| 1 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 2 | Sabine Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 3 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 4 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 5 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 6 | Samson Lone Star LP | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2007 |
| 7 | Samson Lone Star, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2025 |
| 8 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 9 | Sand Springs Oil & Gas Co. | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2025 |
| 10 | Sandia Operating Corp. | San Antonio, TX 78270 | Oil & Gas Operator | May 2010 |
| 11 | Sandlot Oil & Gas LLC | Gruver, TX 79040 | Oil & Gas Operator | Oct 2025 |
| 12 | Sanguine, LTD | Tulsa, OK 74170 | Gas Operator | Oct 2003 |
| 13 | Sapient Energy Corp | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2002 |
| 14 | Sbog, LLC | Granbury, TX 76048 | Oil & Gas Operator | Feb 2021 |
| 15 | SCS Newton Oil LLC | Perryton, TX 79070 | Oil & Gas Operator | Oct 2025 |
| 16 | Scythian, LTD. | Midland, TX 79701 | Oil & Gas Operator | Dec 2020 |
| 17 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 18 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 19 | SFM Holdings, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Jul 1995 |
| 20 | Shannon Energy | Liberal, KS 67901 | Oil & Gas Operator | Feb 1999 |
| 21 | Shell Western E&P Inc. | Houston, TX 77001 | Oil & Gas Operator | May 2011 |
| 22 | Shidler, Mark L., Inc. | Houston, TX 77055 | Oil & Gas Operator | Oct 2025 |
| 23 | Sidwell Oil & Gas, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Sep 2014 |
| 24 | Sidwell Operating Company, L.P. | Amarillo, TX 79105 | Oil & Gas Operator | Oct 2025 |
| 25 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 26 | Snyder Partners | Cody, WY 82414 | Oil & Gas Operator | Jul 2025 |
| 27 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 28 | Sonat Exploration Company-MCR | Houston, TX 77251 | Oil & Gas Operator | Dec 1999 |
| 29 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 30 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 31 | St. Johns Operating #1 L.P. | Houston, TX 77060 | Oil & Gas Operator | Aug 2023 |
| 32 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 33 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 34 | Statoil Oil & Gas LP | Austin, TX 78730 | Oil & Gas Operator | Oct 2018 |
| 35 | Stelbar Oil Corp | Wichita, KS 67206 | Oil & Gas Operator | Aug 1995 |
| 36 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 37 | Stephens, Autry C. | Midland, TX 79701 | Oil & Gas Operator | Mar 2023 |
| 38 | Sting Exploration Company | Tulsa, OK 74120 | Oil Operator | Sep 2004 |
| 39 | Strat Land Exploration Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 40 | Sundance Oil & Gas, Inc. | Pampa, TX 79065 | Oil & Gas Operator | Mar 2012 |
| 41 | Sundown Energy LP | Dallas, TX 75248 | Oil & Gas Operator | Oct 2025 |
| 42 | Sundown Energy, Inc. | Dallas, TX 75240 | Oil & Gas Operator | May 2025 |
| 43 | Suoco Oil Corporation | Pampa, TX 79066 | Oil & Gas Operator | Oct 2025 |