| 1 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 2 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 3 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Oct 2025 |
| 4 | Santa Fe Minerals, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Sep 2013 |
| 5 | Santa Fe-Andover Oil Co | Tulsa, OK 74172 | Oil & Gas Operator | Sep 2000 |
| 6 | Schmid Properties Inc | Hico, TX 76457 | Oil & Gas Operator | Oct 2025 |
| 7 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 8 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 9 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 10 | Sevitski & Associates Inc | Pryor, OK 74361 | Oil & Gas Operator | Dec 2000 |
| 11 | Shadowpeak Operating LLC | Oklahoma City, OK 73159-6905 | Oil & Gas Operator | Jun 2025 |
| 12 | Shields Well Service Corp | Stroud, OK 74079-3410 | Oil & Gas Operator | Dec 2017 |
| 13 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Oct 2025 |
| 14 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 15 | Sogc, Inc. | Salt Lake Cty, UT 84131 | Oil & Gas Operator | Aug 2025 |
| 16 | Southern Resources Inc | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | Jun 2025 |
| 17 | Southwest Exploration Company | Oklahoma City, OK 73132-2230 | Oil & Gas Operator | Jun 2017 |
| 18 | SP Energy Development Company | Seattle, WA 98101-3277 | Oil & Gas Operator | Mar 2015 |
| 19 | Special Energy Corporation | Stillwater, OK 74076 | Oil & Gas Operator | Oct 2025 |
| 20 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Jul 2025 |
| 21 | Spring Operating Company | Edmond, OK 73034 | Oil & Gas Operator | Jul 2025 |
| 22 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 23 | St. Johns Operating #1 L.P. | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 24 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 25 | Staghorn Resources, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2015 |
| 26 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Jul 2025 |
| 27 | Stephenson W W Pet Corp | Edmond, OK 73003-0014 | Oil & Gas Operator | Jul 2017 |
| 28 | Stoneridge Oil Inc | Ponca City, OK 74601-1600 | Oil & Gas Operator | Jan 2001 |
| 29 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Oct 2025 |
| 30 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |