| 1 | H & O Operating Co | Odessa, TX 79764 | Oil & Gas Operator | Mar 2008 |
| 2 | H&P Oil & Gas LLC | Mertzon, TX 76941 | Oil & Gas Operator | Apr 2026 |
| 3 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 4 | Hamill Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 1999 |
| 5 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Apr 2026 |
| 6 | Hampton Resources Corporation | Houston, TX 77010 | Oil & Gas Operator | Mar 1996 |
| 7 | Hane Operating, Inc. | Santa Anna, TX 76878 | Oil & Gas Operator | Sep 2005 |
| 8 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 9 | Hannathon Petroleum II, LLC | Midland, TX 79705 | Oil & Gas Operator | Apr 2026 |
| 10 | Hannathon Petroleum, LLC | Midland, TX 79705 | Oil & Gas Operator | Apr 2026 |
| 11 | Hanson Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2008 |
| 12 | Harding Well Service Co. | Coahoma, TX 79511 | Oil & Gas Operator | Aug 2003 |
| 13 | Harmony Drilling Company, Inc. | Denver, CO 80222 | Oil & Gas Operator | Nov 2016 |
| 14 | Hartoil Corporation | Post, TX 79356 | Oil & Gas Operator | Apr 2026 |
| 15 | Headington Energy Partners, LLC | Corpus Christ, TX 78401 | Oil & Gas Operator | Apr 2026 |
| 16 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 17 | Hendrix, John H. Corporation | Midland, TX 79705 | Oil & Gas Operator | Sep 2018 |
| 18 | Henry Petroleum LP | Midland, TX 79701 | Oil & Gas Operator | Dec 2008 |
| 19 | Hexp Operating, LLC | Midland, TX 79705 | Oil & Gas Operator | Apr 2026 |
| 20 | High Sky Oil & Gas | Midland, TX 79705 | Oil & Gas Operator | Jun 2008 |
| 21 | Hillside Oil & Gas, LLC | Midland, TX 79708 | Oil & Gas Operator | Apr 2016 |
| 22 | Holly Petroleum, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2008 |
| 23 | Horizon Oil & Gas Co. | Dallas, TX 75221 | Oil & Gas Operator | Jan 2005 |
| 24 | Houston Oil & Minerals Corp. | Houston, TX 77002 | Oil & Gas Operator | Aug 1996 |
| 25 | HRB Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | Apr 2026 |
| 26 | Hrubetz Operating Company | Dallas, TX 75225 | Oil & Gas Operator | Feb 1999 |
| 27 | Huff, Jack | Midland, TX 79710 | Oil & Gas Operator | Dec 2004 |
| 28 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 29 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Apr 2026 |
| 30 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Apr 2026 |
| 31 | Hurley Petroleum Corporation | Baton Rouge, LA 70821 | Oil & Gas Operator | Feb 2000 |