| 3901 | Riseden, LTD | | Oil & Gas Operator | Nov 1989 |
| 3902 | Risher Company, Inc. | | Oil & Gas Operator | Jul 2001 |
| 3903 | Rising Star 2000 Oil & Gas, Inc. | | Oil Operator | Dec 2024 |
| 3904 | Rising Star Energy, L.L.C. | Dallas, TX 75219 | Oil & Gas Operator | Aug 2006 |
| 3905 | Rising Star Energy-Oper Co., LLC | | Oil & Gas Operator | Nov 2006 |
| 3906 | River Bend Operating, Inc. | | Oil & Gas Operator | Jul 1999 |
| 3907 | River City Resources, Inc. | Tulsa, OK 74119 | Oil & Gas Operator | Nov 1997 |
| 3908 | River Energy Co., Inc. | | Gas Operator | Dec 2012 |
| 3909 | River Rouge Minerals | | Oil & Gas Operator | Dec 2024 |
| 3910 | River Rouge Minerals Inc | | Oil & Gas Operator | Mar 1981 |
| 3911 | Riverside Resources, Inc. | | Oil & Gas Operator | Oct 2015 |
| 3912 | Riverstone Energy Operating, LLC | Houston, TX 77090 | Oil & Gas Operator | Jul 2026 |
| 3913 | Riverwood Production Co., Inc. | | Oil & Gas Operator | Nov 1990 |
| 3914 | Riviera Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | May 2026 |
| 3915 | RLM Energy Company Inc. | Monroe, LA 71201 | Oil & Gas Operator | Mar 2008 |
| 3916 | RLS Partnership | | Oil Operator | Apr 1983 |
| 3917 | Rme Petroleum Company | Houston, TX 77251 | Oil & Gas Operator | Nov 2016 |
| 3918 | RMR Oil Company | Jacksboro, TX 76458 | Oil & Gas Operator | Sep 2005 |
| 3919 | RMT Resources LLC | | Oil Operator | Jan 2025 |
| 3920 | Robco Investments, Inc. | | Oil & Gas Operator | Jul 2016 |
| 3921 | Roberson Farm Equipment, Inc. | | Oil Operator | Mar 1989 |
| 3922 | Roberson Well Service | | Gas Operator | Dec 2024 |
| 3923 | Robert A Craig | | Oil Operator | Jul 2020 |
| 3924 | Robert C. Pettit | | Oil & Gas Operator | Feb 1986 |
| 3925 | Robert D Valerius Inc. | | Oil Operator | Mar 1996 |
| 3926 | Robert E McDowell | | Oil Operator | Dec 1998 |
| 3927 | Robert G Cox & Assoc La Inc. | | Oil & Gas Operator | Jun 1994 |
| 3928 | Robert K. Freeman | | Oil Operator | Jul 1991 |
| 3929 | Robert L. Waterbury | | Oil & Gas Operator | Nov 2001 |
| 3930 | Robert L. Waterbury, L.L.C. | | Oil & Gas Operator | Dec 2024 |
| 3931 | Robert M. Mills | | Oil Operator | Oct 2017 |
| 3932 | Robert P. Artzberger | | Oil & Gas Operator | Dec 1979 |
| 3933 | Robert S. Barnwell, III | | Oil & Gas Operator | Oct 1984 |
| 3934 | Robert W. Omeara | | Oil & Gas Operator | Sep 1988 |
| 3935 | Roberts & Bunch Resources | | Oil & Gas Operator | Dec 1993 |
| 3936 | Roberts Oil Corp. | | Oil & Gas Operator | Sep 1982 |
| 3937 | Robertson Energy, LLC | | Oil & Gas Operator | Dec 2024 |
| 3938 | Robie A. Bridges III | | Oil Operator | Aug 1993 |
| 3939 | Robinett Resources Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 1999 |
| 3940 | Roblyn Petroleum Corp. | | Oil & Gas Operator | May 1983 |
| 3941 | Rock Creek Oil, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Nov 2019 |
| 3942 | Rock Energy Operating Company | | Oil & Gas Operator | Nov 2008 |
| 3943 | Rock Energy, Inc. | | Oil & Gas Operator | Sep 1992 |
| 3944 | Rock Well Petroleum (U.S.), Inc. | Canada, 00100 | Oil & Gas Operator | Sep 2014 |
| 3945 | Rockbridge Oil & Gas | Houston, TX 77027 | Oil & Gas Operator | Mar 1990 |
| 3946 | Rockcliff Operating La LLC | | Oil & Gas Operator | Jul 2022 |
| 3947 | Rockland Oil Company | Addison, TX 75001 | Oil & Gas Operator | Apr 2026 |
| 3948 | Rockleigh K. Thurman | | Oil & Gas Operator | Jan 2025 |
| 3949 | Rocky Mount Gas Gathering,LLC | | Oil Operator | Apr 2001 |
