| 1 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Jun 2025 |
| 2 | Sagely, Floyd E Properties, LTD | Fort Smith, AR 72917-0308 | Gas Operator | Jan 2015 |
| 3 | Samson Gas Producing Company | Tulsa, OK 74103 | Oil & Gas Operator | May 2001 |
| 4 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 5 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2025 |
| 6 | San Francisco-Okla Pet Ex Inc | | Oil & Gas Operator | Apr 2014 |
| 7 | San Marco Petroleum Inc | Denver, CO 80293 | Oil & Gas Operator | Mar 2025 |
| 8 | Sandridge Exploration And Production LLC | Oklahoma City, OK 73104 | Oil & Gas Operator | Jun 2025 |
| 9 | Sanguine Gas Exploration, LLC | Tulsa, OK 74119 | Oil & Gas Operator | Jun 2025 |
| 10 | Santa Fe Minerals, Inc. | Dallas, TX 75240 | Oil & Gas Operator | Sep 2013 |
| 11 | Santa Fe-Andover Oil Co | Tulsa, OK 74172 | Oil & Gas Operator | Sep 2000 |
| 12 | Scarth Oil & Gas Co | Amarillo, TX 79101 | Oil & Gas Operator | Feb 1999 |
| 13 | Schmid Properties Inc | Hico, TX 76457 | Oil & Gas Operator | Jun 2025 |
| 14 | Seagull Mid-South Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 15 | Seagull Midcon Inc. | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 16 | Seaport Inc | Oklahoma City, OK 73131 | Oil & Gas Operator | Feb 2025 |
| 17 | Sedna Energy LLC | Blanchard, OK 73010-8043 | Gas Operator | Apr 2017 |
| 18 | Service Drilling Co. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 1998 |
| 19 | Service Drilling Co., L.L.C. | Tulsa, OK 74119 | Oil & Gas Operator | Oct 2003 |
| 20 | Shannon Petroleum Inc | Tulsa, OK 74136-4603 | Oil & Gas Operator | Oct 2016 |
| 21 | Shields Energy Inc | Fort Smith, AR 72901-4607 | Oil & Gas Operator | Feb 2025 |
| 22 | Siegfried R H Inc | Tulsa, OK 74104 | Oil & Gas Operator | Mar 2008 |
| 23 | Silverridge Corp | Van Buren, AR 72956 | Oil & Gas Operator | Mar 2015 |
| 24 | Slawson, Donald C. | Wichita, KS 67202 | Oil & Gas Operator | Oct 2024 |
| 25 | Sloan Petroleum Service Inc | Guthrie, OK 73044 | Oil & Gas Operator | Mar 2025 |
| 26 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Jun 2025 |
| 27 | Smith Shirley C | Claremore, OK 74017-0060 | Oil & Gas Operator | Mar 2015 |
| 28 | Snyder Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2015 |
| 29 | Sonata Oil & Gas Corp Inc | Stratford, OK 74812 | Oil & Gas Operator | Apr 2014 |
| 30 | Southern Resources Inc | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | Mar 2025 |
| 31 | Southern Union Exploration Co. | Austin, TX 78701 | Oil & Gas Operator | Feb 2002 |
| 32 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 33 | Sparks Petroleum Company | Oklahoma City, OK 73128 | Oil & Gas Operator | Mar 1998 |
| 34 | Spring Resources, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2007 |
| 35 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 36 | Stalwart Energy Co | Tulsa, OK 74103-3518 | Oil & Gas Operator | Apr 2014 |
| 37 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Mar 2025 |
| 38 | Stover Company | Tulsa, OK 74152-0786 | Oil & Gas Operator | Jan 2013 |
| 39 | Striker Management Co LLC | Shawnee, OK 74801 | Oil & Gas Operator | Feb 2025 |
| 40 | SWN Production LLC | Spring, TX 77389-4954 | Oil & Gas Operator | Feb 2022 |