| 27001 | Simata Energy | Midland, TX 79708 | Oil & Gas Operator | May 2025 |
| 27002 | Simata Energy, LLC | Midland, TX 79708 | Oil & Gas Operator | May 2025 |
| 27003 | Simco Oil Company | | Oil Operator | Jul 1990 |
| 27004 | Simco Oil, LLC | Lytle, TX 78052 | Oil Operator | May 2025 |
| 27005 | Simco Operating | Shawnee, OK 74804-2501 | Oil Operator | Jan 2013 |
| 27006 | Simco Petroleum | Cheyenne, WY 82003 | Oil & Gas Operator | Oct 2009 |
| 27007 | Simcoe LLC | Durango, CO 81301 | Oil & Gas Operator | Mar 2025 |
| 27008 | Simcoe Oil Company | Scottsdale, AZ 85258-2553 | Oil & Gas Operator | May 2020 |
| 27009 | Simme, Steven | Elma, NY 14052 | Gas Operator | Dec 2023 |
| 27010 | Simminger, Robert John Jr | | Oil Operator | Jan 2025 |
| 27011 | Simmons Donald M | Muskogee, OK 74401 | Oil & Gas Operator | May 2013 |
| 27012 | Simmons Engr & Consulting Co | Farmington, NM 87499 | Gas Operator | Feb 2002 |
| 27013 | Simmons Evelyn B-Per Represent | Edmond, OK 73083-3610 | Oil & Gas Operator | Aug 1996 |
| 27014 | Simmons Mack McCoy | Cement, OK 73017 | Oil Operator | Feb 2025 |
| 27015 | Simmons Oil Corporation | | Oil Operator | Jan 1989 |
| 27016 | Simmons Robert Z | | Oil Operator | Dec 1990 |
| 27017 | Simmons, Inc.* D. J. | | Oil & Gas Operator | May 2020 |
| 27018 | Simmons, L.B. Energy, Inc. | Midland, TX 79705 | Oil & Gas Operator | Nov 2000 |
| 27019 | Simmons, Stanley J. | Olney, TX 76374 | Oil & Gas Operator | Aug 1994 |
| 27020 | Simon Joseph W | Carney, OK 74832-0443 | Oil & Gas Operator | Dec 2016 |
| 27021 | Simon Of Bolivar Enterprises Inc | Cuba, NY 14727 | Oil & Gas Operator | Dec 2023 |
| 27022 | Simon Oil Company | Ardmore, OK 73401 | Oil Operator | Jan 2025 |
| 27023 | Simon Oil LLC | Kaycee, WY 82639 | Oil Operator | Feb 2025 |
| 27024 | Simon Royce & Joyce | Tecumseh, OK 74873-7341 | Oil Operator | Jun 2018 |
| 27025 | Simon, W. D. Oil Co. | Kermit, TX 79745 | Oil & Gas Operator | May 2025 |
| 27026 | Simple Operating LLC | Cross Plains, TX 76443 | Oil Operator | May 2025 |
| 27027 | Simpson B T Jr | Orlando, FL 32806 | Oil & Gas Operator | Dec 1986 |
| 27028 | Simpson Bros. Oil Co. | Odessa, TX 79760 | Oil & Gas Operator | Jan 2001 |
| 27029 | Simpson Bros. Oil Co.-Odessa | Odessa, TX 79760 | Oil & Gas Operator | Jan 2001 |
| 27030 | Simpson Gary H | Albion, PA 16401-8008 | Gas Operator | Dec 2014 |
| 27031 | Simpson Oil & Land Co. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2025 |
| 27032 | Simpson Oil Company | Odessa, TX 79760 | Oil & Gas Operator | Oct 2004 |
| 27033 | Simpson Operating Services, LP | Ballinger, TX 76821 | Oil & Gas Operator | May 2025 |
| 27034 | Simpson Well Service, Inc. | | Oil Operator | Dec 1996 |
| 27035 | Simpson, A. E. | Electra, TX 76360 | Oil & Gas Operator | Dec 2006 |
| 27036 | Simray GP, LLC | Richardson, TX 75080 | Oil & Gas Operator | Dec 2015 |
| 27037 | Simray Oil & Gas, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Sep 2003 |
| 27038 | Simray Operating Corp. | Richardson, TX 75080 | Oil & Gas Operator | Mar 2009 |
| 27039 | Simray Production Company LP | Richland, TX 75080 | Oil & Gas Operator | Dec 2010 |
| 27040 | Sims, John S. | Lawn, TX 79530 | Oil & Gas Operator | Aug 2003 |
| 27041 | Sinclair Development, LLC | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 27042 | Sinclair Energy Corporation | Fort Worth, TX 76177 | Oil & Gas Operator | May 2025 |
| 27043 | Sinclair Exploration Company | Abilene, TX 79604 | Oil & Gas Operator | Nov 1998 |
| 27044 | Sinclair Oil & Gas Company | Salt Lake Cty, UT 84130 | Oil & Gas Operator | May 2025 |
| 27045 | Sinclair Oil Corporation | Salt Lake Cty, UT 84130 | Oil & Gas Operator | Aug 2006 |
| 27046 | Singer Fleischaker Oil Op. Co. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2002 |
| 27047 | Singer Joseph B Expl Co | Oklahoma City, OK 73118-7486 | Oil & Gas Operator | Mar 1993 |
| 27048 | Singer Oil Co LLC | Hennessey, OK 73742 | Oil & Gas Operator | Mar 2025 |
| 27049 | Singer Oil Company | Oklahoma City, OK 73148 | Oil & Gas Operator | Feb 2025 |
