| 101 | Daniels Corporation, The | Seabrook, TX 77586 | Oil & Gas Operator | Oct 2025 |
| 102 | Davis Bros. Oil Producers, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Apr 2020 |
| 103 | Davis Petroleum Corp. | Houston, TX 77027 | Oil & Gas Operator | Oct 2025 |
| 104 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 105 | Delaware Davis Petroleum Corp. | Houston, TX 77056 | Oil & Gas Operator | Jan 2000 |
| 106 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Oct 2025 |
| 107 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 108 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Oct 2025 |
| 109 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 110 | Diamond Operating, LLC | Wichita Falls, TX 76308 | Oil & Gas Operator | Aug 2010 |
| 111 | Diamond S Masada LLC | Magnolia, TX 77354 | Oil & Gas Operator | Oct 2025 |
| 112 | Dogwood Operating Company, Inc. | Houston, TX 77069 | Oil & Gas Operator | Oct 2025 |
| 113 | Dominion Exploration & Production Inc | Houston, TX 77060 | Oil & Gas Operator | Apr 2015 |
| 114 | Douglas Petroleum Inc. | Spring, TX 77379 | Oil & Gas Operator | Nov 2010 |
| 115 | Duncan Energy Company | Denver, CO 80202 | Oil & Gas Operator | Mar 2008 |
| 116 | Eastern Oil Corporation | Houston, TX 77070 | Oil & Gas Operator | Oct 2025 |
| 117 | Ecc Energy Corporation | Dewey, OK 74029 | Oil & Gas Operator | Feb 2020 |
| 118 | Eclipse Petroleum Corporation | La Grange, TX 78945 | Oil & Gas Operator | Aug 2003 |
| 119 | Eclipse Services, Inc. * | La Grange, TX 78945 | Oil & Gas Operator | Jul 2003 |
| 120 | Eex E&P Company, L.P. | Houston, TX 77060 | Oil & Gas Operator | Jul 2003 |
| 121 | Eex Operating, L.P. | Houston, TX 77060 | Oil & Gas Operator | Jul 2003 |
| 122 | El Tres Exploration | Houston, TX 77098 | Oil & Gas Operator | Mar 2008 |
| 123 | Elliott Oil & Gas Company | The Woodlands, TX 77380 | Oil & Gas Operator | Sep 2006 |
| 124 | Elliott Oil & Gas Operating Co. | Magnolia, TX 77354 | Oil & Gas Operator | Oct 2025 |
| 125 | Elliott Oil Company, L.P. | Magnolia, TX 77354 | Oil & Gas Operator | Oct 2025 |
| 126 | Ellsworth, H. P. O&G Properties | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Oct 2025 |
| 127 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 128 | Energy Reserves Group LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2018 |
| 129 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 130 | Energy Transfer Crude Marketing LLC | Dallas, TX 75225 | Oil Operator | May 2025 |
| 131 | Engroup Resources, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 132 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 133 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 134 | EOG Resources, Inc. | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 135 | Erg Operating Company Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 2006 |
| 136 | Erg Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2015 |
| 137 | Erskine Energy, LLC | H SPG NTL PK, AR 71909 | Oil & Gas Operator | Oct 2025 |
| 138 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Jun 2025 |
| 139 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 140 | Etoco Incorporated | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 141 | Etoco, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 142 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
| 143 | Exxon Mobil Corporation | Spring, TX 77389 | Oil & Gas Operator | Oct 2025 |
| 144 | Exxonmobil Oil Corp | Houston, TX 77210 | Oil & Gas Operator | Jul 2025 |
| 145 | Fairways Exploration & Production, LLC | Houston, TX 77057 | Oil & Gas Operator | Aug 2025 |
| 146 | Falcon Bay Operations, LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2007 |
| 147 | Famcor Oil, Inc. | Scottsdale, AZ 85260 | Oil & Gas Operator | Sep 2020 |
| 148 | Fieldwood Onshore LLC | Houston, TX 77098 | Oil & Gas Operator | Oct 2025 |
| 149 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 150 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Oct 2025 |
| 151 | Flow Energy Inc. | Bellaire, TX 77401 | Oil & Gas Operator | Sep 1996 |
