| 101 | H&P Operating | Megargel, TX 76370 | Oil & Gas Operator | Jan 2015 |
| 102 | H&S Production, LLC | | Oil Operator | Nov 2024 |
| 103 | H-30 Incorporate | | Oil & Gas Operator | Nov 1990 |
| 104 | H-30, Inc. | Wichita, KS 67202 | Gas Operator | Oct 2006 |
| 105 | H-40 Drilling, Inc. | Medicine Lodge, KS 67104 | Gas Operator | Mar 2025 |
| 106 | H-5 Service | Plainville, KS 67663 | Oil Operator | May 1989 |
| 107 | H-D Oilfield Service, Inc. | Bazine, KS 67516 | Oil Operator | Feb 2025 |
| 108 | H-M Resource Management, Inc. | Houston, TX 77055 | Oil & Gas Operator | Feb 2023 |
| 109 | H-Petro-R Inc | Edmond, OK 73013 | Oil & Gas Operator | Apr 2025 |
| 110 | H-S Exploration | Perryton, TX 79070 | Oil & Gas Operator | Jul 2025 |
| 111 | H-Two-O Investments | Iowa Park, TX 76367 | Oil Operator | Sep 2019 |
| 112 | H. & H. Development Co. | | Gas Operator | Aug 2019 |
| 113 | H. & J. Drilling Company | Fort Worth, TX 76114 | Oil & Gas Operator | Aug 2003 |
| 114 | H. & L. Oil Company | Midland, TX 79707 | Oil & Gas Operator | Mar 2005 |
| 115 | H. & N. Operating Co., Inc. | | Oil & Gas Operator | Oct 1997 |
| 116 | H. A. Harper | | Oil Operator | Dec 1982 |
| 117 | H. B. McCullough | | Oil Operator | Oct 2004 |
| 118 | H. Bryan Poff, LLC | Cedar Park, TX 78613 | Oil & Gas Operator | Oct 2018 |
| 119 | H. C. Oil Co. | Weatherford, TX 76085 | Oil & Gas Operator | Jul 2025 |
| 120 | H. D. Investments | Breckenridge, TX 76424 | Oil & Gas Operator | Mar 2025 |
| 121 | H. D. McCormick | | Oil & Gas Operator | Jun 2016 |
| 122 | H. E. Sutton | | Oil & Gas Operator | Jan 1990 |
| 123 | H. G. Oil Operator | | Oil Operator | Mar 2001 |
| 124 | H. H. Blair Oil Company, Inc. | Atlanta, KS 67008 | Oil Operator | Dec 2009 |
| 125 | H. I. M. Producers | Graham, TX 76450 | Oil & Gas Operator | May 1999 |
| 126 | H. I., Inc. | Liberal, KS 67901 | Oil & Gas Operator | Feb 2012 |
| 127 | H. J. Bonner | | Oil & Gas Operator | Aug 1991 |
| 128 | H. K. Beebe | | Oil Operator | Jan 1990 |
| 129 | H. L. Brown, Jr. | Midland, TX 79702 | Oil & Gas Operator | May 2001 |
| 130 | H. L. Hunt | | Oil & Gas Operator | Jun 1980 |
| 131 | H. L. McKee & J. P. McKee Jr. | | Gas Operator | Mar 2023 |
| 132 | H. L. Richey | | Oil & Gas Operator | Sep 1995 |
| 133 | H. O. Strickler Operator | | Oil & Gas Operator | Dec 1993 |
| 134 | H. Olsen & Sons Contractors, Inc. | Forestville, NY 14062 | Gas Operator | Dec 2024 |
| 135 | H. Proler-Luffey Gas Corp. | | Gas Operator | Apr 1979 |
| 136 | H. T. Hilliard & Co. | | Oil & Gas Operator | Dec 1999 |
| 137 | H. W. Reynolds Jr. | | Gas Operator | Dec 1984 |
| 138 | H.A.N. Operating Incorporated | Clyde, TX 79510 | Oil & Gas Operator | Aug 2016 |
| 139 | H.E. Sutton, Et Al | | Oil & Gas Operator | Jan 1990 |
| 140 | H.E.R. Operating, LLC | Silsbee, TX 77656 | Oil & Gas Operator | Jul 2025 |
| 141 | H.E.X.T. Operating, LTD. | Buna, TX 77612 | Oil Operator | Mar 2024 |
| 142 | H.I.T. Resources, Inc. | Arkansas City, KS 67005 | Oil Operator | Jan 2007 |
| 143 | H.K.E. | Stafford, TX 77497 | Oil & Gas Operator | Jul 2025 |
| 144 | H.L. Clark Oil Company LLC | Whitesboro, TX 76273 | Oil Operator | Jul 2025 |
| 145 | H.L. Hall & Sons LLC | | Oil & Gas Operator | Dec 2011 |
| 146 | H.L.Hawkins &H.L.Hawkins, Jr. | | Oil & Gas Operator | Feb 1989 |
| 147 | H.L.S. Energy Co., Inc. | Uvalde, TX 78801 | Oil & Gas Operator | Aug 2003 |
| 148 | H.P. Slagel Producing Co., LLC | San Angelo, TX 76902 | Oil Operator | Jul 2025 |
| 149 | H.T. Olsen Oil & Gas Operations | | Oil & Gas Operator | May 2025 |
| 150 | H2oil Services LLC | | Oil Operator | Jun 2025 |
| 151 | H2ok LLC | Marble Falls, TX 78654 | Oil & Gas Operator | Apr 2025 |
