| 1 | H & S Production, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Mar 2004 |
| 2 | Hadaway Consult And Engineer,LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2024 |
| 3 | Halliburton Operating Company | Plano, TX 75093 | Oil & Gas Operator | Dec 2024 |
| 4 | Halvey Energy Co. | Midland, TX 79702 | Oil & Gas Operator | Oct 2004 |
| 5 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 6 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Dec 2024 |
| 7 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 8 | Hanson Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2008 |
| 9 | Hastings, J. W. Oil Co. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2010 |
| 10 | Hce Operating LLC | Smyer, TX 79367 | Oil & Gas Operator | Dec 2024 |
| 11 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 12 | Henderson & Erickson, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2024 |
| 13 | Henson Exploration, L.P. | Abilene, TX 79608 | Oil & Gas Operator | Dec 2024 |
| 14 | HGN Operating I, LLC | Abilene, TX 79604 | Oil & Gas Operator | Dec 2024 |
| 15 | High Island Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Jun 2017 |
| 16 | Hofco, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2024 |
| 17 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Dec 2024 |
| 18 | Howell Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Oct 2015 |
| 19 | Hughes, Dan A. Company | Beeville, TX 78104 | Oil & Gas Operator | May 2006 |
| 20 | Hughes, Dan A. Company, L.P. | Beeville, TX 78104 | Oil & Gas Operator | Dec 2024 |
| 21 | HW Operating, LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2024 |