| 152 | Force 4 Energy Resources, Inc. | Austin, TX 78733 | Oil & Gas Operator | Aug 2005 |
| 153 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 154 | Forney Oil Corporation | Houston, TX 77056 | Oil & Gas Operator | Jan 1998 |
| 155 | Fort Apache Energy, Inc. | Boerne, TX 78015 | Oil & Gas Operator | Oct 2025 |
| 156 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 157 | Fredonia Resources Inc. | Longview, TX 75606 | Oil & Gas Operator | Aug 2003 |
| 158 | French Production Incorporated | Houston, TX 77086 | Oil & Gas Operator | Dec 1997 |
| 159 | Gaither Petroleum Corporation | Katy, TX 77493 | Oil & Gas Operator | Oct 2025 |
| 160 | Galveston Bay Energy, LLC | Spring, TX 77386 | Oil & Gas Operator | Jul 2017 |
| 161 | Galveston Bay Operating Co LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 162 | Gary Oil & Gas | Deer Park, TX 77536 | Oil & Gas Operator | Oct 2025 |
| 163 | Gcows Operating LLC | Montgomery, TX 77356 | Oil Operator | Oct 2025 |
| 164 | Genesis Producing Company | Houston, TX 77024 | Oil & Gas Operator | Oct 2007 |
| 165 | Goldking Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 166 | Goldston Oil Corporation | Houston, TX 77257 | Oil & Gas Operator | Oct 2025 |
| 167 | Good Ol'Boys Oil Company | Houston, TX 77057 | Oil & Gas Operator | Oct 2025 |
| 168 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 169 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 170 | Grand Operating, Inc. | Addison, TX 75001 | Oil & Gas Operator | Dec 2020 |
| 171 | Great Texas Crude Inc. | Fredericksbrg, TX 78624 | Oil & Gas Operator | Oct 2025 |
| 172 | Green Exploration Company | Austin, TX 78711 | Oil & Gas Operator | Oct 2025 |
| 173 | Grimes Energy Company | Abilene, TX 79604 | Oil & Gas Operator | Mar 2005 |
| 174 | Gulf Resource Recovery Corp. | Dickinson, TX 77539 | Oil & Gas Operator | Oct 2025 |
| 175 | Gulf Shore Petro. Oper. Co., Inc | Woodland HLS, CA 91367 | Oil & Gas Operator | Apr 1998 |
| 176 | Gulf States Production Company | Houston, TX 77027 | Oil & Gas Operator | Aug 1997 |
| 177 | H.E.R. Operating, LLC | Silsbee, TX 77656 | Oil & Gas Operator | Oct 2025 |
| 178 | Hallwood Petroleum, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2025 |
| 179 | Hamman Oil & Refining Company | Houston, TX 77098 | Oil & Gas Operator | Oct 2025 |
| 180 | Hanson Minerals Co. | Houston, TX 77042 | Oil & Gas Operator | Oct 1993 |
| 181 | Hanson Production Company | Cuero, TX 77954 | Oil & Gas Operator | Jul 2009 |
| 182 | Harrison Interests, LTD. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 183 | Harrison, Dan J III&Bruce F Est | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 184 | Harrison, Dan J. III&Bruce F. | Houston, TX 77002 | Oil & Gas Operator | Mar 2008 |
| 185 | Headington Oil Company | Dallas, TX 75231 | Oil & Gas Operator | Dec 2016 |
| 186 | Hec Petroleum, Inc | Midland, TX 79705 | Oil & Gas Operator | Mar 2006 |
| 187 | Hemco Development, LLC | Dallas, TX 75201 | Oil & Gas Operator | Nov 2020 |
| 188 | Hemco Production, L. L. C. | Dallas, TX 75201 | Oil & Gas Operator | Apr 2016 |
| 189 | Henderson, Peter Oil Co. | San Angelo, TX 76906 | Oil & Gas Operator | Feb 2020 |
| 190 | Hilcorp Energy Company | Houston, TX 77208 | Oil & Gas Operator | Oct 2025 |
| 191 | Hitex Resources, LP | Houston, TX 77265 | Oil & Gas Operator | Oct 2025 |
| 192 | Home Petroleum Corp | Victoria, TX 77902 | Oil & Gas Operator | Oct 2025 |
| 193 | Houston Energy Operating, L.P. | Houston, TX 77002 | Oil & Gas Operator | Jul 2020 |
| 194 | Houston Gulf Energy Corporation | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 195 | Houston Oil & Minerals Corp. | Houston, TX 77002 | Oil & Gas Operator | Aug 1996 |
| 196 | Houston Oil Prod Enterprises,Inc | Houston, TX 77006 | Oil & Gas Operator | Oct 2025 |
| 197 | Howard Exploration, Inc. | Houston, TX 77069 | Oil & Gas Operator | Oct 2025 |
| 198 | HS Resources, Inc. | Denver, CO 80202 | Oil & Gas Operator | Dec 2005 |
| 199 | Hunt Oil Company | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 200 | Hurley Petroleum Corporation | Baton Rouge, LA 70821 | Oil & Gas Operator | Feb 2000 |