| 1 | S M Hammack | | Gas Operator | Feb 2003 |
| 2 | S. G. Myers, Jr. | | Oil & Gas Operator | May 2005 |
| 3 | Sabine Pipe & Supply Co. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2004 |
| 4 | Sabine Pipe, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2026 |
| 5 | Sahara Gas & Exploration, Inc. | | Gas Operator | Mar 2002 |
| 6 | Sally Oil Company | | Oil Operator | Sep 2016 |
| 7 | Sam R. Brown | | Oil Operator | Mar 1987 |
| 8 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 9 | Sammy D. Thrash | | Oil & Gas Operator | May 2012 |
| 10 | Sammy D. Thrash, LLC | | Oil & Gas Operator | May 2019 |
| 11 | Sample Exploration | | Oil & Gas Operator | Jul 2002 |
| 12 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 13 | San Miguel Oil & Gas, Inc. | | Oil & Gas Operator | Jan 1993 |
| 14 | Sawyer Drilling & Service Inc. | | Oil & Gas Operator | Oct 2004 |
| 15 | Sayes Drilling Inc. | | Oil Operator | May 1987 |
| 16 | Scogin Exploration Inc | | Oil & Gas Operator | Dec 1999 |
| 17 | Scott W. Brumley | | Oil Operator | Apr 2011 |
| 18 | SDG Services LLC | Kilgore, TX 75663 | Oil Operator | Sep 2025 |
| 19 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 20 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 21 | Seagull Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 22 | Sendero Energy Inc. | Dallas, TX 75205 | Oil & Gas Operator | Feb 2026 |
| 23 | Ses Production | | Oil & Gas Operator | Oct 2023 |
| 24 | SG Interests, Inc. | Houston, TX 77010 | Oil & Gas Operator | Jun 2007 |
| 25 | Shelby Operating Company | Dallas, TX 75205 | Oil & Gas Operator | Feb 2026 |
| 26 | Shoco Production, L.P. | Kilgore, TX 75663 | Oil & Gas Operator | May 2020 |
| 27 | Shoreline Southeast LLC | | Oil & Gas Operator | Jun 2017 |
| 28 | SHS Operating Company | Shreveport, LA 71149 | Oil & Gas Operator | Jan 2025 |
| 29 | Shufflin Energy | | Oil & Gas Operator | Sep 2011 |
| 30 | Sigma Energy, LLC | | Oil Operator | Jan 2025 |
| 31 | Silver Hill Energy Operating, LLC | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 32 | Skinner Energy Management, Inc. | Shreveport, LA 71135 | Oil & Gas Operator | Jan 2011 |
| 33 | Sklar & Phillips Oil Co. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2000 |
| 34 | Sklar Exploration Company LLC | Shreveport, LA 71101 | Oil & Gas Operator | Feb 2026 |
| 35 | Smith Operating And MGMT Co. | Shreveport, LA 71161 | Oil & Gas Operator | Jun 2023 |
| 36 | SND Operating, L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Feb 2026 |
| 37 | Solid Rock Prod. | | Oil Operator | Nov 1994 |
| 38 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 39 | Source Petroleum Inc. | San Antonio, TX 78265 | Oil & Gas Operator | Feb 2026 |
| 40 | South Central Petroleum, Inc. | | Oil & Gas Operator | Dec 1988 |
| 41 | Southern Oil & Gas Company | | Oil & Gas Operator | Mar 2011 |
| 42 | Southern States Gas & Oil LTD | | Oil & Gas Operator | Jul 2004 |
| 43 | Southern States Oil Production, LLC | | Oil & Gas Operator | Oct 2013 |
| 44 | Southwest Operating Inc. | | Oil & Gas Operator | Dec 2024 |
| 45 | Southwestern Electric Power Co | Dallas, TX 75266 | Oil & Gas Operator | Dec 1989 |
| 46 | Sovereign Energy Corp. | | Oil Operator | Dec 2001 |
| 47 | Spicy Daugx Operators Louisiana LLC | | Oil & Gas Operator | Nov 2024 |
| 48 | Spyglass Oil & Gas LLC | | Oil & Gas Operator | Dec 2024 |
| 49 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 50 | Standard Production | | Oil Operator | Oct 1997 |
| 51 | Star Falcon Oil Co. | | Oil Operator | Feb 1986 |
| 52 | Stewart Oil Co. | | Oil Operator | Jun 2009 |
| 53 | Stinhall Corporation | | Oil & Gas Operator | Apr 1989 |
| 54 | Stratco Operating Co Inc | Austin, TX 78701 | Oil & Gas Operator | Feb 2026 |
| 55 | Stroud Operating LLC | | Oil & Gas Operator | Dec 2012 |
| 56 | Stroud Petroleum, Inc. | Shreveport, LA 71162 | Oil & Gas Operator | Feb 2026 |
| 57 | Stroud Production LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 58 | Stuart Oil | | Oil Operator | Jan 2025 |
| 59 | Studley Resources Corporation | Humble, TX 77347 | Oil & Gas Operator | Dec 1996 |
| 60 | STZ Petroleum Inc. | Houston, TX 77268 | Oil & Gas Operator | Dec 1997 |
| 61 | Sugar Oil Company | | Oil & Gas Operator | Feb 2011 |
| 62 | Sullivan Well Service | | Oil Operator | Mar 2010 |
| 63 | Sulphur River Exploration, Inc. | Dallas, TX 75244 | Oil & Gas Operator | Feb 2026 |
| 64 | Summit Gas LLC | | Oil & Gas Operator | Oct 2011 |
| 65 | Summit Operating LLC | Boulder, CO 80301 | Oil & Gas Operator | Nov 2025 |
| 66 | Sun Exploration And Production Co | | Oil & Gas Operator | Jan 1990 |
| 67 | Sundance Energy Corporation | | Oil & Gas Operator | Jan 2025 |
| 68 | Sunland Production Company, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2025 |
| 69 | SWN Production (Louisiana), LLC | | Oil & Gas Operator | Dec 2024 |