KS 67278 | Oil & Gas Operator | Sep 2025 |
| 309 | Rush, Terry L. | Wakeeney, KS 67672 | Oil Operator | Sep 2025 |
| 310 | Russell Oil, Inc. | Edmond, OK 73083 | Oil Operator | Sep 2025 |
| 311 | S & M Oil | Hays, KS 67601 | Oil Operator | Aug 2003 |
| 312 | S & M Oil - Craw | | Oil Operator | Dec 1995 |
| 313 | Samuel Gary Jr. & Associates, Inc. | Denver, CO 80202 | Oil & Gas Operator | Sep 2025 |
| 314 | Sandlin Oil Corp | Dacono, CO 80514 | Oil & Gas Operator | Dec 2025 |
| 315 | Schlobohm, Starr F. | Wolfeboro, NH 03894 | Oil Operator | Jul 2004 |
| 316 | Schmitt Carmen I | | Oil Operator | Dec 1996 |
| 317 | Shaida, John H. | Wichita, KS 67226 | Oil & Gas Operator | Feb 2026 |
| 318 | Shelby Resources LLC | Denver, CO 80207 | Oil & Gas Operator | Sep 2025 |
| 319 | Shields Oil Prod | | Oil & Gas Operator | Aug 1995 |
| 320 | Shoreline Energy Partners, LLC | Chandler, AZ 85249 | Oil Operator | May 2011 |
| 321 | Sierra Drilling | | Oil Operator | Sep 1988 |
| 322 | Sierra Petroleum | | Oil & Gas Operator | Sep 1986 |
| 323 | Southern States | | Oil & Gas Operator | Jul 1988 |
| 324 | Spiral Energy Corp. | Midland, TX 79705 | Oil & Gas Operator | Dec 2019 |
| 325 | Staab Oil Co., A General Partnership | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 326 | Stelbar Oil Corporation, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Sep 2025 |
| 327 | Sterling Drillin | | Oil & Gas Operator | Mar 1992 |
| 328 | Stewart Petroleum Corporation | Greenwood VIllage, CO 80111 | Oil & Gas Operator | Dec 2023 |
| 329 | Stice Oil Company | | Oil Operator | Jul 2025 |
| 330 | Stratakan Exploration, LLC | Plainville, KS 67663 | Oil & Gas Operator | Sep 2025 |
| 331 | Stripper Oil Com | | Oil Operator | Nov 1996 |
| 332 | Stripper Oil Company Inc | | Oil Operator | Sep 2025 |
| 333 | Stroke Of Luck Energy & Exploration LLC | Cassoday, KS 66842 | Oil Operator | Sep 2021 |
| 334 | Sunardo Energy, Inc. | Castle Rock, CO 80104 | Oil Operator | Jan 1997 |
| 335 | T & P Oil & Gas, L.L.C. | Overland Park, KS 66212 | Oil Operator | Dec 2009 |
| 336 | Talon Group LLC | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 337 | Taylor Florence | | Oil Operator | Mar 1995 |
| 338 | Tdi, Inc. | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 339 | Te-Pe Oil & Gas | | Oil & Gas Operator | Sep 2025 |
| 340 | Tema Oil And Gas, LLC | Houston, TX 77040 | Oil & Gas Operator | Apr 2000 |
| 341 | Tengasco, Inc. | Houston, TX 77063 | Oil & Gas Operator | Sep 2025 |
| 342 | Tenneco Oil Comp | | Oil & Gas Operator | Aug 1995 |
| 343 | Terra Max Energy | | Oil Operator | Mar 1986 |
| 344 | Terra Resc Incor | | Oil Operator | Mar 1986 |
| 345 | Terrol Energy In | | Oil Operator | Feb 1993 |
| 346 | Texkan Resources, LLC | Odessa, TX 79765 | Oil & Gas Operator | Jun 2025 |
| 347 | The Bill Bowman Oil Company | | Oil Operator | Sep 2025 |
| 348 | Thomas M. Brown LLC | Plainville, KS 67663 | Oil Operator | Sep 2025 |