| 152 | H2ox Operating LLC | Tulsa, OK 74103 | Oil Operator | Apr 2025 |
| 153 | H3 Oil & Gas | | Oil & Gas Operator | Mar 2025 |
| 154 | H3 Operating, LLC | Springtown, TX 76082 | Oil & Gas Operator | May 2020 |
| 155 | Ha Goal Inc | Indiana, PA 15701-2664 | Oil & Gas Operator | Dec 2018 |
| 156 | Ha.P.C. Oil, Inc. | Gonzales, TX 78629 | Oil & Gas Operator | Aug 2006 |
| 157 | Haack Operating Company | Tulsa, OK 74137 | Oil Operator | Mar 2025 |
| 158 | Haas John L | | Oil Operator | Dec 2009 |
| 159 | Haas Petroleum, LLC | Prairie VIllage, KS 66208 | Oil Operator | Mar 2025 |
| 160 | Haas, C. F. Oil & Gas Inc. | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Jul 2025 |
| 161 | Haas, Mark L. | Kansas City, MO 67112 | Oil Operator | Feb 2013 |
| 162 | Haass Ranch Oil Company, LLC | Castroville, TX 78009 | Oil Operator | Jul 2025 |
| 163 | Habanero Oil & Gas Operating,LLC | Austin, TX 78701 | Oil & Gas Operator | Feb 2018 |
| 164 | Haber Resources Corporation | Houston, TX 77063 | Oil & Gas Operator | Mar 1999 |
| 165 | Habetz Oilfield Saltwater Ser, Inc | | Oil Operator | Dec 2024 |
| 166 | Habit Petroleum | | Oil Operator | Dec 2009 |
| 167 | Habit Petroleum, LLC | Hays, KS 67601 | Oil Operator | Mar 2025 |
| 168 | Hackberry Production, Inc. | | Oil Operator | Mar 1988 |
| 169 | Hacker Brothers Oil Company, Inc | Muenster, TX 76252 | Oil & Gas Operator | May 2004 |
| 170 | Hacker Brothers Well Service,Inc | Muenster, TX 76252 | Oil & Gas Operator | Jul 2025 |
| 171 | Hacker, Freddie J. | Muenster, TX 76252 | Oil & Gas Operator | Dec 2012 |
| 172 | Hacker, Jack | Coats, KS 67028 | Oil & Gas Operator | Mar 2025 |
| 173 | Hackley Okla Inc | | Oil & Gas Operator | Aug 1992 |
| 174 | Had-A-Call Oil | | Oil Operator | Feb 2017 |
| 175 | Hadaway Consult And Engineer,LLC | Canadian, TX 79014 | Oil & Gas Operator | Jul 2025 |
| 176 | Hadaway Consulting And Engineering LLC | Canadian, TX 79014 | Oil & Gas Operator | May 2025 |
| 177 | Hadaway Engineering Inc | Canadian, TX 79014 | Oil & Gas Operator | Jul 2015 |
| 178 | Hadco LTD | Ardmore, OK 73401-6929 | Oil & Gas Operator | Mar 2015 |
| 179 | Haddad & Brooks Inc | Washington, PA 15301 | Oil & Gas Operator | Dec 2018 |
| 180 | Haddad Boynton, LLC | Jonesville, TX 75659 | Oil Operator | Jul 2025 |
| 181 | Hadden, Pennell & Rohret | Lakewood, CO 80228 | Oil Operator | Nov 1994 |
| 182 | Haddock, Jack L. | Hays, KS 67601 | Oil Operator | Nov 2024 |
| 183 | Haddox Johnny C | Okemah, OK 74859-0254 | Oil Operator | Apr 2020 |
| 184 | Haddox Petroleum Corp | | Gas Operator | Dec 2010 |
| 185 | Hadley Oil | Nocona, TX 76255 | Oil Operator | Jan 2014 |
| 186 | Hadley Oil Company, LLC | Nocona, TX 76255 | Oil Operator | Jul 2025 |
| 187 | Hadley/Jackson Energy LLC | Lake Forest, IL 60045 | Oil & Gas Operator | May 2025 |
| 188 | Hadson Energy Resources Corp. | Houston, TX 77056 | Oil & Gas Operator | Dec 1994 |
| 189 | Hadson Petro USA Inc | | Oil & Gas Operator | Nov 2016 |
| 190 | Hadson Petroleum | | Oil Operator | Sep 1988 |
| 191 | Hadson Petroleum (USA), Inc. | | Oil & Gas Operator | Dec 1992 |
| 192 | Hadson Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2015 |
| 193 | Haessly Hardwood Lumber Inc | Marietta, OH 45750 | Oil & Gas Operator | Dec 2024 |
| 194 | Hafer Run Enterprise | Independence, KS 67301 | Oil Operator | Oct 1997 |
| 195 | Haffaday Oil LLC | | Oil Operator | Jan 2025 |
| 196 | Haffner Dan | Hoxie, KS 67740 | Oil Operator | Mar 2025 |
| 197 | Hagan, IVan - All-Kin Oil Co | | Oil Operator | Dec 2023 |
| 198 | Hager Gas Co | Danville, WV 25053 | Gas Operator | Dec 2010 |
| 199 | Haggard Operating Group/Oil | Atascosa, TX 78002 | Oil & Gas Operator | Jul 2025 |
| 200 | Haggard, E. A. | Graham, TX 76450 | Oil & Gas Operator | Apr 2001 |