| 101 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 102 | Deep Reef Industries | Amarillo, TX 79101 | Oil & Gas Operator | Jan 2004 |
| 103 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 104 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 105 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 106 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 107 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Oct 2025 |
| 108 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 109 | Draco Production Company | Tulsa, OK 74133 | Oil & Gas Operator | Jul 2012 |
| 110 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 111 | Duncan Energy Company | Denver, CO 80202 | Oil & Gas Operator | Mar 2008 |
| 112 | Duncan Oil Properties, Inc. | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 113 | Dunigan Operating Company, Inc. | Austin, TX 78755 | Oil & Gas Operator | Oct 2025 |
| 114 | E. T. S. Enterprises, Inc. | Amarillo, TX 79105 | Oil & Gas Operator | Jul 1996 |
| 115 | Eagle Operating | Midland, TX 79707 | Oil & Gas Operator | May 2013 |
| 116 | Eddleman, M. W. | Nichols Hill, OK 73116 | Oil & Gas Operator | Nov 2000 |
| 117 | Edwards & Leach Oil Company | Oklahoma City, OK 73114 | Oil & Gas Operator | Mar 2005 |
| 118 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 119 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 120 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 121 | Eqv Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Oct 2025 |
| 122 | Essman Energy, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2019 |
| 123 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 124 | Etc Field Services LLC | San Antonio, TX 78258 | Oil Operator | Jun 2018 |
| 125 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 126 | Exxcel Production Company | Pampa, TX 79066 | Oil & Gas Operator | Oct 2025 |
| 127 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 128 | Fairway Resources Op III, LLC | Southlake, TX 76092 | Oil & Gas Operator | Oct 2025 |
| 129 | Faulconer Vernon E Inc | Tyler, TX 75711 | Oil & Gas Operator | Jul 2025 |
| 130 | Federer, H. C. | Amarillo, TX 79101 | Oil & Gas Operator | Dec 1993 |
| 131 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Oct 2025 |
| 132 | Flow Production Company | Midland, TX 79708 | Oil & Gas Operator | Mar 2005 |
| 133 | Follett Operating Co. | Darrouzett, TX 79024 | Oil & Gas Operator | Jun 2019 |
| 134 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 135 | Furr, Roy Estate Of | Midland, TX 79702 | Oil & Gas Operator | Jun 2016 |
| 136 | Geodyne Operating Company | Tulsa, OK 74103 | Oil & Gas Operator | Jun 2015 |
| 137 | Gillispie, Inc. | Amarillo, TX 79159 | Gas Operator | Oct 2025 |
| 138 | Glenn Supply Company, Inc. | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2025 |
| 139 | Golden Gas Production Company | Tulsa, OK 74136 | Oil & Gas Operator | May 2025 |
| 140 | Gothic Energy Corporation | Tulsa, OK 74136 | Oil & Gas Operator | Jul 2015 |
| 141 | Granite Operating Company | Houston, TX 77056 | Oil & Gas Operator | Nov 2012 |
| 142 | Grayhawk Operating, Inc. | Oklahoma City, OK 73154 | Oil & Gas Operator | Dec 2006 |
| 143 | Great Plains Operating, LLC. | Grapevine, TX 76051 | Oil & Gas Operator | Aug 2014 |
| 144 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 145 | H & L Exploration Company, LLC | Amarillo, TX 79114 | Oil & Gas Operator | Oct 2025 |
| 146 | H & L Operating Co., L.L.P. | Amarillo, TX 79114 | Oil & Gas Operator | Aug 2022 |
| 147 | H & L Operating Co., LLC | Amarillo, TX 79114 | Oil & Gas Operator | Mar 2021 |
| 148 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 149 | H-S Exploration | Perryton, TX 79070 | Oil & Gas Operator | Oct 2025 |
| 150 | Hadaway Consult And Engineer,LLC | Canadian, TX 79014 | Oil & Gas Operator | Oct 2025 |
| 151 | Hamilton Brothers Oil Co. | Houston, TX 77057 | Oil & Gas Operator | Mar 2015 |
| 152 | Hanley Petroleum Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2017 |
