| 101 | Clayton Williams Energy, Inc. | Houston, TX 77070 | Oil & Gas Operator | Apr 2017 |
| 102 | Cleveland Production Company | Summit, MS 39666 | Oil & Gas Operator | Jul 1999 |
| 103 | Clinch Drilling Company | | Oil & Gas Operator | Jan 2000 |
| 104 | CMW Oil Company | | Oil & Gas Operator | Dec 1976 |
| 105 | Cobra Oil & Gas Corporation | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2025 |
| 106 | Cody Operating, Inc. | | Oil & Gas Operator | Aug 2025 |
| 107 | Coho Resources Inc. | Dallas, TX 75240 | Oil & Gas Operator | Jul 2002 |
| 108 | Collins Associates Inc | | Oil & Gas Operator | Mar 1987 |
| 109 | Colt Energy Inc | Iola, KS 66749 | Oil & Gas Operator | Jun 2025 |
| 110 | Columbia Petroleum LLC | Oyster Bay, NY 11771 | Oil & Gas Operator | Feb 2025 |
| 111 | Comstock Oil & Gas, LP | Frisco, TX 75034 | Oil & Gas Operator | Aug 2019 |
| 112 | Conquest Exploration Co. | | Oil & Gas Operator | Mar 1992 |
| 113 | Consolidated Engy Reserve Inc | | Oil & Gas Operator | Jul 1991 |
| 114 | Continental Oil Co. | Durango, CO 81301 | Oil & Gas Operator | Dec 1983 |
| 115 | Cornwell Well Service, Inc. | | Oil & Gas Operator | Feb 2010 |
| 116 | Cornwell, G. G. | | Oil & Gas Operator | Sep 2009 |
| 117 | Craft Petroleum Company, Inc. Et Al | | Oil & Gas Operator | Mar 1997 |
| 118 | Crain & Dore' | | Oil & Gas Operator | May 1986 |
| 119 | Crook-Woodlin Expl.,Inc. | | Oil Operator | Feb 1988 |
| 120 | Crystal Oil Company | Shreveport, LA 71120 | Oil & Gas Operator | Jul 1995 |
| 121 | CWF Associates, LTD. | | Oil & Gas Operator | Apr 1988 |
| 122 | D & D Exploration Co. Et Al | | Oil Operator | Feb 1988 |
| 123 | D. A. Biglane Operating Co Et Al | | Oil Operator | Feb 2004 |
| 124 | Dale Exploration Co. | | Oil & Gas Operator | May 2004 |
| 125 | Dallas Production Company LLC | Dallas, TX 75206 | Oil & Gas Operator | Nov 2025 |
| 126 | Dapsco, Inc. | | Oil & Gas Operator | Dec 1976 |
| 127 | David New Operating Co. Inc. | | Oil & Gas Operator | Feb 1999 |
| 128 | David New Operating-Belle Exp | | Oil Operator | Mar 1990 |
| 129 | Day Dreams Resources, LLC | | Oil & Gas Operator | Aug 2025 |
| 130 | Deeprock Disposal Services, LLC | | Oil & Gas Operator | Sep 1991 |
| 131 | Deepwell Co | | Oil Operator | Jul 1989 |
| 132 | Del Oil & Gas Corp | | Oil Operator | Jul 1981 |
| 133 | Delphi Oil Inc. | | Oil & Gas Operator | Sep 2025 |
| 134 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 135 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Nov 2025 |
| 136 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 137 | Diamond Onshore Production, L. L. C. | | Oil & Gas Operator | Sep 2005 |
| 138 | Diamondhead Oil Co., LLC | | Oil & Gas Operator | Aug 2025 |
| 139 | Dixie Operating Company | Spring, TX 77379 | Oil & Gas Operator | Dec 2002 |
| 140 | Domestic Oil Producers | | Oil Operator | Oct 1980 |
| 141 | Domestic Oil Production | | Oil & Gas Operator | Oct 1989 |
| 142 | Double J Operating Company, Inc. | San Antonio, TX 78205 | Oil Operator | Jan 2008 |
| 143 | Duer Wagner & Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1998 |
| 144 | Duncan-Taylor & Schumacher | | Oil & Gas Operator | Nov 1987 |
| 145 | Durango Operating LLC | Madison, MS 39110 | Oil & Gas Operator | Sep 2025 |
| 146 | E. B. Germany & Sons, LLC | | Oil & Gas Operator | Dec 2011 |
| 147 | E2 Operating LLC | Tulsa, OK 74135 | Oil & Gas Operator | Nov 2025 |
| 148 | Eagle Oil & Gas, LLC (Dba Eagle Oil & Gas Co.) | | Oil & Gas Operator | Dec 2021 |
| 149 | Easom, Dave Production Co Inc | | Oil & Gas Operator | Nov 1998 |
