| 1 | Haber Resources Corporation | Houston, TX 77063 | Oil & Gas Operator | Mar 1999 |
| 2 | Halex Oil Corporation | Houston, TX 77057 | Oil & Gas Operator | Feb 2026 |
| 3 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 4 | Hanson Minerals Co. | Houston, TX 77042 | Oil & Gas Operator | Oct 1993 |
| 5 | Hanson Production Company | Cuero, TX 77954 | Oil & Gas Operator | Jul 2009 |
| 6 | Harper Hefte, Inc. | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Feb 2026 |
| 7 | Hart Petroleum Services, Inc | Corpus Chrsti, TX 78410 | Oil & Gas Operator | Jul 2025 |
| 8 | Harvey, Mike W. Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Aug 2003 |
| 9 | Harwood Exploration, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Aug 1995 |
| 10 | Heartland Production, Inc. | Cuero, TX 77954 | Oil & Gas Operator | Feb 2026 |
| 11 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Feb 2026 |
| 12 | Hoc Operating Co., Inc. | Houston, TX 77056 | Oil & Gas Operator | Nov 1999 |
| 13 | Holcomb Energy Corp. | Encinal, TX 78019 | Oil & Gas Operator | Dec 2013 |
| 14 | Hou-Tex, Inc. | Houston, TX 77224 | Oil & Gas Operator | Jun 2001 |
| 15 | Houston Gulf Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Feb 2026 |
| 16 | Howard Exploration, Inc. | Houston, TX 77069 | Oil & Gas Operator | Feb 2026 |
| 17 | Howard, Douglas J. | Houston, TX 77070 | Oil & Gas Operator | Mar 2008 |
| 18 | Howell Drilling, Inc. | San Antonio, TX 78230 | Oil & Gas Operator | Aug 2003 |
| 19 | HR Petroleum | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Apr 1998 |
| 20 | HRH Energy Group Incorporated | Carrollton, TX 75006 | Oil & Gas Operator | Nov 2009 |
| 21 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Feb 2026 |
| 22 | Hughes, Dan A. Company, L.P. | Beeville, TX 78104 | Oil & Gas Operator | Feb 2026 |
| 23 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Feb 2026 |
| 24 | Hunt Petroleum Corp. | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 25 | Hunt, WM. Herbert, Trust Est. | Dallas, TX 75201 | Oil & Gas Operator | Sep 1998 |
| 26 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Feb 2026 |
| 27 | Hydrocarbon Horizons, Inc. | Corpus Chrsti, TX 78473 | Oil & Gas Operator | Jun 2023 |
| 28 | Hydrocarbon Operating, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Feb 2026 |
| 29 | Hyquest Energy, Inc. | Midland, TX 79710 | Oil & Gas Operator | Mar 2015 |