| 1 | H & O Operating Co | Odessa, TX 79764 | Oil & Gas Operator | Mar 2008 |
| 2 | H & W Oil Company, Incorporated | Palm Desert, CA 92255 | Oil Operator | Nov 2017 |
| 3 | H&M Production, Inc. | New Braunfels, TX 78132 | Oil & Gas Operator | Aug 2012 |
| 4 | H.D. Smith, Inc. | Waller, TX 77484 | Oil Operator | Oct 2025 |
| 5 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 6 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 7 | Hannathon Petroleum, LLC | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 8 | Hanson Corporation | New Braunfels, TX 78132 | Oil & Gas Operator | Mar 2008 |
| 9 | Hanson Operating Company Inc | Roswell, NM 88202 | Oil & Gas Operator | Jul 2025 |
| 10 | Hanvey, Don H. Oil Interests Inc | Cisco, TX 76437 | Oil & Gas Operator | Oct 2025 |
| 11 | Harrison Interests, LTD. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 12 | Hartel, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Aug 1997 |
| 13 | Harter, Ron | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 14 | Harvard Petroleum Corporation | Roswell, NM 88201 | Oil & Gas Operator | Dec 2004 |
| 15 | Harvest Petroleum Inc. | Frisco, TX 75033 | Oil & Gas Operator | Oct 2025 |
| 16 | Hat Oil & Gas, Inc. | Slaton, TX 79364 | Oil & Gas Operator | Feb 2002 |
| 17 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 18 | HCM | Dallas, TX 75206 | Oil & Gas Operator | Mar 2015 |
| 19 | Headline Resources, Inc. | Richardson, TX 75080 | Oil & Gas Operator | Aug 1997 |
| 20 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jun 2025 |
| 21 | Henderson & Erickson, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 22 | Hendon WM E. Jr. Rev LVNG Trust | Everett, WA 98208 | Oil & Gas Operator | Oct 2025 |
| 23 | Hendrix, John H. Corporation | Midland, TX 79705 | Oil & Gas Operator | Sep 2018 |
| 24 | Henry Petroleum Corp. | Midland, TX 79703 | Oil & Gas Operator | Mar 2001 |
| 25 | Henry Petroleum LP | Midland, TX 79701 | Oil & Gas Operator | Dec 2008 |
| 26 | Henry Resources LLC | Midland, TX 79703 | Oil & Gas Operator | Oct 2025 |
| 27 | Herbig Oil & Gas Co. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 28 | Herbig, J F | Midland, TX 79701 | Oil & Gas Operator | Mar 1998 |
| 29 | Hewitt, Alan P. | Midland, TX 79702 | Oil & Gas Operator | Aug 1997 |
| 30 | Hicon Gas Producers, Inc. | New York, NY 10110 | Oil & Gas Operator | Oct 1999 |
| 31 | High Sky Partners LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2015 |
| 32 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | Oct 2025 |
| 33 | Highmount Expl & Prod Texas LLC | Houston, TX 77002 | Oil & Gas Operator | Sep 2014 |
| 34 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 35 | Hilliard Oil & Gas Inc | New Orleans, LA 70112 | Oil & Gas Operator | May 2001 |
| 36 | Hillin Prod. Co. | Odessa, TX 79760 | Oil & Gas Operator | Apr 2002 |
| 37 | Hillin-Simon Oil Company | Houston, TX 77079 | Oil & Gas Operator | Mar 2013 |
| 38 | Hillside Oil & Gas, LLC | Midland, TX 79708 | Oil & Gas Operator | Apr 2016 |
| 39 | HK Energy Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2023 |
| 40 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Oct 2025 |
| 41 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Oct 2025 |
| 42 | Huff, Jack | Midland, TX 79710 | Oil & Gas Operator | Dec 2004 |
| 43 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 44 | Huntington Energy LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 45 | Huntington Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2006 |
| 46 | Hybrid Operating, Incorporated | Carlsbad, CA 92009 | Oil & Gas Operator | Oct 2025 |