| 1 | H & S Production, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Mar 2004 |
| 2 | H&G Petroleum Corporation | Midland, TX 79710 | Oil & Gas Operator | Dec 2024 |
| 3 | H-M Resource Management, Inc. | Houston, TX 77055 | Oil & Gas Operator | Feb 2023 |
| 4 | Hale Oil & Gas Properties | Graham, TX 76450 | Oil & Gas Operator | Jul 1997 |
| 5 | Halliburton Operating Company | Plano, TX 75093 | Oil & Gas Operator | Dec 2024 |
| 6 | Halvey Energy Co. | Midland, TX 79702 | Oil & Gas Operator | Oct 2004 |
| 7 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Dec 2024 |
| 8 | Hanson Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2008 |
| 9 | Harding Company | Dallas, TX 75244 | Oil & Gas Operator | Jan 2015 |
| 10 | Harken Exploration Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2008 |
| 11 | Harwood Exploration, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Aug 1995 |
| 12 | Hastings, J. W. Oil Co. | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2010 |
| 13 | Hawkins, B. O. | Aspermont, TX 79502 | Oil & Gas Operator | Dec 2024 |
| 14 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 15 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 16 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 17 | Heights Energy Corporation | Plano, TX 75026 | Oil & Gas Operator | Dec 2024 |
| 18 | Henderson & Erickson, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2024 |
| 19 | Henderson Petroleum Corp | San Angelo, TX 76906 | Oil & Gas Operator | Jul 2013 |
| 20 | Henry Petroleum Corp. | Midland, TX 79703 | Oil & Gas Operator | Mar 2001 |
| 21 | Henson Exploration, L.P. | Abilene, TX 79608 | Oil & Gas Operator | Dec 2024 |
| 22 | Herring, Ray | Graham, TX 76450 | Oil & Gas Operator | Jul 2014 |
| 23 | Hexagon Oil And Gas Inc. | Fort Worth, TX 76132 | Oil & Gas Operator | Dec 2024 |
| 24 | HGN Operating Co Inc | Abilene, TX 79604 | Oil & Gas Operator | Jul 2014 |
| 25 | HGN Operating I, LLC | Abilene, TX 79604 | Oil & Gas Operator | Dec 2024 |
| 26 | Highmount Expl & Prod Texas LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2014 |
| 27 | Hodges & Hodges Productions | Anson, TX 79501 | Oil & Gas Operator | Aug 2003 |
| 28 | Hofco, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Dec 2024 |
| 29 | Holden Energy Corporation | Ardmore, OK 73401 | Oil & Gas Operator | Mar 2015 |
| 30 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 31 | Houghton Oil & Gas, Inc. | Midland, TX 79701 | Oil & Gas Operator | Mar 2009 |
| 32 | Howle Operating Account, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 1999 |
| 33 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2024 |
| 34 | Hunter Brothers | Wichita Falls, TX 76302 | Oil & Gas Operator | Jul 2007 |
| 35 | Hurst Oil & Gas, Inc. | Hillsboro, TX 76645 | Oil & Gas Operator | Dec 2024 |