| 1 | D & H Energy, LLC | Shelby, MT 59474 | Oil & Gas Operator | Apr 2026 |
| 2 | D & M Welding LLC | Kevin, MT 59454 | Oil & Gas Operator | Jun 2026 |
| 3 | D.C. Oil | Natalia, TX 78059 | Oil Operator | Jul 2026 |
| 4 | D90 Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Jul 2026 |
| 5 | Dankbar, LLC | Kevin, MT 59454 | Oil Operator | May 2026 |
| 6 | Darrah Oil Company, LLC | Wichita, KS 67201 | Oil & Gas Operator | Jul 2026 |
| 7 | Dart Oil & Gas Corporation | Mason, MI 48854 | Oil & Gas Operator | Jun 2018 |
| 8 | Decker Operating Co., L.L.C. | Houston, TX 77008 | Oil & Gas Operator | Jul 2026 |
| 9 | Delphi International, Inc. | Tulsa, OK 74104 | Oil Operator | Mar 2026 |
| 10 | Denbury Onshore, LLC | Spring, TX 77389 | Oil & Gas Operator | Jul 2026 |
| 11 | Devon Energy Production Company, L.P. | Oklahoma City, OK 73102 | Oil & Gas Operator | Jul 2026 |
| 12 | Devon Energy Williston, L.L.C. | Oklahoma City, OK 73102-8260 | Oil & Gas Operator | May 2026 |
| 13 | Devon Louisiana Corporation | Houston, TX 77002 | Oil & Gas Operator | Oct 2019 |
| 14 | Diamond Oil & Gas LLC | Casper, WY 82604 | Oil & Gas Operator | May 2026 |
| 15 | Digital Operating Company LLC | Boerne, TX 78006 | Oil & Gas Operator | Jul 2026 |
| 16 | Diversified Operating Corp. | Golden, CO 80401 | Oil & Gas Operator | Oct 2012 |
| 17 | DL Energy, LLC | Saco, MT 59261 | Gas Operator | Apr 2026 |
| 18 | DNR Oil And Gas, Inc. | Englewood, CO 80155 | Oil & Gas Operator | Jun 2026 |
| 19 | Dominion Oklahoma Texas Exploration & Production | Houston, TX 77060 | Oil & Gas Operator | Dec 2006 |
| 20 | Drawings, LLC | Albuquerque, NM 87109 | Oil Operator | Aug 2025 |
| 21 | Dry Coulee Oil & Gas Company | Oilmont, MT 59466 | Oil Operator | Oct 2003 |