| 101 | Cordillera Energy Partners, LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Mar 2020 |
| 102 | Cordillera Energy PRTNRS III,LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2012 |
| 103 | Cordillera Texas, L.P. | Greenwood VLG, CO 80111 | Oil & Gas Operator | Sep 2008 |
| 104 | Corlena Oil Company | Amarillo, TX 79101 | Oil & Gas Operator | Dec 2025 |
| 105 | Cory, Kenneth W. | Bellaire, TX 77401 | Oil & Gas Operator | Mar 2012 |
| 106 | Cory, Kenneth W. LTD. | Bellaire, TX 77401 | Oil & Gas Operator | Dec 2025 |
| 107 | Courson Oil & Gas, Inc. | Perryton, TX 79070 | Oil & Gas Operator | Dec 2025 |
| 108 | Cox Resources Corporation | Dallas, TX 75244 | Oil & Gas Operator | Mar 2015 |
| 109 | Crawley Petroleum Corporation | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 110 | Credo Petroleum Corporation | Denver, CO 80202 | Oil & Gas Operator | Jan 2013 |
| 111 | Crescendo Resources, L.P. | Amarillo, TX 79188 | Oil & Gas Operator | Aug 2025 |
| 112 | Crest Resources Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2025 |
| 113 | Cross Timbers Operating Company | Fort Worth, TX 76102 | Oil & Gas Operator | Jun 2025 |
| 114 | Crow Creek Operating Co II LLC | Houston, TX 77252 | Oil & Gas Operator | Jul 2011 |
| 115 | Crown Energy Company | Oklahoma City, OK 73106 | Oil & Gas Operator | Aug 2025 |
| 116 | Crown Petroleum Corp. | Oklahoma City, OK 73106 | Oil & Gas Operator | Dec 2025 |
| 117 | Crusader Energy Group Inc. | Austin, TX 78746 | Oil & Gas Operator | Mar 2015 |
| 118 | Crusader Energy Group LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Mar 2015 |
| 119 | D. G. Oil Co. | Dennis, TX 76439 | Oil & Gas Operator | Dec 2025 |
| 120 | Dalf Energy LLC | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 121 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 122 | Daniels Energy | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 123 | Daniels, J.C. Energy | Pampa, TX 79066 | Oil & Gas Operator | Apr 2001 |
| 124 | Dantex Oil & Gas, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Aug 2003 |
| 125 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Aug 2025 |
| 126 | Derrick Exploration, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Jan 2003 |
| 127 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 128 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Dec 2025 |
| 129 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 130 | Diamond S Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Dec 2025 |
| 131 | Discovery Operating Inc | Midland, TX 79705 | Oil & Gas Operator | Dec 2025 |
| 132 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Dec 2025 |
| 133 | DMS Oil Company | Houston, TX 77042 | Oil & Gas Operator | Sep 2025 |
| 134 | DNR Oil And Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Oct 2025 |
| 135 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 136 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 137 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 138 | E. T. S. Enterprises, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Jul 1996 |
| 139 | Eagle Exploration Co., Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Dec 2019 |
| 140 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Dec 2025 |
| 141 | Eagle Rock Mid-Continent Op, LLC | Houston, TX 77252 | Oil & Gas Operator | Sep 2015 |
| 142 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 143 | Ehvi Exploration LLC | Denver, CO 80202 | Oil & Gas Operator | May 2025 |
| 144 | El Paso Production Company | Houston, TX 77002 | Oil & Gas Operator | Mar 2016 |
| 145 | Empire Operating, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2017 |
| 146 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 147 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Sep 2025 |
| 148 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 149 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 150 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | Aug 2025 |
| 151 | Energy Transfer Fuel, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 152 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 153 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 154 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 155 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Dec 2025 |
| 156 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 157 | Eqv Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Dec 2025 |
| 158 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 159 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 160 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 161 | Faulconer Energy, LLC | Tyler, TX 75711 | Oil & Gas Operator | Dec 2025 |
| 162 | Faulconer, Vernon E., Inc. | Tyler, TX 75711 | Oil & Gas Operator | Sep 2025 |
| 163 | Flairtex Resources, Inc. | Houston, TX 77040 | Oil & Gas Operator | Oct 1998 |
| 164 | Flow Production Company | Midland, TX 79708 | Oil & Gas Operator | Mar 2005 |
| 165 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 166 | Forestar Petroleum Corporation | Denver, CO 80202 | Oil & Gas Operator | May 2017 |
| 167 | Fortune Natural Resources Corp. | Houston, TX 77067 | Oil & Gas Operator | Dec 2003 |
| 168 | Fredonia Resources Inc. | Longview, TX 75606 | Oil & Gas Operator | Aug 2003 |
| 169 | Frontier Gas Operating Corp. | Houston, TX 77002 | Oil & Gas Operator | Jul 1998 |
| 170 | FX Energy Operating, LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2025 |
| 171 | G E Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | May 2020 |
| 172 | Gala Resources, LTD. | Graham, TX 76450 | Oil & Gas Operator | Aug 2025 |
| 173 | Gasanadarko LTD | Oklahoma City, OK 73116 | Gas Operator | May 1994 |
| 174 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 175 | Gothic Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2015 |
| 176 | Grace Petroleum Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1997 |
| 177 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 178 | Grand Resources Inc | Tulsa, OK 74137 | Oil & Gas Operator | Dec 2025 |
| 179 | Granite Operating Company | Houston, TX 77056 | Oil & Gas Operator | Nov 2012 |
| 180 | Grayhawk Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2006 |
| 181 | Grayrock Energy II, LLC | Fort Worth, TX 76101 | Oil & Gas Operator | Dec 2025 |
| 182 | Great Plains Operating, LLC. | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2014 |
| 183 | Grizzly Op Of Delaware, LLC | Houston, TX 77057 | Oil & Gas Operator | Mar 2021 |
| 184 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 185 | Guest Petroleum Incorporated | Edmond, OK 73013 | Oil & Gas Operator | Sep 2025 |
| 186 | Gunsmoke Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | May 2012 |
| 187 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 188 | H & L Operating Co., LLC | Amarillo, TX 79114 | Oil & Gas Operator | Mar 2021 |
| 189 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 190 | H-S Exploration | Gunnison, CO 81230 | Oil & Gas Operator | Dec 2025 |
| 191 | Hadaway Consult And Engineer,LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2025 |
| 192 | Hadaway Engineering Inc | Canadian, TX 79014 | Oil & Gas Operator | Jul 2015 |
| 193 | Haider Operating, LLC | Pampa, TX 79066 | Oil & Gas Operator | Dec 2025 |
| 194 | Hall Energy Co. | Oklahoma City, OK 73102 | Oil & Gas Operator | Sep 2016 |
| 195 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 196 | Hamon Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Dec 2011 |
| 197 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 198 | Hawthorn Energy Partners, LLC | Nichols Hill, OK 73116 | Oil & Gas Operator | Dec 2025 |
| 199 | Hayabusa Energy USA, LLC | Pampa, TX 79065 | Oil & Gas Operator | Dec 2025 |
| 200 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Aug 2025 |