| 1901 | H. E. Sutton | | Oil & Gas Operator | Jan 1990 |
| 1902 | H. G. Oil Operator | | Oil Operator | Mar 2001 |
| 1903 | H. J. Bonner | | Oil & Gas Operator | Aug 1991 |
| 1904 | H. K. Beebe | | Oil Operator | Jan 1990 |
| 1905 | H. L. Brown, Jr. | Midland, TX 79702 | Oil & Gas Operator | May 2001 |
| 1906 | H. L. McKee & J. P. McKee Jr. | | Gas Operator | Mar 2023 |
| 1907 | H. L. Richey | | Oil & Gas Operator | Oct 1995 |
| 1908 | H. Proler-Luffey Gas Corp. | | Gas Operator | Apr 1979 |
| 1909 | H.E. Sutton, Et Al | | Oil & Gas Operator | Jan 1990 |
| 1910 | H.L.Hawkins &H.L.Hawkins, Jr. | | Oil & Gas Operator | Feb 1989 |
| 1911 | Habetz Oilfield Saltwater Ser, Inc | | Oil Operator | Jan 2024 |
| 1912 | Hackberry Production, Inc. | | Oil Operator | Mar 1988 |
| 1913 | Haddox Petroleum Corp | | Gas Operator | Dec 2010 |
| 1914 | Hadson Energy Resources Corp. | Houston, TX 77056 | Oil & Gas Operator | Dec 1994 |
| 1915 | Hadson Petroleum (USA), Inc. | | Oil & Gas Operator | Dec 1992 |
| 1916 | Hal Oil & Gas Co., Inc. | | Oil & Gas Operator | Apr 1993 |
| 1917 | Haland Operating Company, LLC | | Oil & Gas Operator | Jul 2018 |
| 1918 | Halbouty-Reserve | | Oil & Gas Operator | Sep 1987 |
| 1919 | Halbouty-Reserve-Pel-Tex | | Oil & Gas Operator | May 1985 |
| 1920 | Halcon Louisiana Operating, LP | | Oil & Gas Operator | Sep 2017 |
| 1921 | Halcon Resources Operating, Inc. | Tulsa, OK 74135 | Oil & Gas Operator | Dec 2013 |
| 1922 | Hale Oil | | Oil & Gas Operator | Dec 2023 |
| 1923 | Hale Oil Co. | | Oil & Gas Operator | Jan 2024 |
| 1924 | Hall Engineering, Inc. | | Oil & Gas Operator | Jan 2007 |
| 1925 | Hall-Hargraves, LLC | Oil City, LA 71061 | Oil & Gas Operator | Dec 2023 |
| 1926 | Hall-Houston Oil Company | Houston, TX 77002 | Oil & Gas Operator | Oct 2002 |
| 1927 | Hallador Petroleum Company | | Oil & Gas Operator | Feb 1992 |
| 1928 | Hallar Enterprises, Inc. | | Oil Operator | Sep 2007 |
| 1929 | Halliburton Operating Company | Plano, TX 75093 | Oil & Gas Operator | Apr 2024 |
| 1930 | Hallmark Oil And Gas Co., Inc. | | Oil & Gas Operator | Dec 2023 |
| 1931 | Hallwell Gas & Oil Co. | | Oil & Gas Operator | Sep 1985 |
| 1932 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Dec 2023 |
| 1933 | Hallwood Petroleum, LLC | Dallas, TX 75219 | Oil & Gas Operator | Jan 2010 |
| 1934 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 1935 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Apr 2024 |
| 1936 | Hamon Oil Company | | Oil & Gas Operator | Aug 1985 |
| 1937 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 1938 | Hampton Resources Corporation | Houston, TX 77010 | Oil & Gas Operator | Mar 1996 |
| 1939 | Hanover Management Company | | Oil Operator | Aug 1979 |
| 1940 | Hansen Oil Corporation | Shreveport, LA 71106 | Oil Operator | Apr 2003 |
| 1941 | Hanson Natural Resources Co. | | Oil & Gas Operator | Nov 1991 |
| 1942 | Hanvey Production Co., Inc. | Roanoke, TX 76262 | Oil & Gas Operator | Nov 2012 |
| 1943 | Harbert Energy Corp | Irving, TX 75015-2510 | Oil & Gas Operator | Feb 1993 |
| 1944 | Harbert Energy Corp/Gulf Coast | | Oil & Gas Operator | Dec 1991 |
| 1945 | Harbor Operating, LLC | | Oil & Gas Operator | Dec 1999 |
| 1946 | Harbor Petroleum, LLC | Granbury, TX 76049 | Oil & Gas Operator | Apr 2024 |
| 1947 | Harcor Exploration Inc. | | Oil Operator | Aug 1989 |
| 1948 | Hardco, Inc. | Cleveland, OH 44115 | Oil & Gas Operator | Dec 1992 |
| 1949 | Hardey Co., The | Shreveport, LA 71107 | Oil & Gas Operator | Apr 2024 |
| 1950 | Hardey Production Company | | Oil Operator | Dec 1998 |
