| 1 | Sabine Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Jul 1996 |
| 2 | Sabine Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Apr 2025 |
| 3 | Sabine Production Company | | Oil & Gas Operator | Oct 1990 |
| 4 | Saga Petroleum LLC Of Colorado | Norman, OK 73072 | Oil & Gas Operator | Apr 2025 |
| 5 | Sage Butte PRB Operating, LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2025 |
| 6 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 7 | Samson Oil & Gas USA Inc | Denver, CO 80202 | Oil & Gas Operator | Feb 2025 |
| 8 | Samson Resources Company LLC | Denver, CO 80202 | Oil & Gas Operator | Feb 2021 |
| 9 | San Marco Petroleum Inc | Denver, CO 80293 | Oil & Gas Operator | Feb 2025 |
| 10 | Sands Oil Company Inc | Billings, MT 59103 | Oil & Gas Operator | Jan 2025 |
| 11 | Santa Rosa Petroleum LLC | Recluse, WY 82725 | Oil & Gas Operator | Jan 2025 |
| 12 | Scana Petroleum Resources Inc | Houston, TX 77002 | Oil & Gas Operator | Jun 2013 |
| 13 | Schmid Properties Inc | Hico, TX 76457 | Oil & Gas Operator | Apr 2025 |
| 14 | Seagull Energy E & P Inc | Houston, TX 77002 | Oil & Gas Operator | Jan 2015 |
| 15 | Seer Operating LLC | Sheridan, WY 82801 | Oil & Gas Operator | Oct 2016 |
| 16 | Seguro Oil & Gas Inc | | Oil Operator | Jul 1992 |
| 17 | Seven Sisters Oil & Gas LLC | Casper, WY 82602 | Oil & Gas Operator | Jan 2022 |
| 18 | Shar Alan Oil Company | | Oil & Gas Operator | Oct 2005 |
| 19 | Sharkey Well Service Inc | | Oil Operator | Dec 2023 |
| 20 | Shenandoah Energy Inc | Denver, CO 80265-1050 | Oil & Gas Operator | Dec 2014 |
| 21 | Sheridan Production Company, LLC | Houston, TX 77056 | Oil & Gas Operator | Jan 2025 |
| 22 | Siegfried R H Inc | Tulsa, OK 74104 | Oil & Gas Operator | Mar 2008 |
| 23 | Simasko Production Co | Denver, CO 80204 | Oil & Gas Operator | Nov 1997 |
| 24 | Six Bar Oil LLC | Pine Haven, WY 82721 | Oil & Gas Operator | Feb 2025 |
| 25 | Skinner Oil & Gas LLC | Gillette, WY 82717 | Oil & Gas Operator | Jan 2024 |
| 26 | Skull Creek A LLC | Douglas, WY 82633 | Oil & Gas Operator | Nov 2024 |
| 27 | Skyline Oil Company | Salt Lake City, UT 84111 | Oil & Gas Operator | Jan 1987 |
| 28 | Slaughter J M Oil Company | Fort Worth, TX 76116 | Oil & Gas Operator | Jan 2001 |
| 29 | Slawson Exploration Company Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2025 |
| 30 | SM Energy Company | Midland, TX 79707 | Oil & Gas Operator | Apr 2025 |
| 31 | Smith Conley P Operating Co | Eglewood, CO 80112-3640 | Oil & Gas Operator | Jun 2000 |
| 32 | Smokey Oil Company Inc | Casper, WY 82601 | Oil & Gas Operator | Dec 1996 |
| 33 | Snowy Owl LLC | Gillette, WY 82717 | Oil & Gas Operator | Feb 2025 |
| 34 | Snyder Oil Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 35 | Sonat Exploration Co. | Houston, TX 77251 | Oil & Gas Operator | Dec 2021 |
| 36 | South Coast Oil Corporation | Boulder, CO 80302 | Oil & Gas Operator | Oct 2015 |
| 37 | South Pass Petroleum Inc | Casper, WY 82601 | Oil & Gas Operator | Feb 2025 |
| 38 | Southland Royalty Company | Houston, TX 77210 | Oil & Gas Operator | Sep 2011 |
| 39 | Southwestern Energy Prod Co | Houston, TX 77032 | Oil & Gas Operator | Jun 2015 |
| 40 | Southwestern Production Corporation | Lakewood, CO 80228 | Oil & Gas Operator | Feb 2025 |
| 41 | Spirit Energy Inc | Edmond, OK 73034 | Oil & Gas Operator | Apr 1999 |
| 42 | St. Mary Operating Company | Denver, CO 80203 | Oil & Gas Operator | Mar 2019 |
| 43 | Stag Oil Producers Inc | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 44 | Star Resources LLC | Englewood, CO 80155-5185 | Oil & Gas Operator | Dec 2013 |
| 45 | States Exploration Inc | | Oil Operator | Jul 1985 |
| 46 | Statex Petroleum Inc | Dallas, TX 75229 | Oil & Gas Operator | Dec 2000 |
| 47 | Steamboat Oil And Gas LLC | Gillette, WY 82717 | Oil Operator | Jan 2025 |
| 48 | Stellar Oil Company | Arvada, CO 80006 | Oil & Gas Operator | Dec 1998 |
| 49 | Stephens Production Company | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2025 |
| 50 | Sterling Energy Corp | Denver, CO 80202 | Oil & Gas Operator | Sep 1995 |
| 51 | Stewart Petroleum Corporation | Greenwood VIllage, CO 80111 | Oil & Gas Operator | Dec 2023 |
| 52 | Stone & Wolf LLC | Sheridan, WY 82801 | Oil & Gas Operator | Dec 2006 |
| 53 | Stone Petroleum Corporation | | Oil & Gas Operator | Dec 1996 |
| 54 | Storm Cat Energy USA Operating Corp | Denver, CO 80202 | Gas Operator | Jun 2017 |
| 55 | Stovall Oil Company | Casper, WY 82602 | Oil & Gas Operator | Aug 1998 |
| 56 | Stroud Petroleum, Inc. | Shreveport, LA 71162 | Oil & Gas Operator | Apr 2025 |
| 57 | Summit Gas Resources Inc | Sheridan, WY 82801 | Gas Operator | Dec 2023 |
| 58 | Suncor Energy Natural Gas America Inc | Greenwood VIllage, CO 80111 | Gas Operator | Feb 2010 |
| 59 | Sundance Oil Exploration Co | | Oil Operator | Mar 1986 |
| 60 | Sunshine Valley Petroleum | Casper, WY 82605 | Oil & Gas Operator | Feb 2025 |
| 61 | Swenco-Western Inc | Houston, TX 77060 | Oil & Gas Operator | Jan 1997 |
| 62 | Swepi LP | Houston, TX 77079 | Oil & Gas Operator | Jul 2020 |
| 63 | Swift Energy Company | Houston, TX 77060 | Oil & Gas Operator | Mar 2021 |