| 3950 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Jul 2026 |
| 3951 | Roger Wilson | | Oil Operator | Apr 2002 |
| 3952 | Roger Wilson, Inc. | | Oil Operator | Jul 2019 |
| 3953 | Rogers Oil Co. | Bronson, KS 66716 | Oil & Gas Operator | Sep 1995 |
| 3954 | Rojo Oil Company | McLean, TX 79057 | Oil & Gas Operator | Jul 2026 |
| 3955 | Rollar Oil Co., Inc. | | Oil & Gas Operator | Jul 1999 |
| 3956 | Romaxsco Exploration Co., Inc. | | Oil & Gas Operator | Aug 1993 |
| 3957 | Roms Co., Inc. | | Oil Operator | Jun 1983 |
| 3958 | Ron Knott & Associates,Inc. | | Oil & Gas Operator | Aug 1989 |
| 3959 | Ronald E. Hall | | Oil Operator | Nov 1991 |
| 3960 | Ronny N. Davis | | Oil Operator | Jan 2025 |
| 3961 | Rooster Petroleum, LLC | | Oil & Gas Operator | Feb 2011 |
| 3962 | Rooster Production, LLC | Oil City, LA 71061 | Oil Operator | Jan 2025 |
| 3963 | Roppolo Petro/Sun Explor& Prod | | Oil & Gas Operator | Sep 1988 |
| 3964 | Rosamond Drilling Co., Inc. | | Gas Operator | Nov 1984 |
| 3965 | Rosbottom Petroleum | | Oil & Gas Operator | Aug 1988 |
| 3966 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 3967 | Rose Pass Mines, Inc. | | Oil Operator | Oct 1982 |
| 3968 | Rosestone Operating Company, LLC | | Oil & Gas Operator | Dec 2024 |
| 3969 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Jul 2026 |
| 3970 | Rosewood Resources (HPC), Inc. | | Gas Operator | Dec 1984 |
| 3971 | Rosewood Resources (Poc), Inc. | | Oil & Gas Operator | Dec 1984 |
| 3972 | Rosewood Resources Inc | Dallas, TX 75201 | Oil & Gas Operator | Jul 2026 |
| 3973 | Ross & Glenn Petroleum Inc. | | Oil & Gas Operator | Aug 1984 |
| 3974 | Ross Exploration,Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2013 |
| 3975 | Ross Prod. - Zwahlen & Raish | | Oil & Gas Operator | Sep 1998 |
| 3976 | Ross Production Co. | Shreveport, LA 71101 | Oil & Gas Operator | Mar 2000 |
| 3977 | Roughneck L.L.C. | | Oil Operator | Jan 2025 |
| 3978 | Rouxopco LLC | | Oil Operator | Dec 2024 |
| 3979 | Rovig Minerals, Inc. | | Oil & Gas Operator | May 2020 |
| 3980 | Rowe Oil And Gas, Inc. | | Oil & Gas Operator | Jun 1999 |
| 3981 | Rowe Oil Co. | | Oil Operator | Jan 2002 |
| 3982 | Rowe, Inc. | | Oil & Gas Operator | Jun 1992 |
| 3983 | Roxanna Acadia, LLC | | Oil & Gas Operator | May 2023 |
| 3984 | Roy D. Gish | | Oil & Gas Operator | Sep 2019 |
| 3985 | Roy M. Huffington, Inc. | | Oil & Gas Operator | Jul 1983 |
| 3986 | Roy M. Teel | | Oil & Gas Operator | Nov 1983 |
| 3987 | Royal Petroleum Corp. | Dallas, TX 75229 | Oil & Gas Operator | Jan 2025 |
| 3988 | Royal Production Company, Inc. | Corpus Christ, TX 78401 | Oil & Gas Operator | Jul 2026 |
| 3989 | Royalty Management & Dev Corp. | | Oil & Gas Operator | Apr 1998 |
| 3990 | Rozel Operating Company | | Oil & Gas Operator | Oct 2014 |
| 3991 | RPS Energy, Inc. | | Oil & Gas Operator | Jul 2020 |
| 3992 | Rse, Inc. | Houston, TX 77077 | Oil & Gas Operator | Sep 2000 |
| 3993 | Ruby Breaux Gotreaux | | Oil Operator | Mar 1981 |
| 3994 | Rudman Resources, Inc. | | Oil Operator | Jul 1981 |
| 3995 | Rusk Co. Well Service Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Jul 2026 |
| 3996 | Rusk Energy Management, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2008 |
| 3997 | Ruskin H Meyer Et Al | | Oil Operator | Sep 1987 |
| 3998 | Russell A. Flowers | | Oil Operator | May 1995 |
| 3999 | Russell Resources, Inc. | | Oil & Gas Operator | Dec 1998 |
| 4000 | Rutherford Oil Corporation | Houston, TX 77046 | Oil & Gas Operator | Jun 2019 |