| 301 | Prisum Ventures | | Oil & Gas Operator | Oct 1995 |
| 302 | Quail Oil & Gas LC | Garden City, KS 67846 | Oil & Gas Operator | Nov 2025 |
| 303 | R & B Oil & Gas | | Oil & Gas Operator | Jul 1995 |
| 304 | R & B Oil & Gas Inc | Attica, KS 67009 | Oil & Gas Operator | Sep 2025 |
| 305 | R C Taylor Operating Company LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Nov 2025 |
| 306 | R.C.Taylor Companies, Inc. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2019 |
| 307 | Rains & Williams | | Oil & Gas Operator | Nov 1995 |
| 308 | Rains & Williamson Oil Co Inc | Wichita, KS 67277 | Oil & Gas Operator | Sep 2025 |
| 309 | Raker Resources LLC | Houston, TX 77042 | Oil & Gas Operator | Dec 2025 |
| 310 | Rama Operating Company Inc | Stafford, KS 67578 | Oil & Gas Operator | Nov 2025 |
| 311 | Ramco Energy Corporation | FT. Lauderdale, FL 33312 | Oil & Gas Operator | Dec 2008 |
| 312 | Ramshorn Resources, LLC | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 313 | Range Oil Co., Inc. | Wichita, KS 67278 | Oil & Gas Operator | Jan 2020 |
| 314 | Rankin, Lennes | Sharon, KS 67138 | Gas Operator | Aug 2025 |
| 315 | Raydon Exploration, Inc. | Oklahoma City, OK 73118 | Oil & Gas Operator | Dec 2025 |
| 316 | Raymond Oil Co., Inc. | Wichita, KS 67201 | Oil & Gas Operator | Sep 2025 |
| 317 | Raymond Oil Comp | | Oil & Gas Operator | Dec 1996 |
| 318 | Reach Petroleum | | Oil & Gas Operator | Jan 1994 |
| 319 | Reach Petroleum Corporation | Wichita, KS 67218 | Oil & Gas Operator | Dec 2009 |
| 320 | Red Cedar Oil, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Jul 2025 |
| 321 | Red Hills Energy, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Sep 2025 |
| 322 | Redland Resources LLC | Oklahoma City, OK 73127 | Oil & Gas Operator | Nov 2025 |
| 323 | Reed Oil Company | Gainesville, TX 76241 | Oil & Gas Operator | Jun 2005 |
| 324 | Resource Operations Inc | Tulsa, OK 74157 | Oil & Gas Operator | May 2016 |
| 325 | Resource Venture | | Oil & Gas Operator | Oct 1991 |
| 326 | Resources & Investment Co. | Mandeville, LA 70448 | Oil Operator | Oct 2023 |
| 327 | Resources Invest | | Oil & Gas Operator | Jun 1985 |
| 328 | Resources Investment Corp | Denver, CO 80202 | Oil & Gas Operator | Sep 2018 |
| 329 | Rice Engineering Corporation | Great Bend, KS 67530 | Oil & Gas Operator | Feb 2023 |
| 330 | Rider, Don C. | Medicine Lodge, KS 67104 | Gas Operator | Mar 2000 |
| 331 | Rine Exploration | | Oil & Gas Operator | Jul 1994 |
| 332 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 333 | Roberts Resources, Inc. | Wichita, KS 67275 | Oil & Gas Operator | Sep 2025 |
| 334 | Robinson Oil Com | | Oil & Gas Operator | Feb 1995 |
| 335 | Rupe Oil Company Inc | Wichita, KS 67278 | Oil & Gas Operator | Sep 2025 |
| 336 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2025 |
| 337 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Dec 2025 |
| 338 | Sharp Engineerin | | Oil Operator | Aug 1995 |
| 339 | Shelby Resources LLC | Denver, CO 80207 | Oil & Gas Operator | Sep 2025 |
| 340 | Sierra Drilling | | Oil Operator | Sep 1988 |
| 341 | Silver Creek Oil | Merkel, TX 79536 | Oil & Gas Operator | Aug 2003 |
| 342 | Single Barrel Oil And Gas LLC | Granbury, TX 76048 | Oil & Gas Operator | Dec 2025 |
| 343 | Siroky Oil Management | Pratt, KS 67124 | Oil & Gas Operator | Sep 2025 |
| 344 | Smith Oil Operations | | Oil & Gas Operator | Sep 2025 |
| 345 | Sokan Operating, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Sep 2025 |
| 346 | Source Petroleum | Wichita, KS 67202 | Oil & Gas Operator | Oct 1993 |
| 347 | Sunwest Explorat | | Oil & Gas Operator | Nov 1985 |
| 348 | Superior Oil Com | | Oil & Gas Operator | Dec 1994 |
| 349 | Tapstone Energy LLC | Oklahoma City, OK 73101 | Oil & Gas Operator | Nov 2025 |
| 350 | Targa Pipeline Mid-Continent Westok LLC | Sulphur, LA 70665 | Gas Operator | Sep 2025 |
