| 4001 | Rockbridge Oil & Gas | Houston, TX 77027 | Oil & Gas Operator | Mar 1990 |
| 4002 | Rockcliff Operating La LLC | | Oil & Gas Operator | Jul 2022 |
| 4003 | Rockland Oil Company | Addison, TX 75001 | Oil & Gas Operator | Aug 2025 |
| 4004 | Rockleigh K. Thurman | | Oil & Gas Operator | Jan 2025 |
| 4005 | Rocky Mount Gas Gathering,LLC | | Oil Operator | Apr 2001 |
| 4006 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Dec 2025 |
| 4007 | Roger Wilson | | Oil Operator | Apr 2002 |
| 4008 | Roger Wilson, Inc. | | Oil Operator | Jul 2019 |
| 4009 | Rogers Oil Co. | Bronson, KS 66716 | Oil & Gas Operator | Sep 1995 |
| 4010 | Rojo Oil Company | McLean, TX 79057 | Oil & Gas Operator | Dec 2025 |
| 4011 | Rollar Oil Co., Inc. | | Oil & Gas Operator | Jul 1999 |
| 4012 | Romaxsco Exploration Co., Inc. | | Oil & Gas Operator | Aug 1993 |
| 4013 | Roms Co., Inc. | | Oil Operator | Jun 1983 |
| 4014 | Ron Knott & Associates,Inc. | | Oil & Gas Operator | Aug 1989 |
| 4015 | Ronald E. Hall | | Oil Operator | Nov 1991 |
| 4016 | Ronny N. Davis | | Oil Operator | Jan 2025 |
| 4017 | Rooster Petroleum, LLC | | Oil & Gas Operator | Feb 2011 |
| 4018 | Rooster Production, LLC | Oil City, LA 71061 | Oil Operator | Jan 2025 |
| 4019 | Roppolo Petro/Sun Explor& Prod | | Oil & Gas Operator | Sep 1988 |
| 4020 | Rosamond Drilling Co., Inc. | | Gas Operator | Nov 1984 |
| 4021 | Rosbottom Petroleum | | Oil & Gas Operator | Aug 1988 |
| 4022 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 4023 | Rose Pass Mines, Inc. | | Oil Operator | Oct 1982 |
| 4024 | Rosestone Operating Company, LLC | | Oil & Gas Operator | Dec 2024 |
| 4025 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Dec 2025 |
| 4026 | Rosewood Resources (HPC), Inc. | | Gas Operator | Dec 1984 |
| 4027 | Rosewood Resources (Poc), Inc. | | Oil & Gas Operator | Dec 1984 |
| 4028 | Rosewood Resources Inc | Dallas, TX 75201 | Oil & Gas Operator | Dec 2025 |
| 4029 | Ross & Glenn Petroleum Inc. | | Oil & Gas Operator | Aug 1984 |
| 4030 | Ross Exploration,Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2013 |
| 4031 | Ross Prod. - Zwahlen & Raish | | Oil & Gas Operator | Sep 1998 |
| 4032 | Ross Production Co. | Shreveport, LA 71101 | Oil & Gas Operator | Mar 2000 |
| 4033 | Ross-A. J. Hodges Ind. | | Oil & Gas Operator | Dec 1980 |
| 4034 | Roughneck L.L.C. | | Oil Operator | Jan 2025 |
| 4035 | Rouxopco LLC | | Oil Operator | Dec 2024 |
| 4036 | Rovig Minerals, Inc. | | Oil & Gas Operator | May 2020 |
| 4037 | Rowe Oil And Gas, Inc. | | Oil & Gas Operator | Jun 1999 |
| 4038 | Rowe Oil Co. | | Oil Operator | Jan 2002 |
| 4039 | Rowe, Inc. | | Oil & Gas Operator | Jun 1992 |
| 4040 | Roxanna Acadia, LLC | | Oil & Gas Operator | May 2023 |
| 4041 | Roy D. Gish | | Oil & Gas Operator | Sep 2019 |
| 4042 | Roy M. Huffington, Inc. | | Oil & Gas Operator | Jul 1983 |
| 4043 | Roy M. Teel | | Oil & Gas Operator | Nov 1983 |
| 4044 | Royal Petroleum Corp. | Dallas, TX 75229 | Oil & Gas Operator | Jan 2025 |
| 4045 | Royal Production Company, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2025 |
| 4046 | Royalty Management & Dev Corp. | | Oil & Gas Operator | Apr 1998 |
| 4047 | Rozel Operating Company | | Oil & Gas Operator | Oct 2014 |
| 4048 | RPS Energy, Inc. | | Oil & Gas Operator | Jul 2020 |
| 4049 | Rse, Inc. | Houston, TX 77077 | Oil & Gas Operator | Sep 2000 |
| 4050 | Ruby Breaux Gotreaux | | Oil Operator | Mar 1981 |
| 4051 | Rudman Resources, Inc. | | Oil Operator | Jul 1981 |
