| 1 | R&R Resources Corporation | Houston, TX 77056 | Oil & Gas Operator | Dec 2015 |
| 2 | R. L. Burns Corp. | | Oil & Gas Operator | Feb 1982 |
| 3 | R360 Environmental Solutions Of La, LLC | | Oil Operator | Jan 2025 |
| 4 | Ram Operating Company, Inc. | Houston, TX 77002 | Oil & Gas Operator | Sep 2012 |
| 5 | Rapiere Resources Company | | Oil & Gas Operator | Aug 2024 |
| 6 | Reagan Exploration Company Inc | | Oil & Gas Operator | Nov 1998 |
| 7 | Red Rock Energy Group Inc | | Oil & Gas Operator | Dec 2024 |
| 8 | Renaissance Petroleum Co LLC | Houston, TX 77058 | Oil & Gas Operator | Nov 2011 |
| 9 | Resource Development, Inc. | Stroud, OK 74079 | Oil & Gas Operator | Feb 2007 |
| 10 | Resource Securities Corp. | | Oil & Gas Operator | Mar 2005 |
| 11 | Resources Investment Corp | Denver, CO 80202 | Oil & Gas Operator | Sep 2018 |
| 12 | Roberts & Bunch Resources | | Oil & Gas Operator | Dec 1993 |
| 13 | Robertson Energy, LLC | | Oil & Gas Operator | Dec 2024 |
| 14 | Rogers Oil Co. | Bronson, KS 66716 | Oil & Gas Operator | Sep 1995 |
| 15 | Rollar Oil Co., Inc. | | Oil & Gas Operator | Jul 1999 |
| 16 | Rovig Minerals, Inc. | | Oil & Gas Operator | May 2020 |
| 17 | Roy M. Huffington, Inc. | | Oil & Gas Operator | Jul 1983 |
| 18 | Royalty Management & Dev Corp. | | Oil & Gas Operator | Apr 1998 |
| 19 | Rvo Petroleum Co. | | Oil & Gas Operator | Feb 1982 |