| 101 | Culoco, Inc. | Dallas, TX 75374 | Oil & Gas Operator | Nov 2024 |
| 102 | Cxy Energy, Inc. | Dallas, TX 75251 | Oil & Gas Operator | Nov 2000 |
| 103 | Cypress Production, Inc. | Azle, TX 76020 | Oil & Gas Operator | Oct 2025 |
| 104 | Damson Oil Corporation | Houston, TX 77210 | Oil & Gas Operator | Mar 2005 |
| 105 | Daniel Oil Company | | Oil & Gas Operator | Jan 1983 |
| 106 | Davis Oil Company | Denver, CO 80202 | Oil & Gas Operator | Jun 1988 |
| 107 | Dawson Exploration, Inc. | | Oil & Gas Operator | Jun 1986 |
| 108 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 109 | DBL DRLG.&Prod. Services, Inc. | | Oil & Gas Operator | Jul 1997 |
| 110 | Dean Enterprises, Inc. | | Oil & Gas Operator | Jun 2019 |
| 111 | Deck Oil Company | Tulsa, OK 74101 | Oil & Gas Operator | Jun 2020 |
| 112 | Delta Energy Resources, Inc. | | Oil & Gas Operator | Jun 1990 |
| 113 | Deltaus Corporation | | Oil & Gas Operator | Oct 1985 |
| 114 | Denali Oil & Gas Management, LLC | Houston, TX 77060 | Oil & Gas Operator | Dec 2012 |
| 115 | Denovo Oil & Gas, Inc. | Houston, TX 77210 | Oil & Gas Operator | May 1995 |
| 116 | Devon Energy Operating Co., L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2009 |
| 117 | Di Energy Inc. | Houston, TX 77067 | Oil & Gas Operator | Jan 2004 |
| 118 | Diamond D Operating | | Oil & Gas Operator | Apr 1995 |
| 119 | Dimension Energy Co., L.L.C. | | Oil & Gas Operator | Dec 2024 |
| 120 | Discovery Energy, LLC | | Oil Operator | Jan 2007 |
| 121 | Discovery Operating, LLC | | Oil & Gas Operator | Oct 2023 |
| 122 | Dome De Sel LLC | | Oil & Gas Operator | Nov 2024 |
| 123 | Dome Petroleum Corp | Denver, CO 80202 | Oil & Gas Operator | Dec 2016 |
| 124 | Dow Intrastate Gas Company | | Oil Operator | Dec 2023 |
| 125 | Duer Wagner & Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1998 |
| 126 | Duncan Oil Inc | Denver, CO 80210 | Oil & Gas Operator | Jun 2016 |
| 127 | Dune Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Jun 2016 |
| 128 | Dunn Exploration Company, LLC | | Oil & Gas Operator | Jan 2025 |
| 129 | Dynaco, Incorporated | | Oil & Gas Operator | Dec 1980 |
| 130 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 131 | Eastern Oil Corporation | Houston, TX 77070 | Oil & Gas Operator | Oct 2025 |
| 132 | Eclipse Services, Inc. * | La Grange, TX 78945 | Oil & Gas Operator | Jul 2003 |
| 133 | Edwin L. Cox | | Oil & Gas Operator | May 1986 |
| 134 | Edwin L. Cox & Berry R. Cox | | Oil & Gas Operator | Jun 1986 |
| 135 | Elysium Energy, L.L.C. | Denver, CO 80202 | Oil & Gas Operator | Jun 2019 |
| 136 | Elysium Jennings, LLC | | Oil & Gas Operator | Dec 2024 |
| 137 | Empire Land Corporation | New Orleans, LA 70130 | Oil & Gas Operator | Nov 2014 |
| 138 | Energen Resources Maq Inc | Birmingham, AL 35203 | Oil & Gas Operator | Sep 2000 |
| 139 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2024 |
| 140 | Energy Investments Inc | | Oil & Gas Operator | Aug 2025 |
| 141 | Energy Properties Inc. | | Oil & Gas Operator | Dec 2023 |
| 142 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 143 | Entex, Inc. | | Oil & Gas Operator | Dec 1984 |
| 144 | Equinox Oil Company | Plainville, KS 67663 | Oil & Gas Operator | Dec 2019 |
| 145 | Equipment, Inc. | | Oil & Gas Operator | Mar 1983 |
| 146 | Ethyl Properties Inc. | | Oil & Gas Operator | Aug 1989 |
| 147 | Etoco, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 148 | Exchange Oil & Gas Corporation | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1987 |
| 149 | Exodus Energy, Inc. | Huntington Beach, CA 92615 | Oil & Gas Operator | Jul 2018 |
| 150 | Expert Oil & Gas, L.L.C. | | Oil & Gas Operator | Nov 2024 |
| 151 | Ferguson Oil Company Inc | | Oil & Gas Operator | Apr 1994 |
