| 1 | R & D Holdings, Inc. | | Gas Operator | Feb 1991 |
| 2 | R. W. Ellington, Jr. | | Gas Operator | May 1985 |
| 3 | Rabalais Oil And Gas, Inc. | | Oil & Gas Operator | Sep 2023 |
| 4 | Rabun Resources | | Gas Operator | Jan 2025 |
| 5 | Relco Exploration Co., Inc. | | Gas Operator | Aug 1987 |
| 6 | Reliance TR-JV | | Gas Operator | Apr 1988 |
| 7 | Reliance Trusts | Dallas, TX 75244 | Oil & Gas Operator | Nov 1995 |
| 8 | Reliance Trusts HS | | Gas Operator | Feb 1989 |
| 9 | Reliant Energy Field SVS Inc. | | Oil Operator | Sep 2002 |
| 10 | Richard T. Perry | | Gas Operator | May 1993 |
| 11 | River Energy Co., Inc. | | Gas Operator | Dec 2012 |
| 12 | Riverstone Energy Operating, LLC | Houston, TX 77090 | Oil & Gas Operator | May 2026 |
| 13 | RLM Energy Company Inc. | Monroe, LA 71201 | Oil & Gas Operator | Mar 2008 |
| 14 | RMR Oil Company | Jacksboro, TX 76458 | Oil & Gas Operator | Sep 2005 |
| 15 | Roberson Well Service | | Gas Operator | Dec 2024 |
| 16 | Rosamond Drilling Co., Inc. | | Gas Operator | Nov 1984 |
| 17 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 18 | Rosestone Operating Company, LLC | | Oil & Gas Operator | Dec 2024 |
| 19 | Rowe, Inc. | | Oil & Gas Operator | Jun 1992 |
| 20 | Roy M. Teel | | Oil & Gas Operator | Nov 1983 |