| 301 | Concorde Resources Corporation | Eufaula, OK 74432 | Oil & Gas Operator | Apr 2025 |
| 302 | Condor Energy | | Oil Operator | Aug 1995 |
| 303 | Condor Energy Inc | Great Bend, KS 67530 | Oil & Gas Operator | Oct 2021 |
| 304 | Condor Petroleum | | Oil & Gas Operator | Nov 1990 |
| 305 | Condry Oil Compa | | Oil Operator | May 1992 |
| 306 | Conley, Harry | Colony, KS 66015 | Oil Operator | Mar 2025 |
| 307 | Connell, Mark Allen | Claflin, KS 67525 | Oil Operator | Mar 2025 |
| 308 | Conner, Eugene | Bartlesville, OK 74005 | Oil & Gas Operator | Jul 2020 |
| 309 | Conner, Rick | Winfield, KS 67156 | Oil Operator | Aug 2019 |
| 310 | Conoco Inc. | Houston, TX 77252 | Oil & Gas Operator | Mar 2015 |
| 311 | Conoco Incorpora | | Oil & Gas Operator | Apr 1988 |
| 312 | Conrade Patsy | | Oil Operator | Jan 1986 |
| 313 | Considine, Barry | Burrton, KS 67020 | Gas Operator | Mar 2025 |
| 314 | Consolidated Gas & Energy Corp. | San Diego, CA 92130 | Oil Operator | Apr 2012 |
| 315 | Consolidated Oil | | Oil Operator | Jul 1996 |
| 316 | Consolidated Oil & Gas Inc | Wichita, KS 67202 | Oil & Gas Operator | Dec 2012 |
| 317 | Consolidated Oil Well Services, Inc | Chanute, KS 66720 | Oil Operator | Jan 2008 |
| 318 | Continental Brok | | Oil Operator | Oct 1994 |
| 319 | Continental Ener | | Oil & Gas Operator | Dec 1996 |
| 320 | Continental Energy | Garden City, KS 67846-0918 | Oil & Gas Operator | Jul 2017 |
| 321 | Continental Expl | | Oil Operator | Sep 1991 |
| 322 | Continental Oil | | Oil Operator | Jun 1985 |
| 323 | Continental Operating Co. | Houston, TX 77024 | Oil & Gas Operator | Jul 2025 |
| 324 | Continental Resources, Inc. | Oklahoma City, OK 73126 | Oil & Gas Operator | Jul 2025 |
| 325 | Continuum Midstream, LLC | Tulsa, OK 74136 | Oil Operator | Mar 2025 |
| 326 | Convest Energy Corporation | Houston, TX 77057 | Oil & Gas Operator | Sep 2014 |
| 327 | Cook Operating C | | Oil Operator | May 1987 |
| 328 | Cook, James A. | Augusta, KS 67010 | Oil Operator | Jul 1997 |
| 329 | Cooke, Donald E./Lee Wanda | Coffeyville, KS 67331 | Oil Operator | Dec 2001 |
| 330 | Cooper Oil Company | Andover, KS 67002 | Oil Operator | Oct 1997 |
| 331 | Cooper Service Co. | | Oil & Gas Operator | Nov 2024 |
| 332 | Cooper, J. M. | Winfield, KS 67119 | Oil Operator | Oct 1997 |
| 333 | Cooper, Lowell E. | Peabody, KS 66866 | Oil Operator | Nov 1987 |
| 334 | Copperhead Creek Enterprises, Inc. | Chautauqua, KS 67334 | Oil Operator | Sep 2019 |
| 335 | Copperhead Oil | Colony, KS 66015 | Oil Operator | Sep 1985 |
| 336 | Coral Coast Petroleum, L.C. | Wichita, KS 67226 | Oil & Gas Operator | Nov 2019 |
| 337 | Coral Production Corporation | Denver, CO 80201 | Oil & Gas Operator | Apr 2025 |
| 338 | Corie Oil Co., Inc. | Russell, KS 67665 | Oil Operator | Feb 2003 |
| 339 | Corie Oil Compan | | Oil Operator | Jul 1985 |
| 340 | Corlena Oil Company | Amarillo, TX 79101 | Oil & Gas Operator | Jul 2025 |
| 341 | Cornell Rich M - | | Oil & Gas Operator | May 1993 |
| 342 | Coronado Kansas, LLC | Tulsa, OK 74133 | Oil Operator | Oct 2009 |
| 343 | Coronado Oil | Lindsborg, KS 67456 | Oil Operator | Sep 1985 |
| 344 | Coronado Oil & G | | Oil Operator | Dec 1996 |
| 345 | Coronado Oil & Gas, Inc. | Great Bend, KS 67530 | Oil Operator | Jul 2004 |
| 346 | Coronado Oil, Inc. | Salina, KS 67401 | Oil Operator | May 1990 |
| 347 | Corsair Energy, LC | Wichita, KS 67202 | Oil & Gas Operator | Apr 2004 |
| 348 | Cortam, Inc. | Augusta, KS 67010 | Oil Operator | Dec 2024 |
| 349 | Corwin, B. V. | Enid, OK 73701 | Oil & Gas Operator | Apr 2017 |