| 4052 | Rusk Co. Well Service Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 4053 | Rusk Energy Management, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2008 |
| 4054 | Ruskin H Meyer Et Al | | Oil Operator | Sep 1987 |
| 4055 | Russell A. Flowers | | Oil Operator | May 1995 |
| 4056 | Russell Resources, Inc. | | Oil & Gas Operator | Dec 1998 |
| 4057 | Rutherford Oil Corporation | Houston, TX 77046 | Oil & Gas Operator | Jun 2019 |
| 4058 | Rvo Petroleum Co. | | Oil & Gas Operator | Feb 1982 |
| 4059 | Ryca Energy Partners LLC | | Oil Operator | Nov 2024 |
| 4060 | Ryca Energy, LLC | | Oil & Gas Operator | Mar 2015 |
| 4061 | S & J Operating Company | Wichita Falls, TX 76301 | Oil & Gas Operator | Mar 2015 |
| 4062 | S & S Oil Company | Electra, TX 76360 | Oil & Gas Operator | Dec 2025 |
| 4063 | S & S Operating Company, Inc. | Winnie, TX 77665 | Oil & Gas Operator | Dec 2025 |
| 4064 | S S M Partnership | | Oil & Gas Operator | Jul 1992 |
| 4065 | S&B Petroleum Corporation | | Oil & Gas Operator | Jun 1994 |
| 4066 | S&S Williams Inc | | Oil Operator | May 2004 |
| 4067 | S. G. Myers, Jr. | | Oil & Gas Operator | May 2005 |
| 4068 | S. G. Myers, Jr. Et Al | | Oil & Gas Operator | Jul 1991 |
| 4069 | S. Parish Oil Company, Inc. | | Oil & Gas Operator | Dec 1997 |
| 4070 | S. S. Tatum | | Oil Operator | Aug 1999 |
| 4071 | S. W. Ray, Et Al | | Oil Operator | Mar 2003 |
| 4072 | S.H. Loe Oil Corp. | | Oil & Gas Operator | Jan 2025 |
| 4073 | S2 Energy 1, LP | | Oil & Gas Operator | Nov 2012 |
| 4074 | S2 Energy Operating LLC | | Oil & Gas Operator | May 2023 |
| 4075 | Saba Energy Of Texas Inc | Houston, TX 77042 | Oil & Gas Operator | Jul 2007 |
| 4076 | Sabine Corporation | Oklahoma City, OK 73116 | Oil & Gas Operator | Jul 1996 |
| 4077 | Sabine Oil & Gas Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2025 |
| 4078 | Sabine Oil & Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2017 |
| 4079 | Sabine Pipe & Supply Co. | Kilgore, TX 75663 | Oil & Gas Operator | Sep 2004 |
| 4080 | Sabine Pipe, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2025 |
| 4081 | Sable Minerals, Inc. | | Oil & Gas Operator | Nov 1993 |
| 4082 | Sabre Operating, Inc. | Wichita Falls, TX 76308 | Oil & Gas Operator | Dec 2025 |
| 4083 | Sackett Oil Company | | Oil & Gas Operator | Oct 1995 |
| 4084 | Sage Energy Company | San Antonio, TX 78215 | Oil & Gas Operator | Dec 2025 |
| 4085 | Sahara Gas & Exploration, Inc. | | Gas Operator | Mar 2002 |
| 4086 | Saline Injection Systems Co. | | Oil Operator | Jan 2025 |
| 4087 | Sally Oil Company | | Oil Operator | Sep 2016 |
| 4088 | Sam Aertker | | Oil Operator | Jul 1992 |
| 4089 | Sam Jones & Assoc Prod Div Inc | | Oil & Gas Operator | Feb 1999 |
| 4090 | Sam Myers | | Oil & Gas Operator | Nov 1988 |
| 4091 | Sam R. Brown | | Oil Operator | Mar 1987 |
| 4092 | Sam Spears, Jr. | | Oil & Gas Operator | Sep 1998 |
| 4093 | Samantha Petroleum Corp. | | Oil & Gas Operator | Apr 1987 |
| 4094 | Samedan Oil Corp. Et Al | | Oil & Gas Operator | Jan 1989 |
| 4095 | Samedan Oil Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2019 |
| 4096 | Sammy D. Thrash | | Oil & Gas Operator | May 2012 |
| 4097 | Sammy D. Thrash, LLC | | Oil & Gas Operator | May 2019 |
| 4098 | Sample Exploration | | Oil & Gas Operator | Jul 2002 |
| 4099 | Samson Contour Energy E&P, LLC | Tulsa, OK 74103 | Oil & Gas Operator | Sep 2017 |
| 4100 | Samson Exploration LLC | Tulsa, OK 74101 | Oil & Gas Operator | Oct 2025 |