| 101 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2025 |
| 102 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 103 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | May 2025 |
| 104 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 105 | DPMP Energy LLC | Prosper, TX 75078 | Oil & Gas Operator | Dec 2023 |
| 106 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 107 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 108 | Durham, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2016 |
| 109 | Dyersdale Production Co, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | May 2025 |
| 110 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | May 2025 |
| 111 | Eagle Rock Operating Company,LLC | Houston, TX 77252 | Oil & Gas Operator | Oct 2015 |
| 112 | Edf Trading Resources, LLC | Austin, TX 78746 | Oil & Gas Operator | Jul 2015 |
| 113 | Eex Corporation | Houston, TX 77060 | Oil & Gas Operator | Feb 2000 |
| 114 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 115 | Ellis Exploration, Inc. | Tyler, TX 75703 | Oil & Gas Operator | May 2025 |
| 116 | Enbridge G & P (East Texas) L.P. | Houston, TX 77056 | Oil & Gas Operator | Sep 2018 |
| 117 | Enbridge Pipelines (Ne Texas) LP | Houston, TX 77002 | Oil & Gas Operator | Jan 2010 |
| 118 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 119 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | Jan 2025 |
| 120 | Energy Transfer Fuel, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 121 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2025 |
| 122 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 123 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 124 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 125 | Estate Oil & Gas Corp. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2011 |
| 126 | Etoco Incorporated | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 127 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 128 | Falcon Resources, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2021 |
| 129 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 130 | Faulconer Vernon E Inc | Tyler, TX 75711 | Oil & Gas Operator | Mar 2025 |
| 131 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 132 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | May 2025 |
| 133 | Force 4 Energy Resources, Inc. | Austin, TX 78733 | Oil & Gas Operator | Aug 2005 |
| 134 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 135 | Forestar Petroleum Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2017 |
| 136 | Fortson Oil Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2020 |
| 137 | Fredonia Resources Inc. | Longview, TX 75606 | Oil & Gas Operator | Aug 2003 |
| 138 | Freestone Resources, Inc | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 139 | Frisco Energy, L.L.C. | Tulsa, OK 74105 | Oil & Gas Operator | Feb 2025 |
| 140 | Fullspike Energy LLC | Boyd, TX 76023 | Oil & Gas Operator | May 2025 |
| 141 | Gas Engine & Compressor Serv,Inc | Longview, TX 75615 | Oil & Gas Operator | Feb 2003 |
| 142 | Gilmore, Leo Oil, Inc. | Holliday, TX 76366 | Oil & Gas Operator | May 2025 |
| 143 | Goldston Oil Corporation | Houston, TX 77257 | Oil & Gas Operator | May 2025 |
| 144 | Goodrich Oil Company | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2001 |
| 145 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 146 | Grace Petroleum Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1997 |
| 147 | Grand Energy, Inc. | Dallas, TX 75248 | Oil & Gas Operator | Oct 2002 |
| 148 | Graward Operating, Inc. | Tyler, TX 75702 | Oil & Gas Operator | May 2025 |
| 149 | Grayrock Corp., The | Dallas, TX 75243 | Oil & Gas Operator | Dec 1999 |
| 150 | Green River Resources Inc. | Keystone, CO 80435 | Oil & Gas Operator | May 2025 |
| 151 | Griffin Operating, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Mar 2017 |
