| 1 | R H Energy Co Inc | | Oil & Gas Operator | Sep 1989 |
| 2 | R. & F. Land Company | | Oil & Gas Operator | Jan 2000 |
| 3 | R. D. Briscoe, Inc. | | Oil & Gas Operator | Nov 2024 |
| 4 | R/C Holdings, Inc. | | Oil & Gas Operator | Dec 1991 |
| 5 | Ralph L. Leaderbrand | | Oil & Gas Operator | Dec 1996 |
| 6 | Ram Energy LLC (Ok) | | Oil & Gas Operator | Feb 2018 |
| 7 | Ram Management Company, Inc. | | Oil & Gas Operator | Sep 1984 |
| 8 | RCV Investments, LLC | | Oil & Gas Operator | Jan 2025 |
| 9 | RDT Properties, Inc. | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2012 |
| 10 | Redd Production Of Mansfield | | Oil & Gas Operator | Jan 1991 |
| 11 | Redmon Oil Company, Inc., The | Plano, TX 75023 | Oil & Gas Operator | Oct 2025 |
| 12 | Regency Field Services LLC | Dallas, TX 75201 | Oil Operator | Jul 2017 |
| 13 | Reliant Energy Field SVS Inc. | | Oil Operator | Sep 2002 |
| 14 | Remuda Oil & Gas Corp. | | Oil & Gas Operator | Aug 1987 |
| 15 | Remuda Operating Company | Midland, TX 79711 | Oil & Gas Operator | Oct 2025 |
| 16 | Retsal Drilling Co. | | Oil & Gas Operator | Jan 1984 |
| 17 | Retsal Production Company | | Oil & Gas Operator | Mar 1986 |
| 18 | Revilo Exploration, Inc. | Richardson, TX 75081 | Oil & Gas Operator | Jul 2021 |
| 19 | Reynolds Drilling Co., Inc. | Shreveport, LA 71105 | Oil & Gas Operator | Oct 2025 |
| 20 | Richard C. Hinds | | Oil Operator | Jan 2025 |
| 21 | Rising Star Energy-Oper Co., LLC | | Oil & Gas Operator | Nov 2006 |
| 22 | River Rouge Minerals | | Oil & Gas Operator | Dec 2024 |
| 23 | Robert S. Barnwell, III | | Oil & Gas Operator | Oct 1984 |
| 24 | Rockcliff Operating La LLC | | Oil & Gas Operator | Jul 2022 |
| 25 | Ron Knott & Associates,Inc. | | Oil & Gas Operator | Aug 1989 |
| 26 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 27 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Oct 2025 |
| 28 | Ross & Glenn Petroleum Inc. | | Oil & Gas Operator | Aug 1984 |
| 29 | Ross Exploration,Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2013 |
| 30 | Roughneck L.L.C. | | Oil Operator | Jan 2025 |