| 1 | S. Parish Oil Company, Inc. | | Oil & Gas Operator | Dec 1997 |
| 2 | S2 Energy Operating LLC | | Oil & Gas Operator | May 2023 |
| 3 | Sabine Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Jul 1996 |
| 4 | Sam Jones & Assoc Prod Div Inc | | Oil & Gas Operator | Feb 1999 |
| 5 | Sam Myers | | Oil & Gas Operator | Nov 1988 |
| 6 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 7 | Samson Exploration LLC | Tulsa, OK 74101 | Oil & Gas Operator | Aug 2025 |
| 8 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 9 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Oct 2025 |
| 10 | Sandridge Onshore, LLC | Houston, TX 77010 | Oil & Gas Operator | Jun 2014 |
| 11 | Sante Fe Minerals | | Oil & Gas Operator | Dec 1987 |
| 12 | SBM Operating Company Inc. | | Gas Operator | Sep 1997 |
| 13 | Se USA Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 14 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 15 | Seahawk Oil & Gas Company | Dallas, TX 75379 | Oil & Gas Operator | Aug 2007 |
| 16 | Semo, Inc. | | Oil & Gas Operator | Feb 2002 |
| 17 | Shelf Energy, LLC | | Oil & Gas Operator | Dec 2024 |
| 18 | Shoreline Exploration Of Texas | | Oil & Gas Operator | Oct 2000 |
| 19 | Shoreline Southeast LLC | | Oil & Gas Operator | Jun 2017 |
| 20 | Sierra Production Company | | Oil & Gas Operator | May 1986 |
| 21 | Signal Petroleum | | Oil & Gas Operator | Jul 1980 |
| 22 | SMC Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 23 | Smith Petroleum Company | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 24 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 25 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 26 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 27 | Sohio Petroleum Co. | Casper, WY 82602 | Oil & Gas Operator | Apr 1986 |
| 28 | Sohio Petroleum Co. Et Al | | Oil & Gas Operator | May 1979 |
| 29 | Sola Oil Company, Inc. | | Oil & Gas Operator | Aug 1991 |
| 30 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 31 | Source Petroleum Inc. | San Antonio, TX 78265 | Oil & Gas Operator | Oct 2025 |
| 32 | South Leeville, LLC | Houston, TX 77069 | Oil & Gas Operator | Oct 2022 |
| 33 | South Oak Production Company | | Oil & Gas Operator | Jun 2010 |
| 34 | South River Operating, LLC | | Oil & Gas Operator | Dec 2016 |
| 35 | Southampton Mineral Corp. | | Oil & Gas Operator | Aug 2005 |
| 36 | Southern Bay Operating, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 37 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 38 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 39 | Spooner Petroleum Company | | Oil & Gas Operator | Jul 2025 |
| 40 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 41 | St. Mary Energy Company | Houston, TX 77079 | Oil & Gas Operator | Aug 2008 |
| 42 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 43 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 44 | Stone Energy Corporation | Denver, CO 80202-2828 | Oil & Gas Operator | Oct 2014 |
| 45 | Stone Oil-Quasar-Birthright | | Oil & Gas Operator | Feb 1981 |
| 46 | Stone Petroleum Corporation | | Oil & Gas Operator | Dec 1996 |
| 47 | Stratco Operating Co Inc | Austin, TX 78701 | Oil & Gas Operator | Oct 2025 |
| 48 | Sulphur River Exploration, Inc. | Dallas, TX 75244 | Oil & Gas Operator | Oct 2025 |
| 49 | Summit Oil & Gas LLC | | Oil & Gas Operator | Aug 2025 |
| 50 | Sun Exploration-Production Co. | | Oil & Gas Operator | Jan 1990 |
| 51 | Sun Texas Company | | Oil & Gas Operator | Jun 1981 |
| 52 | Superior Oil Co. | Denver, CO 80217-5444 | Oil & Gas Operator | Feb 2001 |
| 53 | Superior-American Quasar | | Oil & Gas Operator | Jan 1981 |
| 54 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 55 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |