| 1 | D & D Enterprises | Post, TX 79356 | Oil & Gas Operator | Oct 2025 |
| 2 | D90 Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 3 | Dakota Resources, Inc. (I) | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 4 | Davis & Carr Energy Co. | Midland, TX 79702 | Oil & Gas Operator | Jun 1994 |
| 5 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 6 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 7 | Diamond M Oil Co., Inc. | Monahans, TX 79756 | Oil & Gas Operator | Oct 2025 |
| 8 | Diamondback E&P LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 9 | Diamondback Resources LLC | Midland, TX 79705 | Oil & Gas Operator | May 2018 |
| 10 | Diler Development Inc. | Garland, TX 75043 | Oil & Gas Operator | Oct 2025 |
| 11 | Dinero Operating Co | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 12 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Oct 2025 |
| 13 | Down-Hole Pump Service Co., Inc. | Fort Worth, TX 76109 | Oil & Gas Operator | Oct 2025 |
| 14 | Dreher, George R. | Midland, TX 79702 | Oil & Gas Operator | Jan 2018 |
| 15 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 16 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 17 | Duke, M. L. | Snyder, TX 79549 | Oil & Gas Operator | Mar 2008 |
| 18 | Dune Oil And Gas, Inc. | Odessa, TX 79768 | Oil & Gas Operator | Aug 2006 |
| 19 | Dunigan Operating Company, Inc. | Austin, TX 78755 | Oil & Gas Operator | Oct 2025 |
| 20 | Dunigan Petroleum, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Aug 2003 |
| 21 | Durham, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2016 |
| 22 | Dym Energy, Inc. | Celina, TX 75009 | Oil & Gas Operator | Apr 2018 |