| 27301 | Skelly Oil Co | | Oil & Gas Operator | Mar 2005 |
| 27302 | Skelton Operating Co., Inc. | | Oil & Gas Operator | Aug 1980 |
| 27303 | Skelton, D.W. | | Oil Operator | Dec 1952 |
| 27304 | Skewes Operating Company | Bluefield, VA 24605 | Oil & Gas Operator | Dec 2025 |
| 27305 | Ski Production, LLC | Muenster, TX 76252 | Oil Operator | Dec 2025 |
| 27306 | Skidgel Enterprises Inc | Rawlins, WY 82301 | Oil & Gas Operator | Sep 2018 |
| 27307 | Skidmore Energy,Inc. | Salado, TX 76571 | Oil & Gas Operator | Jun 1999 |
| 27308 | Skidmore Exploration, Inc. | Dallas, TX 75219 | Oil & Gas Operator | Jul 1997 |
| 27309 | Skidmore, James E. | Nocona, TX 76255 | Oil & Gas Operator | Nov 2008 |
| 27310 | Skinner Cattle, Inc. | Nocona, TX 76255 | Oil Operator | Dec 2025 |
| 27311 | Skinner Corporation | | Oil Operator | Apr 1985 |
| 27312 | Skinner Energy Management, Inc. | Shreveport, LA 71135 | Oil & Gas Operator | Jan 2011 |
| 27313 | Skinner Oil & Gas LLC | Gillette, WY 82717 | Oil & Gas Operator | Jan 2024 |
| 27314 | Skinner'S Resources & Expl Inc | | Oil & Gas Operator | Jun 2007 |
| 27315 | Skinner, Robert V. | Spearman, TX 79081 | Oil & Gas Operator | Aug 2008 |
| 27316 | Skinner, W. E. | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 2025 |
| 27317 | Skinnergy Co. | Spearman, TX 79081 | Oil & Gas Operator | Dec 2025 |
| 27318 | Skipworth, Joseph D | | Oil Operator | Dec 2021 |
| 27319 | SKKM Oil Company | | Oil Operator | Dec 1992 |
| 27320 | Sklar | | Oil & Gas Operator | Dec 2024 |
| 27321 | Sklar & Phillips - Harry Hurt | | Oil & Gas Operator | Jul 1986 |
| 27322 | Sklar & Phillips Oil Co. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2000 |
| 27323 | Sklar & Phillips Oil Co.-Entex | | Oil & Gas Operator | Aug 1978 |
| 27324 | Sklar &Phillips-Great Southern | | Oil & Gas Operator | Aug 1980 |
| 27325 | Sklar Exploration Company LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2025 |
| 27326 | Sklar-Tex L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2001 |
| 27327 | Skora, James B. | Lawtons, NY 14091 | Gas Operator | Dec 2024 |
| 27328 | Skrivanos Engineering, Inc. | Shreveport, LA 71164 | Oil & Gas Operator | Dec 2011 |
| 27329 | Skrzynski, Thomas J. | Eden, NY 14057 | Gas Operator | Dec 2024 |
| 27330 | SKS Oil | Olney, TX 76374 | Oil & Gas Operator | Dec 2025 |
| 27331 | Skubis, Daniel J. | Fredonia, NY 14063 | Gas Operator | Dec 2024 |
| 27332 | Skull Creek A LLC | Douglas, WY 82633 | Oil & Gas Operator | Nov 2025 |
| 27333 | Skull Creek Oil & Gas LLC | | Oil Operator | Jun 2025 |
| 27334 | Sky Development Corporation | Graham, TX 76450 | Oil & Gas Operator | Mar 2008 |
| 27335 | Sky Oil, L.L.C. | St. Paul, KS 66771 | Oil Operator | Dec 2004 |
| 27336 | Sky Resources, Inc. | Graham, TX 76450 | Oil & Gas Operator | Dec 2025 |
| 27337 | Skybridge Energy LLC | Jacksboro, TX 76458 | Oil & Gas Operator | Dec 2025 |
| 27338 | Skycap Energy, LLC | Oklahoma City, OK 73118 | Oil & Gas Operator | Oct 2025 |
| 27339 | Skye MS, LLC | | Oil & Gas Operator | Nov 2025 |
| 27340 | Skyhawk Energy, LLC | | Oil Operator | Dec 2024 |
| 27341 | Skyline Oil Company | Salt Lake City, UT 84111 | Oil & Gas Operator | Jan 1987 |
| 27342 | Skyline Operating Company, LLC | Alpine, UT 84004 | Oil & Gas Operator | Jul 2025 |
| 27343 | Skyliner Energy LLC | Ravenna, OH 44266 | Oil & Gas Operator | Dec 2024 |
| 27344 | Skytop Oil & Gas | Giddings, TX 78942 | Oil & Gas Operator | Dec 2025 |
| 27345 | Skyway Energy LLC | Leesburg, OH 34748 | Oil & Gas Operator | Dec 2020 |
| 27346 | SKZ Inc. | | Oil Operator | Mar 1988 |
| 27347 | Slack Oil & Gas | Refugio, TX 78377 | Oil & Gas Operator | Dec 2012 |
| 27348 | Slack, R. C. | Pecos, TX 79772 | Oil & Gas Operator | Jul 2000 |
| 27349 | Slagel, H. P. Prod. Co. | Snyder, TX 79550 | Oil & Gas Operator | Dec 2006 |
| 27350 | Slam Resources, Inc. | | Oil & Gas Operator | Apr 1994 |