| 27050 | Singer-Fleischaker Oil Co Inc | | Oil & Gas Operator | Jul 1987 |
| 27051 | Singer-Fleischaker,Dillon | | Oil & Gas Operator | Aug 1979 |
| 27052 | Single Barrel Oil And Gas LLC | Granbury, TX 76048 | Oil & Gas Operator | May 2025 |
| 27053 | Singleton Investments, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Oct 2012 |
| 27054 | Singletree Resources Inc | | Oil & Gas Operator | Aug 2014 |
| 27055 | Sink Hole, Inc. | Levelland, TX 79336 | Oil & Gas Operator | Dec 2000 |
| 27056 | Sinkhole Solutions, LLC | Bowling Green, KY 42103 | Oil Operator | Dec 2021 |
| 27057 | Sinow, G. S. | Pampa, TX 79066 | Oil & Gas Operator | Oct 1995 |
| 27058 | Siosi Oil & Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Nov 2013 |
| 27059 | Sioux Gas Company | | Oil & Gas Operator | Dec 2021 |
| 27060 | Sip'S Oil & Gas Inc | Yukon, OK 73099 | Oil & Gas Operator | May 2025 |
| 27061 | Sipple Oil Co | Beattyville, KY 41311 | Oil Operator | Dec 2012 |
| 27062 | Sir Drake Oil And Gas Company | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Sep 2022 |
| 27063 | Sirena Holdings LLC Series 1 | Moran, TX 76464 | Oil & Gas Operator | May 2025 |
| 27064 | Sirius Energy Corp. | Abilene, TX 79606 | Oil Operator | Dec 2009 |
| 27065 | Siroco Operating Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2010 |
| 27066 | Siroky Oil Management | Pratt, KS 67124 | Oil & Gas Operator | Jan 2025 |
| 27067 | Sissom Oil | Holliday, TX 76366 | Oil & Gas Operator | Mar 2008 |
| 27068 | Sissom Oil Field Services, LLC | Graham, TX 76450 | Oil Operator | May 2025 |
| 27069 | Sisters Of St. Joseph | Clarence, NY 14031 | Gas Operator | Dec 2023 |
| 27070 | Sisters Operating Company | Victoria, TX 77904 | Oil & Gas Operator | Nov 2010 |
| 27071 | Sitco Inc | Yukon, OK 73099 | Oil & Gas Operator | Jul 1995 |
| 27072 | Sitton, Ronnie Incorporated | Graford, TX 76449 | Oil & Gas Operator | Feb 2020 |
| 27073 | Situs Oil & Gas, LLC | Corpus Chrsti, TX 78414 | Oil Operator | May 2025 |
| 27074 | Sitwell, Inc. | | Oil Operator | May 2022 |
| 27075 | Sivad Energy No 4 | Akron, NY 14001 | Gas Operator | Dec 2023 |
| 27076 | Six "E" Trading Company | Henryetta, OK 74801 | Oil & Gas Operator | Sep 2020 |
| 27077 | Six Bar Oil LLC | Pine Haven, WY 82721 | Oil & Gas Operator | Mar 2025 |
| 27078 | Six C Oil | Bowie, TX 76230 | Oil & Gas Operator | Sep 2011 |
| 27079 | Six Oil Producers | Abilene, TX 79601 | Oil & Gas Operator | Sep 2002 |
| 27080 | Six-D Exploration, LLC | Hutchinson, KS 67502 | Oil Operator | Aug 2024 |
| 27081 | Six-S Properties, Inc. | Austin, TX 78767 | Oil & Gas Operator | May 2025 |
| 27082 | Sixess Energy, LLC | Midland, TX 79702 | Oil & Gas Operator | May 2025 |
| 27083 | Sizemore, James | Hardin, TX 77561 | Oil & Gas Operator | Jun 2003 |
| 27084 | SJ Energy, LLC | Englewood, CO 80112 | Oil & Gas Operator | Feb 2019 |
| 27085 | SJ Ok Oil Company | Dallas, TX 75206-9925 | Oil & Gas Operator | Feb 2025 |
| 27086 | SJM Inc | Tulsa, OK 74133-1757 | Gas Operator | Apr 2006 |
| 27087 | SJM Oil LLC | | Oil & Gas Operator | Dec 2009 |
| 27088 | Sju Holdings LLC | Norman, OK 73072 | Oil & Gas Operator | Feb 2025 |
| 27089 | SK Nemaha LLC | Houston, TX 77079-1222 | Oil & Gas Operator | Feb 2021 |
| 27090 | SK Opr Inc | Cabot, PA 16023-1250 | Gas Operator | Dec 2024 |
| 27091 | SK Plymouth LLC | Houston, TX 77079-1222 | Oil & Gas Operator | Jan 2025 |
| 27092 | Skaar, K. M. Oil & Gas Co. | Midland, TX 79710 | Oil & Gas Operator | May 2025 |
| 27093 | Skaer Properties LTD Partnership | | Oil & Gas Operator | Jun 2013 |
| 27094 | Skeet Oil Production LLC | Grady, OK 73569 | Oil Operator | Mar 2025 |
| 27095 | Skeeter Oil L.L.C. | Big Spring, TX 79720 | Oil Operator | May 2025 |
| 27096 | Skelly Oil Co | | Oil & Gas Operator | Mar 2005 |
| 27097 | Skelton Operating Co., Inc. | | Oil & Gas Operator | Aug 1980 |
| 27098 | Skelton, D.W. | | Oil Operator | Dec 1952 |
| 27099 | Skewes Operating Company | Bluefield, VA 24605 | Oil & Gas Operator | May 2025 |
| 27100 | Ski Production, LLC | Muenster, TX 76252 | Oil Operator | May 2025 |