| 201 | Robco Investments, Inc. | | Oil & Gas Operator | Jul 2016 |
| 202 | Roberson Farm Equipment, Inc. | | Oil Operator | Mar 1989 |
| 203 | Roberson Well Service | | Gas Operator | Jun 2024 |
| 204 | Robert A Craig | | Oil Operator | Jul 2020 |
| 205 | Robert C. Pettit | | Oil & Gas Operator | Feb 1986 |
| 206 | Robert D Valerius Inc. | | Oil Operator | Mar 1996 |
| 207 | Robert E McDowell | | Oil Operator | Dec 1998 |
| 208 | Robert G Cox & Assoc La Inc. | | Oil & Gas Operator | Jun 1994 |
| 209 | Robert K. Freeman | | Oil Operator | Jul 1991 |
| 210 | Robert L. Waterbury | | Oil & Gas Operator | Nov 2001 |
| 211 | Robert L. Waterbury, L.L.C. | | Oil & Gas Operator | Jun 2024 |
| 212 | Robert M. Mills | | Oil Operator | Oct 2017 |
| 213 | Robert P. Artzberger | | Oil & Gas Operator | Dec 1979 |
| 214 | Robert S. Barnwell, III | | Oil & Gas Operator | Oct 1984 |
| 215 | Robert W. Omeara | | Oil & Gas Operator | Sep 1988 |
| 216 | Roberts & Bunch Resources | | Oil & Gas Operator | Dec 1993 |
| 217 | Roberts Oil Corp. | | Oil & Gas Operator | Sep 1982 |
| 218 | Robertson Energy, LLC | | Oil & Gas Operator | Jul 2024 |
| 219 | Robie A. Bridges III | | Oil Operator | Aug 1993 |
| 220 | Robinett Resources Inc. | Longview, TX 75601 | Oil & Gas Operator | Dec 1999 |
| 221 | Roblyn Petroleum Corp. | | Oil & Gas Operator | May 1983 |
| 222 | Rock Creek Oil, Inc. | Dallas, TX 75225 | Oil & Gas Operator | Nov 2019 |
| 223 | Rock Energy Operating Company | | Oil & Gas Operator | Nov 2008 |
| 224 | Rock Energy, Inc. | | Oil & Gas Operator | Sep 1992 |
| 225 | Rock Well Petroleum (U.S.), Inc. | Canada, 00100 | Oil & Gas Operator | Sep 2014 |
| 226 | Rockbridge Oil & Gas | Houston, TX 77027 | Oil & Gas Operator | Mar 1990 |
| 227 | Rockcliff Operating La LLC | | Oil & Gas Operator | Jul 2022 |
| 228 | Rockland Oil Company | Addison, TX 75001 | Oil & Gas Operator | Aug 2024 |
| 229 | Rockleigh K. Thurman | | Oil & Gas Operator | Jul 2024 |
| 230 | Rocky Mount Gas Gathering,LLC | | Oil Operator | Apr 2001 |
| 231 | Rodessa Operating Company | Corpus Chrsti, TX 78426 | Oil & Gas Operator | Dec 2024 |
| 232 | Roger Wilson | | Oil Operator | Apr 2002 |
| 233 | Roger Wilson, Inc. | | Oil Operator | Jul 2019 |
| 234 | Rogers Oil Co. | Bronson, KS 66716 | Oil & Gas Operator | Sep 1995 |
| 235 | Rojo Oil Company | McLean, TX 79057 | Oil & Gas Operator | Dec 2024 |
| 236 | Rollar Oil Co., Inc. | | Oil & Gas Operator | Jul 1999 |
| 237 | Romaxsco Exploration Co., Inc. | | Oil & Gas Operator | Aug 1993 |
| 238 | Roms Co., Inc. | | Oil Operator | Jun 1983 |
| 239 | Ron Knott & Associates,Inc. | | Oil & Gas Operator | Aug 1989 |
| 240 | Ronald E. Hall | | Oil Operator | Nov 1991 |
| 241 | Ronny N. Davis | | Oil Operator | Jul 2024 |
| 242 | Rooster Petroleum, LLC | | Oil & Gas Operator | Feb 2011 |
