| 1 | D&H-S-S Production Co.,Inc | Corpus Chrsti, TX 78409 | Oil & Gas Operator | Aug 2003 |
| 2 | Dalen Resources Oil & Gas Co. | Dallas, TX 75206 | Oil & Gas Operator | Jun 2010 |
| 3 | Dallas Petroleum Group, LLC | Dallas, TX 75379 | Oil & Gas Operator | Apr 2024 |
| 4 | Dalport Oil Corporation | Dallas, TX 75202 | Oil & Gas Operator | Apr 1993 |
| 5 | Davis Petroleum Corp. | Houston, TX 77027 | Oil & Gas Operator | Apr 2024 |
| 6 | Dekalb Energy Company | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 1996 |
| 7 | Dewbre Petroleum Corporation | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2024 |
| 8 | Dinero Oil Corporation | Corpus Chrsti, TX 78460 | Oil & Gas Operator | Nov 1999 |
| 9 | Dirnett, Inc. | Tuleta, TX 78162 | Oil & Gas Operator | Apr 2024 |
| 10 | DKW Energy, Inc. | Sherman Oaks, CA 91403 | Oil & Gas Operator | Apr 2024 |
| 11 | Dogwood Operating Company, Inc. | Houston, TX 77069 | Oil & Gas Operator | Apr 2024 |
| 12 | Dolphin Petroleum | Alice, TX 78333 | Oil & Gas Operator | Jun 2008 |
| 13 | Dolphin Petroleum, LP | Alice, TX 78333 | Oil & Gas Operator | Apr 2024 |
| 14 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 15 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Dec 2014 |
| 16 | Double Play Oil & Gas | Portland, TX 78374 | Oil & Gas Operator | Dec 2001 |
| 17 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Apr 2024 |
| 18 | Dove Creek Energy, Inc. | Fort Worth, TX 76121 | Oil & Gas Operator | Apr 2024 |
| 19 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 20 | Durango Resources Corp | Houston, TX 77043 | Oil & Gas Operator | Apr 2024 |
| 21 | Durst Oil Company | Corpus Chrsti, TX 78477 | Oil & Gas Operator | Sep 2000 |