| 1 | H & S Drilling Co Inc | Frazeysburg, OH 43822 | Oil & Gas Operator | Dec 2016 |
| 2 | H&M Production, Inc. | New Braunfels, TX 78132 | Oil & Gas Operator | Aug 2012 |
| 3 | Hallwood Energy Corporation | Oklahoma City, OK 73154 | Oil & Gas Operator | Feb 2005 |
| 4 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2026 |
| 5 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 6 | Hannathon Petroleum, LLC | Midland, TX 79705 | Oil & Gas Operator | Sep 2026 |
| 7 | Hanson Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2008 |
| 8 | Harkey Energy Inc. | Odessa, TX 79762 | Oil & Gas Operator | Feb 2020 |
| 9 | Headington Energy Partners, LLC | Corpus Christ, TX 78401 | Oil & Gas Operator | Sep 2026 |
| 10 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 11 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Apr 2026 |
| 12 | Henderson & Erickson, Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2026 |
| 13 | Hendrix, John H. Corporation | Midland, TX 79705 | Oil & Gas Operator | Sep 2018 |
| 14 | Henry Petroleum Corp. | Midland, TX 79703 | Oil & Gas Operator | Mar 2001 |
| 15 | Henry Petroleum LP | Midland, TX 79701 | Oil & Gas Operator | Dec 2008 |
| 16 | Henry Resources LLC | Midland, TX 79703 | Oil & Gas Operator | Sep 2026 |
| 17 | Herricks Oil Co. | San Angelo, TX 76906 | Oil & Gas Operator | Jan 2010 |
| 18 | Hexp Operating, LLC | Midland, TX 79705 | Oil & Gas Operator | Sep 2026 |
| 19 | Hibernia Resources III, LLC | Houston, TX 77056 | Oil & Gas Operator | Nov 2023 |
| 20 | Hibernia Resources IV, LLC | Houston, TX 77056 | Oil & Gas Operator | Sep 2026 |
| 21 | Highland Production Company | Midland, TX 79701 | Oil & Gas Operator | Mar 1996 |
| 22 | Highmount Expl & Prod Texas LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2014 |
| 23 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Sep 2026 |
| 24 | Hill, A G | Dallas, TX 75201 | Oil & Gas Operator | May 2008 |
| 25 | Hillside Oil & Gas, LLC | Midland, TX 79708 | Oil & Gas Operator | Apr 2016 |
| 26 | HPC Energy LLC | Midland, TX 79703 | Oil & Gas Operator | Aug 2013 |
| 27 | HPPC, Inc. | Midland, TX 79701 | Oil & Gas Operator | Sep 2025 |
| 28 | Hughes, Bob Oil Company | San Angelo, TX 76901 | Oil & Gas Operator | Jul 2011 |
| 29 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 30 | Hulsey Larry O & Co | Graham, TX 76046 | Oil & Gas Operator | Jun 2012 |
| 31 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Sep 2026 |
| 32 | Hunter Oil & Gas Co. | Bangs, TX 76823 | Oil & Gas Operator | Sep 2026 |
| 33 | Hydrocarbon Management, Inc. | San Antonio, TX 78216 | Oil & Gas Operator | Dec 1996 |