| 350 | Costilla Petroleum Corporation | Midland, TX 79702 | Oil & Gas Operator | Mar 2015 |
| 351 | Cottonwood Oil C | | Oil & Gas Operator | Oct 1988 |
| 352 | Cougar Energies, Inc. | Oberlin, KS 67749 | Oil Operator | Jun 1996 |
| 353 | Cowboy Oil & Gas | Bristow, OK 74010-0057 | Oil & Gas Operator | Jul 2018 |
| 354 | Cowley Energy Associates, LLC | Plano, TX 75093 | Gas Operator | Dec 2009 |
| 355 | Cox Edwin L & Be | | Oil & Gas Operator | Nov 1989 |
| 356 | Cox, Wayne D. | Eureka, KS 67045 | Oil Operator | Sep 1991 |
| 357 | Craig Oil Compan | | Oil Operator | Jul 1996 |
| 358 | Craig Oil Company | | Oil Operator | Dec 2019 |
| 359 | Craig-Stephfield | | Oil & Gas Operator | Jan 1994 |
| 360 | Craig/Stephfield Oil & Gas, Inc. | Ponca City, OK 74602 | Oil & Gas Operator | Apr 2001 |
| 361 | Crane Edward | | Oil Operator | Feb 1995 |
| 362 | Crater, Gary D. | Kansas City, MO 64108 | Oil & Gas Operator | Feb 1988 |
| 363 | Crawford Oil & W | | Oil Operator | Dec 1985 |
| 364 | Crawford Oil Com | | Oil Operator | Dec 1987 |
| 365 | Crawford Oil LLC | Paola, KS 66071 | Oil Operator | Dec 2019 |
| 366 | Crawford Production Company Inc | Junction City, AR 71749 | Oil & Gas Operator | Mar 2025 |
| 367 | Crazy Horse Oil | | Oil Operator | Jan 2025 |
| 368 | Creco Operating, LLC | | Oil & Gas Operator | Nov 2015 |
| 369 | Crescent Drillin | | Gas Operator | Apr 1991 |
| 370 | Crescent Oil & Gas | Decatur, TX 76234 | Gas Operator | Dec 1999 |
| 371 | Crest Petr Inc | Rose Hill, KS 67133 | Oil Operator | Jun 2000 |
| 372 | Crest Petroleum | Newark, OH 43055 | Oil & Gas Operator | Nov 1993 |
| 373 | Criger Oil Compa | | Oil Operator | Sep 1992 |
| 374 | Crimson Resources, LLC | Tulsa, OK 74133 | Oil Operator | Jul 2007 |
| 375 | Cris Oil | | Oil Operator | Dec 2024 |
| 376 | Criteria Petrole | | Oil Operator | Sep 1996 |
| 377 | Crockett Oil And Gas, Inc. | Sharon, KS 67138 | Oil & Gas Operator | Jun 2006 |
| 378 | Cross And Cross | Overland Park, KS 66214 | Oil Operator | Sep 1997 |
| 379 | Cross Bar Energy, LLC | Wichita, KS 67206 | Oil Operator | Mar 2025 |
| 380 | Cross Bar Petrol | | Oil Operator | Aug 1995 |
| 381 | Cross Bar Petroleum, Inc. | Wichita, KS 67205 | Oil & Gas Operator | Jun 2016 |
| 382 | Cross Timbers Op | | Oil & Gas Operator | Nov 1996 |
| 383 | Cross Timbers Operating Co | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2025 |
| 384 | Crossfield Larry | | Oil & Gas Operator | Sep 1993 |
| 385 | Crowe Drilling C | | Oil & Gas Operator | May 1995 |
| 386 | Crown Consulting, Inc. | Liberal, KS 67905 | Oil & Gas Operator | Mar 2025 |
| 387 | Crown Energy Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Apr 2025 |
| 388 | Crown Well Service Inc | Capon Bridge, WV 26711 | Oil Operator | Mar 2025 |
| 389 | Crude Kin Oil Company, Inc. | Louisburg, KS 66053 | Oil Operator | Mar 2025 |
| 390 | Crude Producers | | Oil & Gas Operator | Sep 1988 |
| 391 | CTR 247 LLC | Peru, KS 67360 | Oil Operator | Mar 2025 |
| 392 | Cudd Operating Corp. | Oklahoma City, OK 73118 | Oil & Gas Operator | Apr 2020 |
| 393 | Culbreath Oil & Gas Company, Inc. | Tulsa, OK 74135 | Oil & Gas Operator | Apr 2025 |
| 394 | Cullen Corporati | | Oil & Gas Operator | Jan 1993 |
| 395 | Cullison, Jimmie I. | Moscow, KS 67952 | Oil Operator | Apr 2002 |
| 396 | Culver & Grounds | | Oil & Gas Operator | Nov 1995 |
| 397 | Culver & Grounds Oil Properties, Inc. | McPherson, KS 67460 | Oil Operator | Mar 2025 |
| 398 | Cunningham Crude, A General Partnership | Independence, KS 67301 | Oil Operator | Mar 2025 |
| 399 | Cunningham, Melvin | Medicine Lodge, KS 67104 | Oil Operator | Jan 2013 |
| 400 | Curry Oil | | Oil Operator | May 2005 |