| 1 | H & B Production | | Oil Operator | Mar 1995 |
| 2 | H & H & S Oil Producers | | Oil Operator | Jan 2025 |
| 3 | H & H Oil Co. #1 | | Oil Operator | Jan 2025 |
| 4 | H & H Oil Producers | | Oil & Gas Operator | Jan 2025 |
| 5 | H H H Oil Company | | Oil Operator | Jan 2025 |
| 6 | H. D. McCormick | | Oil & Gas Operator | Jun 2016 |
| 7 | H. E. Sutton | | Oil & Gas Operator | Jan 1990 |
| 8 | H. G. Oil Operator | | Oil Operator | Mar 2001 |
| 9 | H. J. Bonner | | Oil & Gas Operator | Aug 1991 |
| 10 | H. L. Richey | | Oil & Gas Operator | Sep 1995 |
| 11 | H.E. Sutton, Et Al | | Oil & Gas Operator | Jan 1990 |
| 12 | Haffaday Oil LLC | | Oil Operator | Jan 2025 |
| 13 | Hale Oil | | Oil & Gas Operator | Dec 2024 |
| 14 | Hale Oil Co. | | Oil & Gas Operator | Jan 2025 |
| 15 | Hall Engineering, Inc. | | Oil & Gas Operator | Jan 2007 |
| 16 | Hall-Hargraves, L.L.C. | | Oil & Gas Operator | Dec 2024 |
| 17 | Hanover Management Company | | Oil Operator | Aug 1979 |
| 18 | Hardco, Inc. | Cleveland, OH 44115 | Oil & Gas Operator | Dec 1992 |
| 19 | Hardey Co., The | Shreveport, LA 71107 | Oil & Gas Operator | Oct 2025 |
| 20 | Hardey Production Company | | Oil Operator | Dec 1998 |
| 21 | Hargraves Daughters | | Oil Operator | Mar 1992 |
| 22 | Hargraves Production, LLC | | Oil Operator | Jan 2025 |
| 23 | Harold H. Hollenshead | | Oil & Gas Operator | May 2002 |
| 24 | Harrison & Lee | | Oil Operator | Sep 1996 |
| 25 | Hart & McFarland | Vivian, LA 71082 | Oil & Gas Operator | Oct 2025 |
| 26 | Hartco Oil Co. | | Oil Operator | Jan 2025 |
| 27 | Hawk Oil Co. | Luling, TX 78648 | Oil & Gas Operator | Aug 2003 |
| 28 | Hawkeye Drilling Co. | Waskom, TX 75692 | Oil & Gas Operator | Feb 2023 |
| 29 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 30 | HDS Production | | Oil Operator | Mar 1998 |
| 31 | Helena Production Corp | | Oil & Gas Operator | Dec 1991 |
| 32 | Henergy Oil & Gas LLC | | Oil Operator | Jan 2025 |
| 33 | Herbert J. Schmitz | | Oil & Gas Operator | Dec 1987 |
| 34 | Herbst Resources, Inc. | Mandeville, LA 70448 | Oil & Gas Operator | Aug 2003 |
| 35 | Heritage Energy Company | | Oil & Gas Operator | Jun 2001 |
| 36 | Herman Fields | | Oil & Gas Operator | May 1989 |
| 37 | Herring Production Co | | Oil & Gas Operator | Mar 1992 |
| 38 | High-Hope Oil And Gas, Inc | | Oil & Gas Operator | Mar 2017 |
| 39 | Highlands Operating Co., Inc. | | Oil & Gas Operator | May 1990 |
| 40 | Hilliard Petroleum Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Sep 2009 |
| 41 | Hobbs Oil Co. | | Oil Operator | Dec 1999 |
| 42 | Hobbs Production LLC | | Oil Operator | Mar 2023 |
| 43 | Hollenshead Oil Co. | | Oil & Gas Operator | Mar 1992 |
| 44 | Hosston Oil Inc. | | Oil Operator | Dec 1993 |
| 45 | Howell & Sandlin, Inc. | Marshall, TX 75671 | Oil & Gas Operator | Jan 2001 |
| 46 | Hubco Exploration Inc. | Houston, TX 77073 | Oil & Gas Operator | Sep 2002 |
| 47 | Huey Dean | | Oil Operator | Oct 2000 |
| 48 | Huggs Incorporated, Et Al | | Oil & Gas Operator | Feb 1998 |
| 49 | Hughes Supplies, Inc. | Greenwood, LA 71033 | Oil & Gas Operator | Jul 2019 |
| 50 | Hunt Oil Co., Et Al | | Oil & Gas Operator | Nov 1992 |
| 51 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 52 | Hurley Oil And Gas Company | | Oil & Gas Operator | Jan 1997 |
| 53 | Hurley Petroleum Corporation | Baton Rouge, LA 70821 | Oil & Gas Operator | Feb 2000 |
| 54 | Hutson Oil Co. | | Oil & Gas Operator | Nov 2024 |
| 55 | Hyman Muslow | | Oil Operator | Jun 1995 |