| 1 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 2 | S & M Production Inc | Pawnee, OK 74058 | Oil & Gas Operator | Aug 2023 |
| 3 | S/H Petroleum Corporation | Hennessey, OK 73742-0477 | Oil & Gas Operator | Feb 2016 |
| 4 | Samson Hydrocarbons Company | Tulsa, OK 74103 | Oil & Gas Operator | Nov 2016 |
| 5 | Samson Resources Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 6 | Sand Resources LLC | Norman, OK 73072-4805 | Oil & Gas Operator | Aug 2012 |
| 7 | Sandy Petroleum Inc | Shawnee, OK 74801-5634 | Oil & Gas Operator | Jun 2025 |
| 8 | Sanook Inc | Oklahoma City, OK 73156-0548 | Oil & Gas Operator | Jan 2007 |
| 9 | Santa Fe Energy Company | Midland, TX 79701 | Oil & Gas Operator | Dec 2015 |
| 10 | Santa Fe Energy Operating Partner LP | Midland, TX 79701 | Oil & Gas Operator | Sep 2004 |
| 11 | Scout Energy Corporation | Edmond, OK 73083-1348 | Oil & Gas Operator | Jun 2025 |
| 12 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 13 | Seagull Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 14 | Seahawk Oil International Inc | Newport Beach, CA 92660 | Oil & Gas Operator | Oct 1997 |
| 15 | Sec Production Inc | Edmond, OK 73013-3709 | Oil & Gas Operator | Jul 2025 |
| 16 | Senax Inc | Tulsa, OK 74105-2206 | Oil & Gas Operator | Jun 2025 |
| 17 | Settlers Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Nov 2000 |
| 18 | Shamrock Well Operations LLC | Oklahoma City, OK 73118-4015 | Oil & Gas Operator | Jun 2025 |
| 19 | Sharber Billy Jack Operating | Konawa, OK 74849-0071 | Oil & Gas Operator | Mar 2015 |
| 20 | Shawver & Son Inc | Oklahoma City, OK 73154-0778 | Oil & Gas Operator | Oct 2024 |
| 21 | Shields Energy Inc | Fort Smith, AR 72901-4607 | Oil & Gas Operator | Jun 2025 |
| 22 | Shields Operating, Inc | Fort Smith, AR 72901-3834 | Oil & Gas Operator | Oct 2021 |
| 23 | Signature Exploration Inc. | Shawnee, OK 74804-4130 | Oil & Gas Operator | Mar 2015 |
| 24 | Silver Creek Oil & Gas, LLC | Flower Mound, TX 75022 | Oil & Gas Operator | Oct 2025 |
| 25 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | May 2025 |
| 26 | Singer Fleischaker Oil Op. Co. | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2002 |
| 27 | Sju Holdings LLC | Norman, OK 73072 | Oil & Gas Operator | Jun 2025 |
| 28 | Smith Production Co. | Wichita Falls, TX 76308 | Oil & Gas Operator | Oct 2025 |
| 29 | SNR Central Oklahoma Operating LLC | Oklahoma City, OK 73116-7906 | Oil Operator | Jun 2025 |
| 30 | SNR Operating, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 31 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 32 | Sooner Drilling Inc | Shawnee, OK 74802-0037 | Oil & Gas Operator | Jan 2005 |
| 33 | Southcreek Petroleum Co LLC | Blanchard, OK 73010-4911 | Oil & Gas Operator | Oct 2024 |
| 34 | Southern Mineral Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2001 |
| 35 | Southern Resources Inc | Oklahoma City, OK 73118-4821 | Oil & Gas Operator | Jun 2025 |
| 36 | Southwest Exploration Company | Oklahoma City, OK 73132-2230 | Oil & Gas Operator | Jun 2017 |
| 37 | SP Energy Development Company | Seattle, WA 98101-3277 | Oil & Gas Operator | Mar 2015 |
| 38 | Sparks Resources Inc | Bristow, OK 74010 | Oil & Gas Operator | Jul 2025 |
| 39 | Spess Oil Company Inc | Cleveland, OK 74020-4617 | Oil & Gas Operator | Jul 2025 |
| 40 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 41 | Stark Oil Properties | Asher, OK 74826 | Oil & Gas Operator | Jan 1997 |
| 42 | Statex Petroleum Inc | Dallas, TX 75229 | Oil & Gas Operator | Dec 2000 |
| 43 | Stauros Operating Company | Edmond, OK 73083-2707 | Oil & Gas Operator | Mar 2001 |
| 44 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Oct 2025 |
| 45 | Stetson Energy Corporation | Duncan, OK 73534-0098 | Oil & Gas Operator | Mar 2015 |
| 46 | Strat Land Exploration Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2025 |
| 47 | Streamline Oil And Gas Inc | Lindsey, OK 73052 | Oil & Gas Operator | Jul 2025 |
| 48 | Sullivant G W | Oklahoma City, OK 73172-1135 | Oil & Gas Operator | Aug 2001 |
| 49 | Sunterra Energy Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2009 |
| 50 | Swadley Et Al | Holdenville, OK 74848-0794 | Oil & Gas Operator | Nov 2014 |
| 51 | Sweetwater Exploration LLC | Norman, OK 73069-5636 | Oil & Gas Operator | Jun 2025 |
| 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 |