| 1 | Dacott Oil & Gas, LLC | Pampa, TX 79065 | Oil & Gas Operator | Sep 2011 |
| 2 | Dakota Resources, Inc | Midland, TX 79707 | Oil & Gas Operator | Feb 2026 |
| 3 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 4 | Davis & Carr Energy Co. | Midland, TX 79702 | Oil & Gas Operator | Jun 1994 |
| 5 | Day Resources, Inc. | Midland, TX 79707 | Oil & Gas Operator | Aug 1994 |
| 6 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | Nov 2025 |
| 7 | De IV Operating, LLC | Midland, TX 79701 | Oil & Gas Operator | Apr 2025 |
| 8 | De Operating LLC | Austin, TX 78701 | Oil & Gas Operator | Apr 2017 |
| 9 | De3 Operating LLC | Irving, TX 75038 | Oil & Gas Operator | Jun 2021 |
| 10 | Dean Energy, Inc. | Midland, TX 79702 | Oil & Gas Operator | Nov 2019 |
| 11 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | May 2026 |
| 12 | Desert Production, Inc. | Midland, TX 79702 | Oil & Gas Operator | May 2026 |
| 13 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 14 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | May 2026 |
| 15 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 16 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 17 | Diamond S Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | May 2026 |
| 18 | Diamondback E&P LLC | Midland, TX 79701 | Oil & Gas Operator | May 2026 |
| 19 | Discovery Operating Inc | Midland, TX 79705 | Oil & Gas Operator | May 2026 |
| 20 | DNR Oil And Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Feb 2026 |
| 21 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 22 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 23 | Double Eagle Operating, LLC | Fort Worth, TX 76107 | Oil & Gas Operator | May 2026 |
| 24 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | May 2026 |
| 25 | Double T Energy LLC | Lenorah, TX 79749 | Oil Operator | May 2026 |
| 26 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 27 | Durham, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2016 |
| 28 | Dynamic Production, Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | May 2026 |