| 27351 | Slant Operating, LLC | Lafayette, LA 70503 | Oil & Gas Operator | Dec 2025 |
| 27352 | Slapco - Emerald Exploration | | Gas Operator | Sep 1979 |
| 27353 | Slape Oil Company, Inc. | Houston, TX 77064 | Oil & Gas Operator | Jun 2011 |
| 27354 | Slate Holdings, Inc. | Mineral Wells, TX 76068 | Oil & Gas Operator | Dec 2025 |
| 27355 | Slate River Resources LLC | Denver, CO 80293 | Oil & Gas Operator | Apr 2008 |
| 27356 | Slatex Well Service, Inc. | Batson, TX 77519 | Oil Operator | Dec 2025 |
| 27357 | Slaughter J M Oil Company | Fort Worth, TX 76116 | Oil & Gas Operator | Jan 2001 |
| 27358 | Slaughter, Norman C. | | Oil & Gas Operator | Dec 2012 |
| 27359 | Slavens II Paul R | Tulsa, OK 74131 | Oil & Gas Operator | Oct 2025 |
| 27360 | Slawson Clifford Ray | Healdton, OK 73438 | Oil Operator | Jan 1995 |
| 27361 | Slawson Donald C | Wichita, KS 67202 | Oil & Gas Operator | Apr 2025 |
| 27362 | Slawson Explorat | | Oil & Gas Operator | Dec 1996 |
| 27363 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 27364 | Slayton Resources Inc | Roswell, NM 88202 | Oil & Gas Operator | Nov 2025 |
| 27365 | Sledge Bros. Oil Co. | Midland, TX 79702 | Oil & Gas Operator | Mar 2016 |
| 27366 | Sledge Olen | Duncan, OK 73533 | Oil Operator | Aug 2025 |
| 27367 | Sledge, H. G., Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2016 |
| 27368 | Sleeth And Brooks Oil Co. | | Oil Operator | Jul 1989 |
| 27369 | Slick Inc. | MC Gregor, TX 76657 | Oil Operator | Dec 2025 |
| 27370 | Slick Production Inc | Tulsa, OK 74132-1718 | Oil & Gas Operator | Apr 2020 |
| 27371 | Slick Production, LLC | Muenster, TX 76252 | Oil & Gas Operator | Dec 2025 |
| 27372 | Slik-Dril P & A Inc | | Oil & Gas Operator | Sep 1989 |
| 27373 | Slik-Dril, Inc | | Oil & Gas Operator | Nov 1998 |
| 27374 | Slim Hole Inc | Farmington, NM 87401-7725 | Oil & Gas Operator | May 2013 |
| 27375 | Slingshot Oil & Gas | Houston, TX 77019 | Oil Operator | Dec 2025 |
| 27376 | Slinkard, Roberta S | | Oil Operator | Jul 2025 |
| 27377 | Sliverville Oil Co LLC | Bradford, PA 16701-2770 | Oil & Gas Operator | Dec 2024 |
| 27378 | SLMW Energy Comp | | Oil Operator | Jan 1989 |
| 27379 | Slo Oil, LLC | El Dorado, KS 67042 | Oil Operator | Nov 2024 |
| 27380 | Sloan Oil Corporation | Humble, TX 77347 | Oil & Gas Operator | Mar 2015 |
| 27381 | Sloan Operations | | Oil Operator | Mar 2025 |
| 27382 | Sloan Petroleum Inc. | Midland, TX 79710 | Oil & Gas Operator | Dec 2025 |
| 27383 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | Oct 2025 |
| 27384 | Sloan Production Co | | Oil Operator | Jan 2013 |
| 27385 | Slohcin, Inc. | Shelby, MT 59474 | Oil Operator | Oct 2025 |
| 27386 | Slone Energy, LLC | Oil Springs, KY 41238 | Oil & Gas Operator | Dec 2023 |
| 27387 | Slone, VIctor R | | Oil Operator | Jul 2025 |
| 27388 | Slow Poke Production-George L. Dobson Dba | Cut Bank, MT 59427 | Gas Operator | Sep 2025 |
| 27389 | Slow Stroke Productions LLC | | Oil Operator | Aug 2025 |
| 27390 | SLS Operating LLC | Seminole, OK 74868-5876 | Oil & Gas Operator | Aug 2025 |
| 27391 | SLT Dakota Operating, Inc. | Yukon, OK 73099 | Oil & Gas Operator | Dec 2025 |
| 27392 | SLT Production LLC | Sheffield, PA 16347-0547 | Oil & Gas Operator | Dec 2024 |
| 27393 | Sludge Treating, LLC | Hobbs, NM 88240 | Oil Operator | Dec 2025 |
| 27394 | SM Energy | Denver, CO 80203-4361 | Gas Operator | Feb 2015 |
| 27395 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Dec 2025 |
| 27396 | SM Oil & Gas Inc | Skiatook, OK 74070 | Oil & Gas Operator | Aug 2025 |
| 27397 | SM Operating Company LLC | Houston, TX 77056 | Oil & Gas Operator | Dec 2025 |
| 27398 | SM&O LLC | | Oil & Gas Operator | Oct 2025 |
| 27399 | Smackco, LTD. | | Oil & Gas Operator | Oct 2002 |
| 27400 | Smackover Drilling Co. Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Jan 2025 |