| 1 | D&S Oil & Gas Operators, Inc. | | Oil & Gas Operator | Dec 2020 |
| 2 | D. B. McConnell | | Oil & Gas Operator | Oct 1991 |
| 3 | D. B. McConnell Et Al | | Oil & Gas Operator | Nov 1993 |
| 4 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 5 | David Crow | | Oil & Gas Operator | Nov 1985 |
| 6 | David Lynn Chiles | | Oil & Gas Operator | Aug 2020 |
| 7 | DCP Midstream, LLC | | Oil Operator | Jun 2016 |
| 8 | DDC & T Operating Company, Inc | | Oil & Gas Operator | Jul 2005 |
| 9 | Dean Petroleum | | Oil & Gas Operator | Jun 2000 |
| 10 | Deep South Production | | Oil Operator | Dec 2023 |
| 11 | Delta Petroleum Inc | Houston, TX 77269-1007 | Oil & Gas Operator | May 2009 |
| 12 | Demiran Production, Inc. | | Oil Operator | Mar 2008 |
| 13 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Feb 2026 |
| 14 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 15 | Devon SFS Operating Inc | Oklahoma City, OK 73102 | Oil & Gas Operator | Mar 2008 |
| 16 | Dewey Williams | | Oil Operator | Mar 1992 |
| 17 | DGH Petroleum, Inc. | | Oil & Gas Operator | Aug 2011 |
| 18 | Diamond Oil, LLC | | Oil & Gas Operator | Oct 2012 |
| 19 | Discus Oil Corporation | | Oil & Gas Operator | Dec 2002 |
| 20 | Diversified Natural Res., Inc. | | Oil Operator | May 2000 |
| 21 | Divine'S Service & Repairs Inc | | Oil & Gas Operator | Mar 1997 |
| 22 | Don Webb | | Oil Operator | Mar 1984 |
| 23 | Donald & Danny Dews Production | | Oil Operator | Jan 2025 |
| 24 | Dossie Dews | | Oil & Gas Operator | Dec 2024 |
| 25 | Drmas, LLC | | Oil & Gas Operator | Nov 2024 |
| 26 | Dual Energy, Inc. | | Oil & Gas Operator | Oct 2022 |
| 27 | Duer Wagner & Company | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 1998 |
| 28 | Dupont Oil Company | | Oil Operator | Feb 1998 |
| 29 | Dzurik Interests, Inc. | | Oil & Gas Operator | Dec 2024 |