| 1 | S Enterprises | | Oil & Gas Operator | Nov 1986 |
| 2 | S. G. Myers, Jr. | | Oil & Gas Operator | May 2005 |
| 3 | S. G. Myers, Jr. Et Al | | Oil & Gas Operator | Jul 1991 |
| 4 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Feb 2026 |
| 5 | Sam Aertker | | Oil Operator | Jul 1992 |
| 6 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 7 | Samson Kelley Operating Co., LTD. | | Oil & Gas Operator | Feb 2004 |
| 8 | Sandefer & Andress, Inc. | | Oil & Gas Operator | Apr 1982 |
| 9 | Sandhill Production Inc | Shongaloo, LA 71072 | Oil & Gas Operator | Dec 2019 |
| 10 | Sapient Energy Corp | Oklahoma City, OK 73154 | Oil & Gas Operator | Jan 2002 |
| 11 | Seagull Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Jan 2025 |
| 12 | Ses Production | | Oil & Gas Operator | Oct 2023 |
| 13 | Shongaloo Midstream, LLC | | Oil Operator | Mar 2019 |
| 14 | Shuler Drilling Co., Inc. | El Dorado, AR 71730 | Oil & Gas Operator | Jan 2025 |
| 15 | Silver Oak Operating, Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 2009 |
| 16 | Silver Pines Energy Corp. | Houston, TX 77005 | Oil & Gas Operator | Nov 2025 |
| 17 | Sklar & Phillips Oil Co. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2000 |
| 18 | Sklar Exploration Company LLC | Shreveport, LA 71101 | Oil & Gas Operator | Feb 2026 |
| 19 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Feb 2026 |
| 20 | Smackover Drilling Co. Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Jan 2025 |
| 21 | Smith Operating And MGMT Co. | Shreveport, LA 71161 | Oil & Gas Operator | Jun 2023 |
| 22 | Smith Operating-Germany Oil | | Oil & Gas Operator | Dec 1995 |
| 23 | SMR Natural Gas Ventures Inc | Oklahoma City, OK 73112 | Oil & Gas Operator | Jan 1999 |
| 24 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 25 | Special Energy Corp. | Stillwater, OK 74076 | Oil & Gas Operator | Feb 2026 |
| 26 | St. Mary Land & Exploration Co | Denver, CO 80201 | Oil & Gas Operator | Jun 2010 |
| 27 | State Line Vacuum Services, LLC | | Oil Operator | Mar 2021 |
| 28 | Stephens & Johnson Operating Co. | Wichita Falls, TX 76307 | Oil & Gas Operator | Feb 2026 |
| 29 | Story Oil And Gas Inc | Magnolia, AR 71753 | Oil & Gas Operator | Jan 2025 |
| 30 | STS Petroleum LLC | Houston, TX 77289 | Oil & Gas Operator | Feb 2026 |
| 31 | Sun Exploration And Production Co | | Oil & Gas Operator | Jan 1990 |
| 32 | Sundance Energy Corporation | | Oil & Gas Operator | Jan 2025 |
| 33 | Sunland Production Company, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2025 |
| 34 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |