| 1 | R & B Oil Company, LLC Of Texas | | Oil & Gas Operator | Jan 2025 |
| 2 | R. J. Davenport | | Oil Operator | May 1985 |
| 3 | Radke Oil Co., Inc. | | Oil Operator | May 2001 |
| 4 | Ramco Exploration, Inc. | | Oil & Gas Operator | Feb 1998 |
| 5 | Ramco, Inc. | | Oil & Gas Operator | May 1992 |
| 6 | Range Production Company | Fort Worth, TX 76102 | Oil & Gas Operator | Sep 2021 |
| 7 | Red River Oil & Gas Inc. | | Oil & Gas Operator | May 2012 |
| 8 | Red Wing Oil & Gas, Inc. | | Oil Operator | Sep 1990 |
| 9 | Redman Operating Company | Houston, TX 77042 | Oil & Gas Operator | May 2008 |
| 10 | Reliable Prod Service Inc. | | Oil Operator | Mar 2007 |
| 11 | Rental & Fishing Tools, Inc. | | Oil Operator | Dec 2024 |
| 12 | Republic Prod.Co.Of Tex., Inc | | Oil & Gas Operator | Jun 1981 |
| 13 | Resource Securities Corp. | | Oil & Gas Operator | Mar 2005 |
| 14 | Resources Investment Corp | Denver, CO 80202 | Oil & Gas Operator | Sep 2018 |
| 15 | Riceland Petroleum Company | | Oil & Gas Operator | Nov 2024 |
| 16 | Ridgeway Exco, Inc. | San Antonio, TX 78279 | Oil & Gas Operator | Mar 1996 |
| 17 | Rio Bravo Oil Company | The Woodlands, TX 77381 | Oil & Gas Operator | Feb 2002 |
| 18 | Riseden, LTD | | Oil & Gas Operator | Nov 1989 |
| 19 | RLP Gulf States, L.L.C. | | Oil & Gas Operator | Apr 2012 |
| 20 | Rockbridge Oil & Gas | Houston, TX 77027 | Oil & Gas Operator | Mar 1990 |
| 21 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Oct 2025 |
| 22 | Ross-A. J. Hodges Ind. | | Oil & Gas Operator | Dec 1980 |
| 23 | Roy M. Teel | | Oil & Gas Operator | Nov 1983 |
| 24 | Rozel Operating Company | | Oil & Gas Operator | Oct 2014 |
| 25 | Ruby Breaux Gotreaux | | Oil Operator | Mar 1981 |
| 26 | Rvo Petroleum Co. | | Oil & Gas Operator | Feb 1982 |