| 152 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 153 | Finaly Resources LLC | Sunset Beach, CA 90742 | Oil & Gas Operator | Oct 2025 |
| 154 | First Energy Corporation | | Oil & Gas Operator | Jun 1993 |
| 155 | Five-Jab, Inc. | Tomball, TX 77377 | Oil & Gas Operator | Oct 2025 |
| 156 | Flash Gas & Oil Northeast, Inc | | Oil & Gas Operator | May 2007 |
| 157 | Florida Exploration Co | Aurora, CO 80014 | Oil & Gas Operator | Sep 1989 |
| 158 | Florida Gas Transmission Co. | | Oil Operator | Dec 2007 |
| 159 | FMP Operating Co., LTD. PTN. | | Oil & Gas Operator | Mar 1990 |
| 160 | Forest Oil Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 161 | Forexco, Inc. | Greensboro, NC 27438 | Oil & Gas Operator | Dec 2020 |
| 162 | Forman Petroleum Corporation | | Oil & Gas Operator | Aug 2001 |
| 163 | Formentera Operations LLC | Austin, TX 78701 | Oil & Gas Operator | Oct 2025 |
| 164 | Fort Apache Energy, Inc. | Boerne, TX 78015 | Oil & Gas Operator | Oct 2025 |
| 165 | Forza Operating, LLC | The Woodlands, TX 77380 | Oil & Gas Operator | Oct 2025 |
| 166 | Frank B. Aumiller | | Oil Operator | Jun 1991 |
| 167 | Frank C. VInson | | Oil & Gas Operator | May 1995 |
| 168 | Future Oil & Gas, Inc. | | Oil & Gas Operator | Mar 2010 |
| 169 | G & P Exploration, Inc. | | Oil Operator | Aug 1987 |
| 170 | Gaither Petroleum Corporation | Katy, TX 77493 | Oil & Gas Operator | Oct 2025 |
| 171 | Gap Energy, Inc. | | Oil & Gas Operator | Oct 1995 |
| 172 | Geb Operating, LLC | | Oil & Gas Operator | Jan 2025 |
| 173 | Ged Oil Corporation | | Oil & Gas Operator | Aug 2012 |
| 174 | General American Oil Co Of TX | | Oil & Gas Operator | Jun 1983 |
| 175 | General Atlantic Energy Corp. | | Oil & Gas Operator | Nov 1988 |
| 176 | General Oil Company, Inc. | Wichita, KS 67213 | Oil & Gas Operator | Oct 2025 |
| 177 | Germany Operating Company | Houston, TX 77090 | Oil & Gas Operator | Sep 2011 |
| 178 | Getty Oil Company | Hays, KS 67601 | Oil & Gas Operator | Mar 2015 |
| 179 | Getty Reserve Oil, Inc. | White Plains, NY 10650 | Oil & Gas Operator | Mar 2005 |
| 180 | Glasscock Drilling, Inc. | | Oil & Gas Operator | Dec 1977 |
| 181 | Goldco Operating LLC | Shreveport, LA 71101 | Oil & Gas Operator | Aug 2020 |
| 182 | Goldking Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Jun 2007 |
| 183 | Goldking Prod. Co. | Houston, TX 77002 | Oil & Gas Operator | Apr 1998 |
| 184 | Goldrus Producing Company | Houston, TX 77064 | Oil & Gas Operator | Aug 2009 |
| 185 | Goldsberry Operating Co., Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Aug 2020 |
| 186 | Goodrich Oil Company | Shreveport, LA 71101 | Oil & Gas Operator | Nov 2001 |
| 187 | Goodrich Petroleum Company | Houston, TX 77002 | Oil & Gas Operator | Feb 2022 |
| 188 | Goodrich Petroleum Corporation | | Oil & Gas Operator | Sep 1996 |
| 189 | Gordy Oil Company | Houston, TX 77007 | Oil & Gas Operator | Oct 2025 |
| 190 | Grace Petroleum Corp. | Tulsa, OK 74103 | Oil & Gas Operator | Oct 1997 |
| 191 | Graham Exploration, LTD. | | Oil & Gas Operator | Oct 1993 |
| 192 | Graham Royalty LTD | Covington, LA 70434 | Oil & Gas Operator | Jul 2007 |
| 193 | Great River Oil & Gas Corp. | | Oil & Gas Operator | Sep 1998 |
| 194 | Great Scott, Inc. | | Oil & Gas Operator | Oct 1993 |
| 195 | Great Southern Oil &Gas Co Inc | | Oil & Gas Operator | Dec 2004 |
| 196 | Gulf Oil Corp. | Denver, CO 80201-0599 | Oil & Gas Operator | Dec 2014 |
| 197 | Gulf South Pipeline Company, LLC | | Oil & Gas Operator | Jan 2025 |
| 198 | Gulf South Pipeline Company, LP | Houston, TX 77001 | Oil & Gas Operator | Dec 2020 |
| 199 | Hal Oil & Gas Co., Inc. | | Oil & Gas Operator | Apr 1993 |
| 200 | Hawthorne Oil And Gas Corp. | Houston, TX 77227 | Oil & Gas Operator | Sep 1993 |