| 301 | Skelly Oil Co | | Oil & Gas Operator | Mar 2005 |
| 302 | Skull Creek Oil & Gas LLC | | Oil Operator | Apr 2025 |
| 303 | Skycap Energy, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | May 2025 |
| 304 | Slavens II Paul R | Tulsa, OK 74131 | Oil & Gas Operator | May 2025 |
| 305 | Slawson Clifford Ray | Healdton, OK 73438 | Oil Operator | Jan 1995 |
| 306 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2025 |
| 307 | Slawson, Donald C. | Wichita, KS 67202 | Oil & Gas Operator | Oct 2024 |
| 308 | Sledge Olen | Duncan, OK 73533 | Oil Operator | Mar 2025 |
| 309 | Slick Production Inc | Tulsa, OK 74132-1718 | Oil & Gas Operator | Apr 2020 |
| 310 | Slim Hole Inc | Farmington, NM 87401-7725 | Oil & Gas Operator | May 2013 |
| 311 | Slinkard, Roberta S | | Oil Operator | Mar 2025 |
| 312 | Sloan Oil Corporation | Humble, TX 77347 | Oil & Gas Operator | Mar 2015 |
| 313 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | May 2025 |
| 314 | Sloan Production Co | | Oil Operator | Jan 2013 |
| 315 | Slone, VIctor R | | Oil Operator | Apr 2024 |
| 316 | SLS Operating LLC | Seminole, OK 74868-5876 | Oil & Gas Operator | Apr 2025 |
| 317 | SLT Dakota Operating, Inc. | Yukon, OK 73099 | Oil & Gas Operator | Jul 2025 |
| 318 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Jul 2025 |
| 319 | SM Oil & Gas Inc | Skiatook, OK 74070 | Oil & Gas Operator | Apr 2025 |
| 320 | Smart Jr T J | Ryan, OK 73565 | Oil Operator | Sep 1994 |
| 321 | Smart Service & Equipment LLC | Muskogee, OK 74401-5262 | Oil Operator | Aug 2013 |
| 322 | Smiley Drilling Co | Oklahoma City, OK 73156-0773 | Oil & Gas Operator | Apr 1999 |
| 323 | Smith & Smith Petroleum Corp | | Oil & Gas Operator | Apr 2025 |
| 324 | Smith Al | Duncan, OK 73534-0037 | Oil Operator | Dec 1998 |
| 325 | Smith Alfred Dba A-S Oil | Walters, OK 73572 | Oil Operator | May 2025 |
| 326 | Smith Bart Oil & Gas Expl Inc | Council Hill, OK 74428-9603 | Oil & Gas Operator | Apr 2015 |
| 327 | Smith Bob W | Ardmore, OK 73403-5214 | Oil & Gas Operator | Sep 2014 |
| 328 | Smith Bradley D & Paul C | Pawhuska, OK 74056 | Oil Operator | Apr 2025 |
| 329 | Smith Brothers Enterprises | Ardmore, OK 73402 | Oil Operator | Jul 1998 |
| 330 | Smith C W & Associates Inc | Oklahoma City, OK 73178-0105 | Oil & Gas Operator | Aug 2013 |
| 331 | Smith Cheryl A | Copan, OK 74022 | Oil Operator | Jul 2024 |
| 332 | Smith Claude W | Henryetta, OK 74437-7553 | Oil Operator | May 2008 |
| 333 | Smith Conley P Operating Co | Eglewood, CO 80112-3640 | Oil & Gas Operator | Jun 2000 |
| 334 | Smith Connie M & Sheryle | Chelsea, OK 74016-1959 | Oil Operator | Feb 2017 |
| 335 | Smith Doug | Tulsa, OK 74107 | Oil & Gas Operator | Feb 2016 |
| 336 | Smith Edward F | Avant, OK 74001-0024 | Oil & Gas Operator | Nov 2014 |
| 337 | Smith Energy Company LLC | Purcell, OK 73080-4772 | Oil & Gas Operator | May 2015 |
| 338 | Smith Harmon K | Wewoka, OK 74884 | Oil & Gas Operator | Jan 2013 |
| 339 | Smith J S Production | Seminole, OK 74868 | Oil & Gas Operator | Apr 2025 |
| 340 | Smith Jack Boyd | Elkhart, IN 46515-1968 | Oil & Gas Operator | Oct 2011 |
| 341 | Smith Joyce | Okmulgee, OK 74447-6074 | Oil Operator | Mar 2025 |
| 342 | Smith Manus L MFG Inc | Oklahoma City, OK 73147 | Oil & Gas Operator | Nov 1998 |
| 343 | Smith Max Dean | Wewoka, OK 74884 | Oil & Gas Operator | Dec 2024 |
| 344 | Smith Mike D | Stillwater, OK 74074 | Oil & Gas Operator | Apr 2015 |
| 345 | Smith Oil & Gas Co., Inc. | Wichita Falls, TX 76310 | Oil Operator | Dec 2010 |
| 346 | Smith Patrica\Judith Miller | Collinsville, OK 74021-6307 | Oil Operator | Jun 2010 |
| 347 | Smith Petroleum Company | Spring, TX 77389 | Oil & Gas Operator | Jul 2025 |
| 348 | Smith Petroleum LLC | Barnsdall, OK 74002-0134 | Oil Operator | Apr 2025 |
| 349 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2025 |
| 350 | Smith Resources, L.L.C. | Marshall, TX 75671 | Oil & Gas Operator | Jul 2025 |
| 351 | Smith Richard L | Catoosa, OK 74015 | Oil & Gas Operator | Dec 2019 |
| 352 | Smith Shirley C | Claremore, OK 74017-0060 | Oil & Gas Operator | Mar 2015 |
