| 1 | Dakota Resources, Inc | Midland, TX 79707 | Oil & Gas Operator | Jun 2025 |
| 2 | Dakota Resources, Inc. (I) | Midland, TX 79707 | Oil & Gas Operator | Oct 2025 |
| 3 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 4 | Daniels, J.C. Energy | Pampa, TX 79066 | Oil & Gas Operator | Apr 2001 |
| 5 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Oct 2025 |
| 6 | DCP Midstream, LP | Denver, CO 80237 | Oil Operator | Nov 2006 |
| 7 | DCP Operating Co LP | Houston, TX 77042 | Oil & Gas Operator | May 2025 |
| 8 | Delfin Operating, LLC | Dallas, TX 75243 | Oil & Gas Operator | Oct 2025 |
| 9 | Delong, Horace | Pleasanton, TX 78064 | Oil & Gas Operator | Oct 2025 |
| 10 | Desana Development Corporation | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 11 | Devon Energy Corp (Nevada) | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2017 |
| 12 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Oct 2025 |
| 13 | Devon Gas Services, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 2015 |
| 14 | Diamond G Production | FT Stockton, TX 79735 | Oil & Gas Operator | Oct 2025 |
| 15 | Diamondback E&P LLC | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 16 | Dinero Operating Co | Midland, TX 79702 | Oil & Gas Operator | Oct 2025 |
| 17 | Discovery Operating Inc | Midland, TX 79705 | Oil & Gas Operator | Oct 2025 |
| 18 | Dominion Oklahoma Texas E&P, Inc | Richmond, VA 23219 | Oil & Gas Operator | Sep 2018 |
| 19 | Dorado Oil Company | Corpus Chrsti, TX 78403 | Oil & Gas Operator | Oct 2013 |
| 20 | Dorchester Resources LP | Oklahoma City, OK 73154-8879 | Oil & Gas Operator | Aug 2021 |
| 21 | Dorr, John R. | Pecos, TX 79772 | Oil & Gas Operator | Oct 2025 |
| 22 | Double Eagle Operating, LLC | Fort Worth, TX 76113 | Oil & Gas Operator | Oct 2025 |
| 23 | Draco Energy, Inc. | Midland, TX 79701 | Oil & Gas Operator | Oct 2025 |
| 24 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 25 | Drilmor, Inc. | Midland, TX 79701 | Oil & Gas Operator | Feb 1998 |
| 26 | Drum, Delton | Liberty, TX 77575 | Oil & Gas Operator | Jul 2005 |
| 27 | DSR Oil & Gas, Inc. | Monahans, TX 79756 | Oil & Gas Operator | Oct 2025 |
| 28 | Dugan Production Corp | Farmington, NM 87499 | Oil & Gas Operator | Jul 2025 |
| 29 | Durango Resources Corp. | Houston, TX 77043 | Oil & Gas Operator | Oct 2025 |
| 30 | Durham, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jul 2016 |
| 31 | Dyad Petroleum Company | Midland, TX 79710 | Oil & Gas Operator | Sep 2021 |