| 1 | O & O Operators, LLC. | Fate, TX 75132 | Oil & Gas Operator | Feb 2026 |
| 2 | O'Brien, George H. Jr. | Midland, TX 79701 | Oil & Gas Operator | Jun 1994 |
| 3 | O'Ryan Oil And Gas | Odessa, TX 79768 | Oil & Gas Operator | Feb 2026 |
| 4 | O.G.P. Operating, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Feb 2026 |
| 5 | Occidental Energy Marketing, Inc. | Houston, TX 77227 | Gas Operator | Sep 2015 |
| 6 | Occidental Permian LTD. | Houston, TX 77046 | Oil & Gas Operator | Feb 2026 |
| 7 | Octane Energy Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Feb 2026 |
| 8 | Oden, Robin H., Inc. | Midland, TX 79702 | Oil & Gas Operator | Apr 1994 |
| 9 | Ogris Operating, LLC | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 10 | Ogs Operating Company, Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2008 |
| 11 | Oil Producers, Inc. Of Kansas | Wichita, KS 67206 | Oil & Gas Operator | Feb 2026 |
| 12 | Ojb, Inc. | Buda, TX 78610 | Oil & Gas Operator | Mar 2013 |
| 13 | Oklahoma Oil Company | Dallas, TX 75206 | Oil & Gas Operator | Aug 2013 |
| 14 | Oklahoma RB Operating Company | Midland, TX 79701 | Oil & Gas Operator | Jan 1998 |
| 15 | Olsen Energy Inc. | Boerne, TX 78006 | Oil & Gas Operator | Feb 2026 |
| 16 | Omega Energy Corp. | Graham, TX 76450 | Oil & Gas Operator | Feb 2026 |
| 17 | Orbit Crude, Inc. | Midland, TX 79710 | Oil & Gas Operator | Feb 2026 |
| 18 | Osborn Heirs Co | San Antonio, TX 78217 | Oil & Gas Operator | Dec 2025 |
| 19 | Osborn,W.B. Oil & Gas Operations | San Antonio, TX 78217 | Oil & Gas Operator | Feb 2026 |
| 20 | Otb Operating, LLC | Stanton, TX 79782 | Oil & Gas Operator | Feb 2026 |
| 21 | Overton Park Oil & Gas LP | Fort Worth, TX 76109 | Oil & Gas Operator | Feb 2026 |
| 22 | Owens Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 23 | Oxy USA Inc | Houston, TX 77046 | Oil & Gas Operator | Feb 2026 |
| 24 | Oxy USA WTP LP | Houston, TX 77046 | Oil & Gas Operator | Feb 2026 |
| 25 | Oz Gas Corporation | Tomball, TX 77377 | Gas Operator | Feb 2026 |
| 26 | Ozark Exploration, Inc. | Dallas, TX 75205 | Oil & Gas Operator | Feb 2026 |
| 27 | Oztx Oil & Gas, L.L.C. | Ozona, TX 76943 | Oil & Gas Operator | Feb 2026 |