| 1 | D & R Enterprises | Eastland, TX 76448 | Oil & Gas Operator | Oct 2020 |
| 2 | D C Energy, Inc. | Oklahoma City, OK 73134 | Oil & Gas Operator | Apr 2020 |
| 3 | D. & D. Operating Account | Breckenridge, TX 76424 | Oil & Gas Operator | Mar 2009 |
| 4 | D.J. & T. Energy | Abilene, TX 79601 | Oil & Gas Operator | Apr 2025 |
| 5 | Dabb Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Aug 2020 |
| 6 | Dale Operating Company | Dallas, TX 75201 | Oil & Gas Operator | Apr 2025 |
| 7 | Dalf Energy LLC | Pampa, TX 79066 | Oil & Gas Operator | Apr 2025 |
| 8 | Dallas Production, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 2021 |
| 9 | Dartex Energy Inc | Graham, TX 76450 | Oil & Gas Operator | Apr 2025 |
| 10 | Daylight Petroleum LLC | Houston, TX 77052 | Oil & Gas Operator | Apr 2025 |
| 11 | DBC Operating Company LLC | Midlothian, TX 76065 | Oil & Gas Operator | Apr 2025 |
| 12 | Dearing, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Mar 2021 |
| 13 | Decleva, Paul | Wichita Falls, TX 76302 | Oil & Gas Operator | Dec 2020 |
| 14 | Delaney Oil And Gas Company | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2025 |
| 15 | Delek Energy Systems Us Inc | Denver, CO 80202 | Oil & Gas Operator | Oct 2011 |
| 16 | Delta Oil & Gas Company | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2003 |
| 17 | Delta Oil & Gas LTD. | Breckenridge, TX 76424 | Oil & Gas Operator | Apr 2025 |
| 18 | Demoss, L. V. | Graham, TX 76450 | Oil & Gas Operator | May 2004 |
| 19 | Denton Exploration, Inc. | Dallas, TX 75219 | Oil & Gas Operator | Apr 2025 |
| 20 | Derby Oil Of Texas | Ventura, CA 93003 | Oil & Gas Operator | May 1996 |
| 21 | Diamond S Energy Company | Fort Worth, TX 76132 | Oil & Gas Operator | Apr 2025 |
| 22 | Dimock Operating Company | Iowa Park, TX 76367 | Oil & Gas Operator | Apr 2025 |
| 23 | Dixie Drilling Company, Inc. | Sherman, TX 75090 | Oil & Gas Operator | Nov 2011 |
| 24 | DJ & T Services, LLC | Abilene, TX 79601 | Oil & Gas Operator | Apr 2025 |
| 25 | DJD Drilling Corporation | Graham, TX 76450 | Oil Operator | Jan 2010 |
| 26 | Dolberry Energy Resources Corp. | Dallas, TX 75252 | Oil Operator | Apr 2025 |
| 27 | Dooley, Jeff | Breckenridge, TX 76424 | Oil & Gas Operator | Jul 2012 |
| 28 | Double Eagle Petroleum Corp | Evansville, IN 47725 | Oil & Gas Operator | Apr 2025 |
| 29 | Double K Production | Graham, TX 76450 | Oil & Gas Operator | Sep 2014 |
| 30 | Double Play Oil & Gas, Inc | Portland, TX 78374 | Oil & Gas Operator | Apr 2025 |
| 31 | Dowell Oil & Gas | Stephenville, TX 76401 | Oil & Gas Operator | Apr 2025 |
| 32 | DP2, LLC | Southlake, TX 76092 | Oil & Gas Operator | Apr 2025 |
| 33 | Dreyfus, Louis Natural Gas Corp | Oklahoma City, OK 73134 | Oil & Gas Operator | Nov 2001 |
| 34 | Dry Fork Production Co., LLC | Wichita Falls, TX 76307 | Oil & Gas Operator | Apr 2025 |