| 1951 | Hardy Oil & Gas USA Inc. | Houston, TX 77079 | Oil & Gas Operator | Jun 1996 |
| 1952 | Hargraves Daughters | | Oil Operator | Mar 1992 |
| 1953 | Hargraves Production, LLC | | Oil Operator | Jan 2024 |
| 1954 | Harleton Oil & Gas Inc. | Tyler, TX 75710 | Oil & Gas Operator | Apr 2024 |
| 1955 | Harold H. Hollenshead | | Oil & Gas Operator | May 2002 |
| 1956 | Harrison & Lee | | Oil Operator | Sep 1996 |
| 1957 | Harry L. Neeb | | Oil Operator | May 1985 |
| 1958 | Hart & McFarland | Vivian, LA 71082 | Oil & Gas Operator | Apr 2024 |
| 1959 | Hartco Oil Co. | | Oil Operator | Jan 2024 |
| 1960 | Harter Oil Company | | Oil & Gas Operator | Apr 2011 |
| 1961 | Harvard Investments, Inc. | | Oil & Gas Operator | Oct 2002 |
| 1962 | Harvest Oil & Gas, LLC | | Oil & Gas Operator | Feb 2012 |
| 1963 | Harvest Petroleum Inc. | Frisco, TX 75033 | Oil & Gas Operator | Apr 2024 |
| 1964 | Harvey Broyles | | Oil & Gas Operator | May 2012 |
| 1965 | Harvey Broyles & Munoco Co. | | Oil & Gas Operator | Jan 2002 |
| 1966 | Harvey Broyles, Et Al | | Gas Operator | Nov 1985 |
| 1967 | Hassie Hunt Expl. Company | Dallas, TX 75201 | Oil & Gas Operator | Aug 2008 |
| 1968 | Haw Corporation | | Oil Operator | Dec 1979 |
| 1969 | Hawk Oil Co. | Luling, TX 78648 | Oil & Gas Operator | Aug 2003 |
| 1970 | Hawkeye Drilling Co. | Waskom, TX 75692 | Oil & Gas Operator | Feb 2023 |
| 1971 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 1972 | Hawthorne Oil And Gas Corp. | Houston, TX 77227 | Oil & Gas Operator | Sep 1993 |
| 1973 | Hawthorne-Tipco | | Oil & Gas Operator | Oct 1978 |
| 1974 | HC Resources, Inc. | | Oil & Gas Operator | Jul 2011 |
| 1975 | HCW Exploration, Inc. | | Oil & Gas Operator | Jun 1986 |
| 1976 | HDS Production | | Oil Operator | Mar 1998 |
| 1977 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 1978 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 1979 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 1980 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 1981 | Headwaters Oil Company | | Oil & Gas Operator | Oct 1981 |
| 1982 | Hebert & Rucks L.L.C. | | Oil & Gas Operator | May 2002 |
| 1983 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 1984 | Held By Production, Inc. | Houston, TX 77251 | Oil & Gas Operator | May 1996 |
| 1985 | Helena Production Corp | | Oil & Gas Operator | Dec 1991 |
| 1986 | Helis Oil & Gas Company, L.L.C. | New Orleans, LA 70130 | Oil & Gas Operator | Oct 2023 |
| 1987 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Dec 2023 |
| 1988 | Hemco Development, LLC | Dallas, TX 75201 | Oil & Gas Operator | Nov 2020 |
| 1989 | Hemus, Inc. | Bellaire, TX 77401 | Oil & Gas Operator | Sep 1994 |
| 1990 | Henderson Oil & Gas | | Oil Operator | Sep 1990 |
| 1991 | Henderson Pet Corp Of Delaware | | Oil & Gas Operator | Nov 2019 |
| 1992 | Henderson Petroleum Corp | San Angelo, TX 76906 | Oil & Gas Operator | Jul 2013 |
| 1993 | Henergy Oil & Gas LLC | | Oil Operator | Jan 2024 |
| 1994 | Henry Production Company, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Sep 2019 |
| 1995 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 1996 | Herbert J. Schmitz | | Oil & Gas Operator | Dec 1987 |
| 1997 | Herbst Resources, Inc. | Mandeville, LA 70448 | Oil & Gas Operator | Aug 2003 |
| 1998 | Herd Producing Company, Inc. | Tyler, TX 75711 | Oil & Gas Operator | Apr 2024 |
| 1999 | Heritage Energy Company | | Oil & Gas Operator | Jun 2001 |
| 2000 | Heritage Operating Co., Inc. The | Stafford, TX 77497 | Oil & Gas Operator | May 1997 |