| 150 | East Bay Petroleum | | Oil & Gas Operator | Dec 1987 |
| 151 | Echols & Assoc. | | Oil Operator | Apr 1986 |
| 152 | Eclipse Petroleum | | Oil & Gas Operator | Aug 1991 |
| 153 | Edwards Producing Co.,Inc. | | Oil Operator | Jun 1987 |
| 154 | El Toro Oil Co. & Flagg Resc. | | Oil & Gas Operator | May 1993 |
| 155 | El Toro Production Co Inc | | Oil & Gas Operator | Jan 2016 |
| 156 | Eland Energy Inc | Dallas, TX 75248 | Oil & Gas Operator | Sep 2025 |
| 157 | Elite Group LLC | | Oil & Gas Operator | Aug 2025 |
| 158 | Emerge Operating, LLC | | Oil & Gas Operator | Jul 2025 |
| 159 | Energen Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2021 |
| 160 | Energy Dev Corp | | Oil & Gas Operator | Mar 1998 |
| 161 | Energy Exploration Co | | Oil & Gas Operator | Feb 1991 |
| 162 | Energy Production Service Inc | | Oil Operator | Mar 1986 |
| 163 | Energy Reserves Group, Inc. | Wichita, KS 67202 | Oil & Gas Operator | May 2002 |
| 164 | Enex Rexources Corp. | | Oil & Gas Operator | Jul 1981 |
| 165 | Enserch Exploration | | Oil & Gas Operator | Oct 1996 |
| 166 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Nov 2025 |
| 167 | Eor LLC | | Oil & Gas Operator | Nov 2013 |
| 168 | EP Operating Co. | Dallas, TX 75201 | Oil & Gas Operator | Jan 1993 |
| 169 | Epstein Jr Oper Co | | Oil & Gas Operator | Mar 1991 |
| 170 | Escambia Operating Co., LLC | Gulfport, MS 39501 | Oil & Gas Operator | Aug 2025 |
| 171 | Estate Of William G. Helis | | Oil & Gas Operator | May 1994 |
| 172 | Ethyl Properties Inc | | Oil & Gas Operator | Aug 1989 |
| 173 | Euromin Canada, Inc. | | Oil & Gas Operator | Mar 1987 |
| 174 | Exchange Exploration & Production Co. | Dallas, TX 75219 | Oil & Gas Operator | Aug 2025 |
| 175 | Exco Resources Inc | Dallas, TX 75251 | Oil & Gas Operator | Aug 2025 |
| 176 | Exxon Corporation -La | | Oil & Gas Operator | Sep 1989 |
| 177 | Exxon Corporation -TX | | Oil & Gas Operator | Jan 1982 |
| 178 | F & H Production Service | | Oil & Gas Operator | Apr 1987 |
| 179 | FBN Operating Co | | Oil Operator | Nov 1986 |
| 180 | FDL Operating, LLC | Judson, TX 75660 | Oil & Gas Operator | Nov 2025 |
| 181 | Fi-Ro Corporation | Natchez, MS BADADDR | Oil & Gas Operator | Nov 2001 |
| 182 | Fina Oil And Chemical Company | Dallas, TX 75221 | Oil & Gas Operator | May 2019 |
| 183 | Finley Resources Inc | Fort Worth, TX 76113 | Oil & Gas Operator | Nov 2025 |
| 184 | First Energy Corporation | | Oil & Gas Operator | Jun 1993 |
| 185 | Flare Inc | | Oil & Gas Operator | Jul 1995 |
| 186 | Fletcher Operating Co. | | Oil & Gas Operator | May 1989 |
| 187 | Fletcher Petroleum Corp. | Fairhope, AL 36533 | Oil & Gas Operator | Sep 2025 |
| 188 | Flora Resources LLC | | Oil Operator | Aug 2025 |
| 189 | Florabama Assoc Inc | | Oil & Gas Operator | Jan 2000 |
| 190 | Florida Exploration Co | Aurora, CO 80014 | Oil & Gas Operator | Sep 1989 |
| 191 | Formentera Operations LLC | Austin, TX 78701 | Oil & Gas Operator | Nov 2025 |
| 192 | Fortenbery Operating Co Inc | | Oil & Gas Operator | May 1993 |
| 193 | Fortenbery Wade | | Oil & Gas Operator | May 1980 |
| 194 | Fortson Oil | | Oil & Gas Operator | Jan 1998 |
| 195 | Four Rivers Exploration, Inc. | | Oil & Gas Operator | Sep 2002 |
| 196 | Francis Oil & Gas, LLC | | Oil & Gas Operator | Jan 2011 |
| 197 | Francis, Joseph | | Oil Operator | Dec 1982 |
| 198 | Franklin Properties LLC | | Oil & Gas Operator | Aug 1998 |
| 199 | Franks Petroleum Inc. | | Oil & Gas Operator | Nov 1994 |
| 200 | Frio Exploration, L.L.C. | | Gas Operator | Aug 2000 |