| 353 | Smith Terry | Wewoka, OK 74884 | Oil & Gas Operator | Mar 2015 |
| 354 | Smith Vernon C | Tulsa, OK 74104 | Oil & Gas Operator | Jan 2025 |
| 355 | Smith VIcki L Palmer | Lawton, OK 73505-1701 | Oil & Gas Operator | Dec 2014 |
| 356 | Smith, W.T. | Panhandle, TX 79068 | Oil & Gas Operator | Nov 2005 |
| 357 | Smith, William M | | Oil & Gas Operator | Feb 2025 |
| 358 | Smith-Clement Exploration Inc | Edmond, OK 73013 | Oil Operator | Jul 1997 |
| 359 | Smither Energy Co LLC | Broken Arrow, OK 74011-7615 | Oil & Gas Operator | Nov 2020 |
| 360 | Smiths Investment Inc | Sperry, OK 74073-4198 | Oil Operator | Apr 2025 |
| 361 | Smokey Trail LLC | Thornton, CO 80241 | Oil & Gas Operator | May 2025 |
| 362 | Snake Creek Oil & Gas Inc | Okmulgee, OK 74447-2041 | Oil & Gas Operator | Mar 2025 |
| 363 | SND Operating, L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2025 |
| 364 | Sneed Drilling Company | Cleveland, OK 74020 | Oil & Gas Operator | Feb 2025 |
| 365 | Sneed William A Bill | Cleveland, OK 74020-1007 | Oil & Gas Operator | Apr 2025 |
| 366 | Snelgrooes Oil Company Inc | Maysville, OK 73057-0631 | Oil & Gas Operator | Nov 2014 |
| 367 | Snelgrooes Well Service Inc | Elmore City, OK 73433 | Oil & Gas Operator | May 2003 |
| 368 | SNR Central Oklahoma Operating LLC | Oklahoma City, OK 73116-7906 | Oil Operator | May 2025 |
| 369 | SNR Operating, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Jul 2025 |
| 370 | Snuffy'S Oilfield Service Inc | Hennessey, OK 73742-6511 | Oil & Gas Operator | Nov 2014 |
| 371 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 372 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 373 | Snyder Partners | Cody, WY 82414 | Oil & Gas Operator | May 2025 |
| 374 | Sogc, Inc. | Salt Lake Cty, UT 84131 | Oil & Gas Operator | May 2025 |
| 375 | Sonata Oil & Gas Corp Inc | Stratford, OK 74812 | Oil & Gas Operator | Apr 2014 |
| 376 | Song Production Company | Lindsay, OK 73052-0369 | Oil & Gas Operator | Jun 2015 |
| 377 | Sonny'S Tank Trucks Inc | Ratliff City, OK 73481 | Oil Operator | May 2025 |
| 378 | Sooner Acquisition Corp | Wichita, KS 67206 | Oil & Gas Operator | Sep 1993 |
| 379 | Sooner Crude Inc | Tulsa, OK 74136-9107 | Oil & Gas Operator | Sep 2008 |
| 380 | Sooner Drilling Inc | Shawnee, OK 74802-0037 | Oil & Gas Operator | Jan 2005 |
| 381 | Sooner Energy LLC | Norman, OK 73069 | Oil & Gas Operator | Sep 2005 |
| 382 | Sooner Exploration & Development Co Inc | Enid, OK 73702-3525 | Oil & Gas Operator | Oct 2023 |
| 383 | Sooner Oil & Gas LLC | Fairview, OK 73737-1806 | Oil & Gas Operator | Apr 2025 |
| 384 | Sooner Oil & Gas Management Inc | Crescent, OK 73028 | Oil & Gas Operator | May 2025 |
| 385 | Sooner Oilfield Services Inc | Piedmont, OK 73078-0810 | Oil & Gas Operator | May 2024 |
| 386 | Sooner Pipe & Supply Corp | | Oil & Gas Operator | Nov 2004 |
| 387 | Sooner Trend Exploration Inc | Kingfisher, OK 73750-4752 | Oil & Gas Operator | Dec 2015 |
| 388 | Sopac Exploration Inc | Drumright, OK 74030 | Oil & Gas Operator | Jun 1993 |
| 389 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 390 | South Burbank Petroleum Corporation | Midland, TX 79707-9027 | Oil Operator | Feb 2010 |
| 391 | South Forty, The, Inc. | Laverne, OK 73848 | Oil & Gas Operator | Mar 2015 |
| 392 | South Ranch Corporation | Midland, TX 79707 | Oil Operator | Sep 2019 |
| 393 | South Ranch Oil Company Inc | St. Louis, MO 63124 | Oil Operator | Sep 1996 |
| 394 | South Sands Exploration LLC | Henryetta, OK 74437-4208 | Oil & Gas Operator | Apr 2025 |
| 395 | Southbrook Energies Inc | Tulsa, OK 74153 | Oil Operator | Feb 2004 |
| 396 | Southcreek Petroleum Co LLC | Blanchard, OK 73010-4911 | Oil & Gas Operator | Oct 2024 |
| 397 | Southerland Jackie Dale Dba Skyden Oil | Duncan, OK 73533-5392 | Oil & Gas Operator | Apr 2025 |
| 398 | Southerland Joe Don Dba Taylor Oil Co | Duncan, OK 73533 | Oil & Gas Operator | Apr 2025 |
| 399 | Southerland Marquieta Dba Keta Oil Company | Loco, OK 73442 | Oil & Gas Operator | Apr 2025 |
| 400 | Southern Int'L Inc | Oklahoma City, OK 73107 | Oil & Gas Operator | May 2007 |