| 1 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 2 | Sabco Operating Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Jun 2018 |
| 3 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jul 2025 |
| 4 | Samson Gas Producing Company | Tulsa, OK 74103 | Oil & Gas Operator | May 2001 |
| 5 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 6 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Apr 2025 |
| 7 | San Francisco-Okla Pet Ex Inc | | Oil & Gas Operator | Apr 2014 |
| 8 | Sandra Corporation (The) | Pampa, TX 79066-2474 | Gas Operator | Oct 1996 |
| 9 | Sanguine Gas Exploration, LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jul 2025 |
| 10 | Santa Fe Minerals, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Sep 2013 |
| 11 | Santa Fe Operating LLC | Frisco, TX 75034 | Gas Operator | Jul 2025 |
| 12 | Santa Fe-Andover Oil Co | Tulsa, OK 74172 | Oil & Gas Operator | Sep 2000 |
| 13 | Scana Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Dec 1999 |
| 14 | Scana Petroleum Resources Inc | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 15 | Schmid Properties Inc | Hico, TX 76457 | Oil & Gas Operator | Jul 2025 |
| 16 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 17 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 18 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 19 | Sedna Energy LLC | Blanchard, OK 73010-8043 | Gas Operator | Apr 2017 |
| 20 | Sellmeyer Frank | San Rafael, CA 94901-1339 | Oil Operator | Dec 2014 |
| 21 | Seneca Oil Company | Tulsa, OK 74121-1518 | Oil & Gas Operator | Jan 2015 |
| 22 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2025 |
| 23 | Shields Energy Inc | Fort Smith, AR 72901-4607 | Oil & Gas Operator | Apr 2025 |
| 24 | Shields Operating, Inc | Fort Smith, AR 72901-3834 | Oil & Gas Operator | Oct 2021 |
| 25 | Siegfried R H Inc | Tulsa, OK 74104 | Oil & Gas Operator | Mar 2008 |
| 26 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | Apr 2025 |
| 27 | Sinclair Oil & Gas Company | Salt Lake Cty, UT 84130 | Oil & Gas Operator | Jul 2025 |
| 28 | Six "E" Trading Company | Henryetta, OK 74801 | Oil & Gas Operator | Sep 2020 |
| 29 | SJM Inc | Tulsa, OK 74133-1757 | Gas Operator | Apr 2006 |
| 30 | Slawson, Donald C. | Wichita, KS 67202 | Oil & Gas Operator | Oct 2024 |
| 31 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | May 2025 |
| 32 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Jul 2025 |
| 33 | Smith Energy Company LLC | Purcell, OK 73080-4772 | Oil & Gas Operator | May 2015 |
| 34 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 35 | Sogc, Inc. | Salt Lake Cty, UT 84131 | Oil & Gas Operator | May 2025 |
| 36 | Sorrels J R Dba Cheyenne Oil Properties | Ponca City, OK 74601 | Oil & Gas Operator | Jul 2022 |
| 37 | Southern Resources Inc | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | May 2025 |
| 38 | Southern Union Exploration Co. | Austin, TX 78701 | Oil & Gas Operator | Feb 2002 |
| 39 | Spartan Resources LLC | Oklahoma City, OK 73116 | Oil & Gas Operator | May 2025 |
| 40 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | May 2025 |
| 41 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 42 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 43 | Staab Alan R | Tulsa, OK 74114-4213 | Oil & Gas Operator | Sep 2010 |
| 44 | Stalwart Energy Co | Tulsa, OK 74103-3518 | Oil & Gas Operator | Apr 2014 |
| 45 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | May 2025 |
| 46 | Stover Company | Tulsa, OK 74152-0786 | Oil & Gas Operator | Jan 2013 |
| 47 | Strike Energy LLC | Burneyville, OK 73430 | Oil Operator | May 2025 |
| 48 | Struthers Oil & Gas Corp | Tulsa, OK 74133 | Oil & Gas Operator | Jan 2013 |
| 49 | Summit Energy, Inc. | Littleton, CO 80127 | Oil & Gas Operator | Aug 2013 |
| 50 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Jul 2025 |
| 51 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 52 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |
| 53 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |
| 54 | Sydson D'Oro Expl. Co. | Houston, TX 77079 | Oil & Gas Operator | Jan 1992 |