| 351 | Te-Pe Oil & Gas | | Oil & Gas Operator | Sep 2025 |
| 352 | Tenneco Oil Comp | | Oil & Gas Operator | Aug 1995 |
| 353 | Texas Energies I | | Oil & Gas Operator | Aug 1994 |
| 354 | Texas Energies Inc | Pratt, KS 67124 | Oil & Gas Operator | Aug 1998 |
| 355 | Texkan Resources, LLC | Odessa, TX 79765 | Oil & Gas Operator | Jun 2025 |
| 356 | Todd C H Incorpo | | Oil & Gas Operator | Feb 1994 |
| 357 | Toto Energy, LLC | Spring, TX 77380 | Oil & Gas Operator | Dec 2019 |
| 358 | Trans Pacific Oi | | Oil & Gas Operator | May 1995 |
| 359 | Trans Pacific Oil Corporation | Wichita, KS 67202 | Oil & Gas Operator | Nov 2025 |
| 360 | Trek Aec, LLC | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 361 | Triple S Construction | Blue Mound, KS 66010 | Gas Operator | Sep 2025 |
| 362 | Turnco Drilling, Inc. | Portland, OR 97208 | Oil & Gas Operator | Dec 2009 |
| 363 | Union Pacific Re | | Oil & Gas Operator | Dec 1996 |
| 364 | Union Pacific Resour | | Oil & Gas Operator | Apr 2002 |
| 365 | Union Texas Petroleum | Houston, TX 77252 | Oil & Gas Operator | Oct 1991 |
| 366 | United Energy, Inc. | Wichita, KS 67230 | Oil & Gas Operator | Dec 2002 |
| 367 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2023 |
| 368 | Upland Resources LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2025 |
| 369 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Dec 2025 |
| 370 | Val Energy, Inc. | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 371 | Vanon Energy Inc | Fort Worth, TX 76162 | Oil & Gas Operator | Jul 2022 |
| 372 | Vaughn Good Oil Co. | | Gas Operator | Sep 2025 |
| 373 | Vess Oil Corporation | Dallas, TX 75201 | Oil & Gas Operator | Dec 2025 |
| 374 | Vess Transpacifi | | Oil & Gas Operator | Jul 1995 |
| 375 | Vess-Transpacific Operating Co., Inc. | Wichita, KS 67201 | Oil & Gas Operator | May 2024 |
| 376 | Vincent Oil Corp | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 377 | VT Energy Partners, LLC | Andover, KS 67002 | Oil & Gas Operator | Dec 2019 |
| 378 | Walker Ervin G | | Oil Operator | Jul 1992 |
| 379 | Walker, Ervin Gilbert | Medicine Lodge, KS 67104 | Oil & Gas Operator | Apr 2020 |
| 380 | Wapiti Petroleum, LLC | | Oil & Gas Operator | Sep 2025 |
| 381 | Watts Oil And Gas | Hardtner, KS 67057 | Oil Operator | Apr 2006 |
| 382 | Wellwin Drilling | | Oil & Gas Operator | Dec 1994 |
| 383 | Wellwin Drilling Corporation | Wellington, KS 67152 | Oil & Gas Operator | Sep 2025 |
| 384 | Westmore Drillin | | Oil & Gas Operator | Oct 1995 |
| 385 | Westmore Drilling Company, Inc. | Lawrence, KS 66047 | Oil & Gas Operator | Dec 2019 |
| 386 | White & Ellis DR | | Oil & Gas Operator | Aug 1995 |
| 387 | White & Ellis Drilling, Inc. | Wichita, KS 67206 | Oil & Gas Operator | Sep 2025 |
| 388 | White Exploration Inc | Wichita, KS 67278 | Oil & Gas Operator | Sep 2025 |
| 389 | White Pine Petroleum Corporation | Wichita, KS 67202 | Oil & Gas Operator | Dec 2019 |
| 390 | White, Kenneth S. | Wichita, KS 67220 | Oil & Gas Operator | Sep 2022 |
| 391 | White, Robert F. | Wichita, KS 67220 | Oil & Gas Operator | Feb 2007 |
| 392 | Wildcat Oil & Gas LLC | Seneca, KS 66538 | Oil & Gas Operator | Sep 2025 |
| 393 | Wind River Exploration Inc | Sewickley, PA 15143 | Oil & Gas Operator | Sep 2025 |
| 394 | WM KS Energy Resources LLC | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2019 |
| 395 | Woolsey Operating Company, LLC | Wichita, KS 67226 | Oil & Gas Operator | Sep 2025 |
| 396 | Woolsey Petroleum Corporation | Wichita, KS 67202 | Oil & Gas Operator | Sep 2025 |
| 397 | Wortman Farms, LLC | Medicine Lodge, KS 67104 | Oil & Gas Operator | Dec 2017 |
| 398 | Xanadu Exploration Company | Broken Arrow, OK 74014 | Oil & Gas Operator | Nov 2025 |
| 399 | Younger Energy C | | Oil & Gas Operator | Dec 1996 |
| 400 | Younger Energy Company | Wichita, KS 67206 | Oil & Gas Operator | Dec 2025 |