| 153 | Hawkins Oil & Gas Inc | Tulsa, OK 74103 | Oil & Gas Operator | Dec 2016 |
| 154 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Jun 2025 |
| 155 | Highmark Energy Operating, LLC | Dallas, TX 75222 | Oil & Gas Operator | Oct 2025 |
| 156 | Holmes Exploration, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Jun 2015 |
| 157 | Hominy Consulting, LLC | Canadian, TX 79014 | Oil & Gas Operator | Oct 2025 |
| 158 | Horizon Natural Gas Company | Tulsa, OK 74170 | Oil & Gas Operator | Oct 2024 |
| 159 | Horizon Natural Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Jan 2019 |
| 160 | HRB Operating Company, Inc. | Bridgeport, TX 76426 | Oil & Gas Operator | Oct 2025 |
| 161 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 162 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Oct 2025 |
| 163 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 164 | Hy-Tech, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Feb 2017 |
| 165 | Imperial Oil Company | Houston, TX 77073 | Oil & Gas Operator | Oct 2004 |
| 166 | Intercoast Oil And Gas Company | Tulsa, OK 74136 | Oil & Gas Operator | Jun 1997 |
| 167 | J-Brex Company | Amarillo, TX 79101 | Oil & Gas Operator | Oct 2025 |
| 168 | JCB II Enterprises LLC | Perryton, TX 79070 | Oil & Gas Operator | Jun 2023 |
| 169 | Jetta Operating Company Inc | Fort Worth, TX 76102 | Oil & Gas Operator | Oct 2025 |
| 170 | Jil Oil Corp. | San Antonio, TX 78279 | Oil & Gas Operator | Oct 2025 |
| 171 | Jilpetco, Inc. | Fort Worth, TX 76121 | Oil & Gas Operator | Oct 2025 |
| 172 | Jones Energy LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Jun 2025 |
| 173 | Jones Energy, LTD. | Austin, TX 78746 | Oil & Gas Operator | Sep 2013 |
| 174 | K.M.A. Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 175 | Kaiser-Francis Oil Company | Tulsa, OK 74121 | Oil & Gas Operator | Oct 2025 |
| 176 | Karper Oil & Gas Corporation | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 177 | KCS Medallion Resources, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Nov 2018 |
| 178 | KCS Resources, Inc. | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 179 | Kerr-McGee Corporation | Dallas, TX 75380 | Oil & Gas Operator | May 2025 |
| 180 | King Operating Corporation | Fort Worth, TX 76147 | Oil & Gas Operator | Oct 2025 |
| 181 | L & R Energy Corporation | Spearman, TX 79081 | Oil & Gas Operator | Nov 2014 |
| 182 | L And C Leasing, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2019 |
| 183 | Laddex, LTD. | Amarillo, TX 79102 | Oil & Gas Operator | Feb 2025 |
| 184 | Laredo Petroleum, Inc. | Tulsa, OK 74120 | Oil & Gas Operator | Mar 2023 |
| 185 | Large Operating LLC | Stinnett, TX 79083 | Oil & Gas Operator | Oct 2025 |
| 186 | Latigo Petroleum Texas, LP | Houston, TX 77002 | Oil & Gas Operator | Feb 2009 |
| 187 | Latigo Petroleum, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Jun 2025 |
| 188 | Latigo Petroleum, LLC | Pampa, TX 79066 | Oil & Gas Operator | Oct 2025 |
| 189 | Le Norman Operating LLC | Oklahoma City, OK 73142 | Oil & Gas Operator | Nov 2019 |
| 190 | Lease Holders Acquisitions LLC | Yukon, OK 73099 | Gas Operator | Oct 2025 |
| 191 | Lera | Borger, TX 79007 | Oil & Gas Operator | Oct 2025 |
| 192 | Lime Rock Resources II-A, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jun 2025 |
| 193 | Lindenmuth & Associates Inc | Austin, TX 78703 | Oil & Gas Operator | Jun 2025 |
| 194 | Linn Operating, Inc. | Houston, TX 77002 | Oil & Gas Operator | May 2017 |
| 195 | Lomak Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Aug 1998 |
| 196 | Lone Tree Oil & Gas LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Oct 2025 |
| 197 | Makar Production Company | Graham, TX 76450 | Oil & Gas Operator | Oct 2025 |
| 198 | Marsh Operating Company | Dallas, TX 75221 | Oil & Gas Operator | Jun 2025 |
| 199 | Marshall & Winston, Inc. | Midland, TX 79710 | Oil & Gas Operator | Aug 2025 |
| 200 | Martin Oil & Gas | Freer, TX 78357 | Oil & Gas Operator | May 2025 |