| 101 | Crimson Energy Company, LC | Fort Worth, TX 76102 | Oil & Gas Operator | Mar 2004 |
| 102 | Crimson Energy PTNRS III, L.L.C. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2023 |
| 103 | Cumming Company, Inc. The | Fort Worth, TX 76116 | Oil & Gas Operator | Oct 2025 |
| 104 | Dale Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 105 | Dartex Energy Corporation | Austin, TX 78746 | Oil & Gas Operator | Oct 2025 |
| 106 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 107 | Dee-Jay Exploration Company | Nichols Hill, OK 73116 | Oil & Gas Operator | Oct 2025 |
| 108 | Delaware Ecco Petroleum Inc. | Rockwall, TX 75087 | Oil & Gas Operator | Jul 2001 |
| 109 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Oct 2025 |
| 110 | Di Energy Inc. | Houston, TX 77067 | Oil & Gas Operator | Jan 2004 |
| 111 | Dixie Drilling Company, Inc. | Sherman, TX 75090 | Oil & Gas Operator | Nov 2011 |
| 112 | Douglas Petroleum Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2010 |
| 113 | DPMP Energy LLC | Prosper, TX 75078 | Oil & Gas Operator | Dec 2023 |
| 114 | Durst Oil Company | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Sep 2000 |
| 115 | Dynamic Petroleum Res., Inc. | Houston, TX 77068 | Oil & Gas Operator | Jul 1994 |
| 116 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Oct 2025 |
| 117 | Dyson Energy Operating, LLC | Bryan, TX 77802 | Oil & Gas Operator | Jun 2018 |
| 118 | E.G. Operating | Dallas, TX 75206 | Oil & Gas Operator | Mar 2008 |
| 119 | E2 Operating LLC | Tulsa, OK 74135 | Oil & Gas Operator | Oct 2025 |
| 120 | Eagle Valley Development LLC | Austin, TX 78738 | Oil & Gas Operator | Oct 2023 |
| 121 | East Texas Production MGT. Inc | Athens, TX 75751 | Oil & Gas Operator | Oct 2025 |
| 122 | Edco Energy, Inc. | Austin, TX 78738 | Oil & Gas Operator | May 2003 |
| 123 | Edwards, Gus Co. | Abilene, TX 79603 | Oil & Gas Operator | Jun 2004 |
| 124 | Emerald Operating Company | Plano, TX 75075 | Oil & Gas Operator | Aug 2025 |
| 125 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 126 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | Mar 2025 |
| 127 | Endeavor Natural Gas, LP | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 128 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 129 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 130 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 131 | Engroup Resources, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 132 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 133 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 134 | Etoco Incorporated | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 135 | Etx Energy, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2022 |
| 136 | Evolution Operating Co., Inc. | Houston, TX 77079 | Oil & Gas Operator | Oct 2025 |
| 137 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Jun 2025 |
| 138 | Express Oil Co. | Hallettsville, TX 77964 | Oil & Gas Operator | Oct 2025 |
| 139 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 140 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 141 | F.I.G. Energy, LLC | Livingston, TX 77399 | Oil & Gas Operator | Oct 2025 |
| 142 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Oct 2025 |
| 143 | Flairtex Resources, Inc. | Houston, TX 77040 | Oil & Gas Operator | Oct 1998 |
| 144 | Forcenergy Onshore Inc. | Houston, TX 77002 | Oil & Gas Operator | Dec 2012 |
| 145 | Ford, Don H. & Assoc. | San Antonio, TX 78217 | Oil & Gas Operator | Oct 2025 |
| 146 | Fuller Petroleum Inc | Midland, TX 79702 | Oil & Gas Operator | Mar 2008 |
| 147 | Future Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 1999 |
| 148 | Garrison LTD. | San Antonio, TX 78257 | Oil & Gas Operator | Oct 2025 |
| 149 | Geosouthern Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 150 | Ginger Petroleum Company, Inc. | La Grange, TX 78945 | Oil & Gas Operator | Oct 2025 |
| 151 | Golden Monet, Inc. | Bryan, TX 77805 | Oil & Gas Operator | Oct 2025 |
