| 1 | S2 Energy 1, LP | | Oil & Gas Operator | Nov 2012 |
| 2 | S2 Energy Operating LLC | | Oil & Gas Operator | May 2023 |
| 3 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 4 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 5 | Sanare Energy Partners, LLC | | Oil & Gas Operator | Dec 2024 |
| 6 | Sandefer Petroleum Co. | | Oil & Gas Operator | Apr 1994 |
| 7 | Sante Fe Minerals | | Oil & Gas Operator | Dec 1987 |
| 8 | Senior G&A Operating Co Inc | | Oil & Gas Operator | Nov 1991 |
| 9 | Shell Offshore Inc. | New Orleans, LA 70161 | Oil & Gas Operator | Jan 2008 |
| 10 | Shell Oil Company | Houston, TX 77210 | Oil & Gas Operator | Apr 2015 |
| 11 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 12 | Shoreline Southeast LLC | | Oil & Gas Operator | Jun 2017 |
| 13 | Signal Petroleum | | Oil & Gas Operator | Jul 1980 |
| 14 | Singer-Fleischaker Oil Co Inc | | Oil & Gas Operator | Jul 1987 |
| 15 | Skelly Oil Co | | Oil & Gas Operator | Mar 2005 |
| 16 | SMC Oil & Gas, Inc. | Midland, TX 79710 | Oil & Gas Operator | Oct 2025 |
| 17 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 18 | Sohio Petroleum Co. | Casper, WY 82602 | Oil & Gas Operator | Apr 1986 |
| 19 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 20 | Source Petroleum Inc. | San Antonio, TX 78265 | Oil & Gas Operator | Oct 2025 |
| 21 | South La. Production Co., Inc. | | Oil & Gas Operator | Jun 1982 |
| 22 | South Oak Production Company | | Oil & Gas Operator | Jun 2010 |
| 23 | Southern Bay Operating, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 24 | Southern Natural Gas Co | Houston, TX 77001 | Oil & Gas Operator | Dec 2011 |
| 25 | Southport Exploration Inc | Tulsa, OK 74103-4015 | Oil & Gas Operator | Nov 1998 |
| 26 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 27 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 28 | SRP Production Corp. | | Oil & Gas Operator | Nov 1997 |
| 29 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 30 | Star Oil & Gas, Inc. | | Oil & Gas Operator | Sep 1995 |
| 31 | Stone Energy Corporation | Denver, CO 80202-2828 | Oil & Gas Operator | Oct 2014 |
| 32 | Stone Petroleum Corporation | | Oil & Gas Operator | Dec 1996 |
| 33 | Stratco Operating Co Inc | Austin, TX 78701 | Oil & Gas Operator | Oct 2025 |
| 34 | Sugar Bowl Industrial Gas Corp | | Oil Operator | Dec 1983 |
| 35 | Sulphur River Exploration, Inc. | Dallas, TX 75244 | Oil & Gas Operator | Oct 2025 |
| 36 | Sun Exploration-Production Co. | | Oil & Gas Operator | Jan 1990 |
| 37 | Superior Oil Co. | Denver, CO 80217-5444 | Oil & Gas Operator | Feb 2001 |
| 38 | Superior-Tenneco | | Oil & Gas Operator | Jun 1982 |