| 1 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 2 | S & S Operating Company, Inc. | Winnie, TX 77665 | Oil & Gas Operator | Oct 2025 |
| 3 | S. M. A. Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jan 1997 |
| 4 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 5 | Samson Exploration LLC | Tulsa, OK 74101 | Oil & Gas Operator | Aug 2025 |
| 6 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 7 | Sanchez-O'Brien Oil & Gas Corp | Houston, TX 77057 | Oil & Gas Operator | May 1998 |
| 8 | Sandel Energy, Inc. | Huntsville, TX 77342 | Oil & Gas Operator | Apr 2004 |
| 9 | Sanders, Larry E. Trustee | Longview, TX 75606 | Oil & Gas Operator | Oct 2025 |
| 10 | Se USA Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 11 | Sedona Oil & Gas Corporation | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 12 | Seely Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 13 | Seguro Well Service, Inc. | Gonzales, TX 78629 | Oil & Gas Operator | Oct 2025 |
| 14 | Sei Operating, LLC | Mandeville, LA 70471 | Oil & Gas Operator | Oct 2025 |
| 15 | Shoco Production LLC | Kilgore, TX 75663 | Oil & Gas Operator | Oct 2025 |
| 16 | Shoco Production, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | May 2020 |
| 17 | Silver Oak Energy, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Apr 2016 |
| 18 | Silverbow Resources Oper, LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 19 | Sisters Operating Company | Victoria, TX 77904 | Oil & Gas Operator | Nov 2010 |
| 20 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 21 | Smith Production Inc. | The Woodlands, TX 77381 | Oil & Gas Operator | Oct 2025 |
| 22 | Sonat Exploration Company -Tyler | Houston, TX 77251 | Oil & Gas Operator | Dec 1999 |
| 23 | Southern Bay Operating, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 24 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 25 | Spur Operating Co. | Austin, TX 78701 | Oil & Gas Operator | Oct 2025 |
| 26 | Square Mile Energy, L.L.C. | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 27 | Square One Corporation | Giddings, TX 78942 | Oil & Gas Operator | Dec 2012 |
| 28 | Sue-Ann Operating, L.C. | Victoria, TX 77903 | Oil & Gas Operator | Oct 2025 |
| 29 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Oct 2025 |
| 30 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 31 | Swift Energy Operating, LLC | Houston, TX 77079 | Oil & Gas Operator | Jun 2017 |