| 152 | Goldsmith Operating, LLC | Tyler, TX 75711 | Oil & Gas Operator | Oct 2025 |
| 153 | Goldsmith, J. Paul | Tyler, TX 75711 | Oil & Gas Operator | Feb 1997 |
| 154 | Goldsmith, Neta R. | Tyler, TX 75711 | Oil & Gas Operator | Dec 2009 |
| 155 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 156 | Grand Operating, Inc. | Addison, TX 75001 | Oil & Gas Operator | Dec 2020 |
| 157 | Great West Energy & Expl., Inc. | Addison, TX 75001 | Oil & Gas Operator | Mar 2008 |
| 158 | Great Western Onshore Inc | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 159 | Griffin Petroleum Company | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 160 | Gruy Petroleum Management Co. | Irving, TX 75014 | Oil & Gas Operator | Nov 2014 |
| 161 | Gsi Oil & Gas, Inc. | Bryan, TX 77806 | Oil & Gas Operator | Oct 2025 |
| 162 | Guest Petroleum Incorporated | Edmond, OK 73013 | Oil & Gas Operator | Jul 2025 |
| 163 | Gulf Tide Oil Company, The | Houston, TX 77008 | Oil & Gas Operator | Jun 1999 |
| 164 | H H Exploration, Inc. | Incline VLLG, NV 89451 | Gas Operator | Feb 2018 |
| 165 | Halcon Operating Co., Inc. | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 166 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 167 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Oct 2025 |
| 168 | Harper Oil And Gas, LLC | Pratt, KS 67124 | Oil & Gas Operator | Jun 2025 |
| 169 | Harvey, Mike W. Oil & Gas | Corpus Chrsti, TX 78408 | Oil & Gas Operator | Aug 2003 |
| 170 | Hawkwood Energy Operating, LLC | Houston, TX 77224 | Oil & Gas Operator | Apr 2022 |
| 171 | Hawn Brothers | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2003 |
| 172 | Hep Oil Company LTD | Gainesville, TX 76240 | Oil & Gas Operator | Mar 2012 |
| 173 | Hep Oil GP, LLC | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 174 | Hibbard Energy, LP | Whitehouse, TX 75791 | Oil & Gas Operator | Oct 2025 |
| 175 | HK Energy Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2023 |
| 176 | Hoc Operating Co., Inc. | Houston, TX 77056 | Oil & Gas Operator | Nov 1999 |
| 177 | Holley Oil Company, LLC | Chappell Hill, TX 77426 | Oil & Gas Operator | Oct 2025 |
| 178 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Oct 2025 |
| 179 | Houston Resources Corp. | Houston, TX 77002 | Oil & Gas Operator | Apr 2003 |
| 180 | Howell Petroleum Corporation | Houston, TX 77251 | Oil & Gas Operator | Oct 2015 |
| 181 | HPC Operating, Inc. | Dallas, TX 75379 | Oil & Gas Operator | Mar 2008 |
| 182 | Hrubetz Oil Co. | Dallas, TX 75225 | Oil Operator | Sep 1986 |
| 183 | Huber Energy L.P. | Houston, TX 77079 | Oil & Gas Operator | Feb 2007 |
| 184 | Huber Energy Panhandle LP | Houston, TX 77079 | Oil & Gas Operator | Oct 2005 |
| 185 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Oct 2025 |
| 186 | Hunter Petroleum Inc. | Alice, TX 78333 | Oil & Gas Operator | May 2014 |
| 187 | Idgas, Inc. | Austin, TX 78746 | Oil & Gas Operator | Oct 1995 |
| 188 | Imperial Oil Company | Houston, TX 77073 | Oil & Gas Operator | Oct 2004 |
| 189 | Impetro Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Nov 2020 |
| 190 | Indexgeo & Associates, Inc. | Houston, TX 77002 | Oil & Gas Operator | Apr 2009 |
| 191 | Indian Exploration, Inc. | Lafayette, LA 70505 | Oil & Gas Operator | Oct 2025 |
| 192 | Ineos USA Oil & Gas LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 193 | Inexco Oil Company | Houston, TX 77210 | Oil & Gas Operator | Mar 2013 |
| 194 | Itech Oil Company | Cypress, TX 77429 | Oil & Gas Operator | Aug 2007 |
| 195 | J C Petroleum Inc | Chickasha, OK 73023-1433 | Oil & Gas Operator | Dec 2013 |
| 196 | Jordan Engineering, Inc. | Abilene, TX 79601 | Oil & Gas Operator | Oct 2025 |
| 197 | Juneau Energy, LLC | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 198 | K.M.A. Operating, Inc. | Graham, TX 76450 | Oil & Gas Operator | Aug 2003 |
| 199 | Kachina Oil & Gas Inc. | Austin, TX 78766 | Oil & Gas Operator | Jul 2002 |
| 200 | Kenworthy Operating Company | Tulsa, OK 74132 | Oil & Gas Operator | May 2009 |