| 152 | H & S Production, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Mar 2004 |
| 153 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2025 |
| 154 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 155 | Harleton Oil & Gas Inc. | Tyler, TX 75710 | Oil & Gas Operator | May 2025 |
| 156 | Harman Operating Company, Inc. | Tyler, TX 75702 | Oil & Gas Operator | Dec 2007 |
| 157 | Haynie Energy Services LLC | Wortham, TX 76693 | Oil Operator | May 2025 |
| 158 | Headington Energy Corporation | Dallas, TX 75231 | Oil & Gas Operator | Aug 1992 |
| 159 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 160 | Headington Oil Company LLC | Dallas, TX 75204 | Oil & Gas Operator | Apr 2016 |
| 161 | Headington Oil Company, L.P. | Dallas, TX 75231 | Oil & Gas Operator | Mar 2008 |
| 162 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 163 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 164 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 165 | Herd Producing Company, Inc. | Tyler, TX 75711 | Oil & Gas Operator | May 2025 |
| 166 | Hereford, J. A. Industries, Inc. | Nacogdoches, TX 75961 | Oil & Gas Operator | May 2025 |
| 167 | Hibbard Energy, LP | Whitehouse, TX 75791 | Oil & Gas Operator | May 2025 |
| 168 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | May 2025 |
| 169 | Hinton Production Company | MT Pleasant, TX 75455 | Oil & Gas Operator | Aug 1995 |
| 170 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | May 2025 |
| 171 | Houston Exploration Co, The | Houston, TX 77002 | Oil & Gas Operator | Apr 2017 |
| 172 | HRB Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | May 2025 |
| 173 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 174 | Hughey, Gaylord T. SR. Oper. Co. | Tyler, TX 75711 | Oil & Gas Operator | Feb 1998 |
| 175 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | May 2025 |
| 176 | Hunt Petroleum Corporation | Dallas, TX 75201 | Oil & Gas Operator | Nov 2008 |
| 177 | Huntington Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Oct 2006 |
| 178 | Hurd Enterprises, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | May 2025 |
| 179 | Inland Oil And Gas | Nacogdoches, TX 75961 | Oil & Gas Operator | Dec 1997 |
| 180 | Ironwood Oil & Gas LLC | Houston, TX 77067 | Oil & Gas Operator | Jun 2014 |
| 181 | Jack Russell Oil, LLC | Fairfield, TX 75840 | Oil & Gas Operator | May 2025 |
| 182 | Jandar Exploration | Henderson, TX 75653 | Oil & Gas Operator | Dec 1994 |
| 183 | Jay Management Company LLC | Houston, TX 77057 | Oil & Gas Operator | May 2025 |
| 184 | Jess Energy Company | Tyler, TX 75710 | Oil & Gas Operator | Sep 1997 |
| 185 | JHP Operating, LLC | Dallas, TX 75225 | Oil & Gas Operator | May 2025 |
| 186 | Jolen Operating Company | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2025 |
| 187 | Juna Operating Co. | Corsicana, TX 75151 | Oil & Gas Operator | Dec 1996 |
| 188 | K A Ware Production Co., LLC | Pratt, KS 67124 | Oil Operator | May 2025 |
| 189 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | May 2025 |
| 190 | Karper Company, The | Graham, TX 76450 | Oil & Gas Operator | Feb 2003 |
| 191 | Karper Oil & Gas Corporation | Graham, TX 76450 | Oil & Gas Operator | May 2025 |
| 192 | Kayuga Co. | Tulsa, OK 74133 | Oil & Gas Operator | May 2025 |
| 193 | KCS Resources LLC | Houston, TX 77027 | Oil & Gas Operator | Feb 2017 |
| 194 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 195 | Key Production Company, Inc. | Longview, TX 75606 | Oil & Gas Operator | Mar 2025 |
| 196 | Killingsworth Oil Co. | Longview, TX 75606 | Oil & Gas Operator | May 2025 |
| 197 | Kilmarnock Oil Company, Inc. | Corsicana, TX 75110 | Oil & Gas Operator | May 2025 |
| 198 | Koch Midstream Services Company | Wichita, KS 67201 | Oil & Gas Operator | Oct 2000 |
| 199 | Kraker & Martin Energy, L.L.C. | Tulsa, OK 74136 | Oil & Gas Operator | Apr 2011 |
| 200 | Lacy Operations, LTD. | Longview, TX 75606 | Oil & Gas Operator | Oct 2012 |