| 243 | Rooster Production, LLC | Oil City, LA 71061 | Oil Operator | Dec 2024 |
| 244 | Rosamond Drilling Co., Inc. | | Gas Operator | Nov 1984 |
| 245 | Rosbottom Petroleum | | Oil & Gas Operator | Aug 1988 |
| 246 | Rosbottom Production Corp | Shreveport, LA 71134 | Oil & Gas Operator | Dec 2017 |
| 247 | Rose Pass Mines, Inc. | | Oil Operator | Oct 1982 |
| 248 | Rosestone Operating Company, LLC | | Oil & Gas Operator | May 2024 |
| 249 | Rosetta Resources Operating LP | San Antonio, TX 78216 | Oil & Gas Operator | Dec 2024 |
| 250 | Rosewood Resources (HPC), Inc. | | Gas Operator | Dec 1984 |
| 251 | Rosewood Resources (Poc), Inc. | | Oil & Gas Operator | Dec 1984 |
| 252 | Rosewood Resources, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Dec 2024 |
| 253 | Ross & Glenn Petroleum Inc. | | Oil & Gas Operator | Aug 1984 |
| 254 | Ross Exploration,Inc. | Fort Worth, TX 76102 | Oil & Gas Operator | Jul 2013 |
| 255 | Ross Prod. - Zwahlen & Raish | | Oil & Gas Operator | Sep 1998 |
| 256 | Ross Production Co. | Shreveport, LA 71101 | Oil & Gas Operator | Mar 2000 |
| 257 | Roughneck L.L.C. | | Oil Operator | Jul 2024 |
| 258 | Rouxopco LLC | | Oil Operator | May 2024 |
| 259 | Rovig Minerals, Inc. | | Oil & Gas Operator | May 2020 |
| 260 | Rowe Oil And Gas, Inc. | | Oil & Gas Operator | May 1999 |
| 261 | Rowe Oil Co. | | Oil Operator | Jan 2002 |
| 262 | Rowe, Inc. | | Oil & Gas Operator | Jun 1992 |
| 263 | Roxanna Acadia, LLC | | Oil & Gas Operator | May 2023 |
| 264 | Roy D. Gish | | Oil & Gas Operator | Sep 2019 |
| 265 | Roy M. Huffington, Inc. | | Oil & Gas Operator | Jul 1983 |
| 266 | Roy M. Teel | | Oil & Gas Operator | Nov 1983 |
| 267 | Royal Petroleum Corp. | Dallas, TX 75229 | Oil & Gas Operator | Jul 2024 |
| 268 | Royal Production Company, Inc. | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Dec 2024 |
| 269 | Royalty Management & Dev Corp. | | Oil & Gas Operator | Apr 1998 |
| 270 | Rozel Operating Company | | Oil & Gas Operator | Oct 2014 |
| 271 | RPS Energy, Inc. | | Oil & Gas Operator | Jul 2020 |
| 272 | Rse, Inc. | Houston, TX 77077 | Oil & Gas Operator | Sep 2000 |
| 273 | Ruby Breaux Gotreaux | | Oil Operator | Mar 1981 |
| 274 | Rudman Resources, Inc. | | Oil Operator | Jul 1981 |
| 275 | Rusk Co. Well Service Co., Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2024 |
| 276 | Rusk Energy Management, LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2008 |
| 277 | Ruskin H Meyer Et Al | | Oil Operator | Sep 1987 |
| 278 | Russell A. Flowers | | Oil Operator | May 1995 |
| 279 | Russell Resources, Inc. | | Oil & Gas Operator | Dec 1998 |
| 280 | Rutherford Oil Corporation | Houston, TX 77046 | Oil & Gas Operator | Jun 2019 |
| 281 | Rvo Petroleum Co. | | Oil & Gas Operator | Feb 1982 |
| 282 | Ryca Energy Partners LLC | | Oil Operator | May 2024 |
| 283 | Ryca Energy, LLC | | Oil & Gas Operator | Mar 2015 |