| 1 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 2 | Sabalo Exploration Operating,LLC | Corpus Chrsti, TX 78404 | Oil & Gas Operator | Jan 2021 |
| 3 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Jun 2025 |
| 4 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 5 | San Dia Producing Company | Deanville, TX 77852 | Oil & Gas Operator | Jun 2025 |
| 6 | Sanchez-O'Brien Oil & Gas Corp | Houston, TX 77057 | Oil & Gas Operator | May 1998 |
| 7 | Sandel Energy, Inc. | Huntsville, TX 77342 | Oil & Gas Operator | Apr 2004 |
| 8 | Sandel Operating Company | Huntsville, TX 77340 | Oil & Gas Operator | Jun 2025 |
| 9 | Seguro Well Service, Inc. | Gonzales, TX 78629 | Oil & Gas Operator | Jun 2025 |
| 10 | Seneca Resources Co LLC | Cranberry Township, PA 16066 | Oil & Gas Operator | Mar 2025 |
| 11 | Seneca Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 12 | Senora Resources, Inc. | Dime Box, TX 77853 | Oil & Gas Operator | Jun 2025 |
| 13 | Sequoia Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Nov 2009 |
| 14 | Shell Western E&P | Houston, TX 77001 | Oil & Gas Operator | Jun 2025 |
| 15 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Jun 2025 |
| 16 | Shield Petroleum | College Sta, TX 77845 | Oil & Gas Operator | Jun 2025 |
| 17 | Shoreham Oil & Gas Company, Inc. | Katy, TX 77492 | Oil & Gas Operator | Jun 2025 |
| 18 | Showdown Operating, Inc. | Dallas, TX 75230 | Oil & Gas Operator | May 1996 |
| 19 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Jun 2025 |
| 20 | Silver Creek Resources, LLC | Irving, TX 75038 | Oil & Gas Operator | Apr 2017 |
| 21 | Sklar & Phillips Oil Co. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2000 |
| 22 | Smith Petroleum Company | Spring, TX 77389 | Oil & Gas Operator | Jun 2025 |
| 23 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 24 | South Texas Operating Company | San Antonio, TX 78217 | Oil & Gas Operator | Jun 2025 |
| 25 | Southern Bay Operating, L.L.C. | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 26 | Southwest Resources, Inc. | Brenham, TX 77834 | Oil & Gas Operator | Jun 2025 |
| 27 | Square One Corporation | Giddings, TX 78942 | Oil & Gas Operator | Dec 2012 |
| 28 | SSC, Inc. | Lubbock, TX 79408 | Oil & Gas Operator | Jun 2025 |
| 29 | Stanton Mineral Development Inc | Austin, TX 78759 | Oil & Gas Operator | Jun 2025 |
| 30 | Steller Energy & Investment Corp | Plano, TX 75093 | Oil & Gas Operator | Feb 2021 |
| 31 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Jun 2025 |
| 32 | Stephens, Autry C. | Midland, TX 79701 | Oil & Gas Operator | Mar 2023 |
| 33 | Stillwater Petroleum Company | College Sta, TX 77845 | Oil & Gas Operator | Nov 1997 |
| 34 | Sto Operating Company | San Antonio, TX 78258 | Oil & Gas Operator | Jun 2025 |
| 35 | Stratlynn, Inc. | Conroe, TX 77305 | Oil & Gas Operator | Mar 2008 |
| 36 | Stroud Energy, LTD. | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2006 |
| 37 | Stroud Oil Properties, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2013 |
| 38 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Jun 2025 |
| 39 | SW Operating, Inc. | Kilgore, TX 75662 | Oil & Gas Operator | Sep 2000 |