| 349 | Thomason Petroleum, Inc | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 350 | Thunder Oil & Gas, LLC | Ardmore, OK 73402 | Oil & Gas Operator | Dec 2025 |
| 351 | Thunderbird Dril | | Oil & Gas Operator | Nov 1995 |
| 352 | Thunderbird Drilling, Inc. | Wichita, KS 67207 | Oil Operator | Oct 2008 |
| 353 | TK Electric & Oilfield Service, LLC | Plainville, KS 67663 | Oil Operator | Sep 2025 |
| 354 | Tomlinson Oil Co Inc | Great Bend, KS 67530 | Oil & Gas Operator | May 2025 |
| 355 | Tomlinson Operating, LLC | Ketchum, ID 83340 | Oil & Gas Operator | Oct 2014 |
| 356 | Tomlinson, Sid | Hays, KS 67601 | Oil & Gas Operator | Sep 2002 |
| 357 | Trans Pacific Oil Corporation | Wichita, KS 67202 | Oil & Gas Operator | Dec 2025 |
| 358 | Trek Aec, LLC | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 359 | Trek Resources, Inc. | Dallas, TX 75207 | Oil & Gas Operator | Feb 2026 |
| 360 | Tri United, Inc | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 361 | Trich Production, Inc. | Longview, TX 75606 | Oil & Gas Operator | Jan 2025 |
| 362 | Triple 'H' Oil O | | Oil Operator | Apr 1992 |
| 363 | Trumart Oil Comp | | Oil Operator | May 1990 |
| 364 | Trumart Oil Company | Ellis, KS 67637 | Oil Operator | Dec 2000 |
| 365 | Union Pacific Re | | Oil & Gas Operator | Dec 1996 |
| 366 | Union Pacific Resour | | Oil & Gas Operator | Apr 2002 |
| 367 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2023 |
| 368 | Unrein Oil Co | | Oil Operator | Sep 2025 |
| 369 | V & F Oil Company, A General Partnership | Hays, KS 67601 | Oil Operator | Aug 2025 |
| 370 | Venture Resources | Denver, CO 80202 | Oil Operator | Dec 1993 |
| 371 | Venture Resources, Inc. | Denver, CO 80250 | Oil Operator | Sep 2025 |
| 372 | Vess Oil Corporation | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 373 | Viking Resources | | Oil & Gas Operator | Sep 1995 |
| 374 | Viking Resources, Inc. | Stafford, TX 77477 | Oil & Gas Operator | Feb 2026 |
| 375 | Wachtman-Schroeder, A General Partnership | Pawhuska, OK 74056 | Oil Operator | Aug 2025 |
| 376 | Waddell, Eric F. | Natoma, KS 67651 | Oil Operator | Aug 1995 |
| 377 | Wallace Energy I | | Oil Operator | Mar 1990 |
| 378 | Waller Oil, LLC | Stockton, KS 67669 | Oil Operator | Jun 2025 |
| 379 | Weilert Enterpri | | Oil Operator | Sep 1988 |
| 380 | White Eagle Resources Corp. | Taos, NM 87571 | Oil & Gas Operator | Jun 2016 |
| 381 | White Hawk Oil Company, A General Partnership | Tulsa, OK 74101 | Oil Operator | Sep 2025 |
| 382 | Wichita Industri | | Oil Operator | Nov 1987 |
| 383 | Wineland Oil - LLC | Hays, KS 67601 | Oil Operator | Sep 2025 |
| 384 | WM KS Energy Resources LLC | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2019 |
| 385 | Woolsey Operating Company, LLC | Wichita, KS 67226 | Oil & Gas Operator | Sep 2025 |
| 386 | Woolsey Petroleum Corporation | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 387 | Zinszer Oil Co., Inc. | Hays, KS 67601 | Oil Operator | Dec 2019 |