| 1 | D & L Partnership | Rhome, TX 76078 | Oil Operator | May 1987 |
| 2 | D L Operating | Graham, TX 76450 | Oil & Gas Operator | Nov 2024 |
| 3 | D-Mil Production Inc | Argyle, TX 76226 | Oil & Gas Operator | Nov 2024 |
| 4 | Dabb Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Aug 2020 |
| 5 | Dale, Doyle C. | Poolville, TX 76487 | Oil & Gas Operator | Sep 2018 |
| 6 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 7 | Dallas Royalty, Inc. | Jacksboro, TX 76458 | Oil & Gas Operator | Dec 2012 |
| 8 | Dark Horse Operating Co., L.L.C. | Denton, TX 76202 | Oil & Gas Operator | Oct 2022 |
| 9 | Dawson Geophysical Company | Midland, TX 79701 | Oil Operator | Aug 2024 |
| 10 | Decleva, Paul | Wichita Falls, TX 76302 | Oil & Gas Operator | Dec 2020 |
| 11 | Delfin Operating, LLC | Dallas, TX 75243 | Oil & Gas Operator | Nov 2024 |
| 12 | Delta Exploration Company Inc | Denver, CO 80202 | Oil & Gas Operator | Nov 2024 |
| 13 | Denbury Onshore, LLC | Plano, TX 75024 | Oil & Gas Operator | Nov 2024 |
| 14 | Denbury Resources Inc. | Plano, TX 75024 | Oil & Gas Operator | Dec 2003 |
| 15 | Denton Oil & Gas | Argyle, TX 76226 | Oil Operator | Dec 2014 |
| 16 | Devon Energy Operating Co., L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jun 2009 |
| 17 | Devon Energy Production Company LP | Oklahoma City, OK 73102 | Oil & Gas Operator | Nov 2024 |
| 18 | Devon Gas Services, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Aug 2023 |
| 19 | Diamond Energy, Inc. | Sherman, TX 75091 | Oil & Gas Operator | Nov 2024 |
| 20 | Diamond S Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Nov 2024 |
| 21 | Dimock Operating Company | Iowa Park, TX 76367 | Oil & Gas Operator | Nov 2024 |
| 22 | Dimock Petroleum | Dallas, TX 75205 | Oil Operator | Apr 2014 |
| 23 | Diversified Production LLC | Keithville, LA 71047 | Oil & Gas Operator | Nov 2024 |
| 24 | DJ Resources Inc | Bowie, TX 76230 | Oil & Gas Operator | Nov 2017 |
| 25 | Dry Fork Production Co., LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Nov 2024 |
| 26 | Dte Gas Resources, LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Feb 2014 |
| 27 | Dugan Production Corp | Farmington, NM 87499 | Oil & Gas Operator | Sep 2024 |
| 28 | Dune Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Jun 2016 |
| 29 | DWP Oil & Gas | Wichita Falls, TX 76309 | Oil & Gas Operator | Nov 2024 |
| 30 | Dynamic Production, Inc. | Fort Worth, TX 76106 | Oil & Gas Operator | Nov 2024 |