| 201 | Empire Oil Company | Coppell, TX 75019 | Oil & Gas Operator | May 2024 |
| 202 | Empire Oil Of New Jersey | Post, TX 79356 | Oil & Gas Operator | Jan 1999 |
| 203 | Empire Operating, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Mar 2017 |
| 204 | Empire Texas Operating LLC | Tulsa, OK 74114 | Oil & Gas Operator | May 2024 |
| 205 | Empresa Energy, LP | Houston, TX 77024 | Oil & Gas Operator | Jul 2009 |
| 206 | En Geo, Inc. | Richardson, TX 75081 | Oil & Gas Operator | May 2024 |
| 207 | Enable Midstream Partners, LP | Oklahoma City, OK 73124 | Oil Operator | Sep 2023 |
| 208 | Enbridge G & P (East Texas) L.P. | Houston, TX 77056 | Oil & Gas Operator | Sep 2018 |
| 209 | Enbridge Pipelines (Ne Texas) LP | Houston, TX 77002 | Oil & Gas Operator | Jan 2010 |
| 210 | Encana Oil & Gas (USA) Inc. | Denver, CO 80202 | Oil & Gas Operator | Oct 2020 |
| 211 | Encina Resources, LLC | Houston, TX 77251 | Oil & Gas Operator | May 2024 |
| 212 | Encino Exploration, Inc. | George West, TX 78022 | Oil & Gas Operator | May 2024 |
| 213 | Encino Operating LLC | Houston, TX 77057 | Oil & Gas Operator | May 2024 |
| 214 | Enco Exploration Company | Corpus Chrsti, TX 78401 | Oil & Gas Operator | Apr 2020 |
| 215 | Enco Resources Inc. | Kingwood, TX 77325 | Oil & Gas Operator | May 2024 |
| 216 | Encon Services, Inc. | Abilene, TX 79608 | Oil & Gas Operator | May 2024 |
| 217 | Encore Energy Partners Operating LLC | Houston, TX 77057 | Oil & Gas Operator | Apr 2015 |
| 218 | Encore Energy, Inc. | Gainesville, TX 76241 | Oil & Gas Operator | Mar 2015 |
| 219 | Encore Operating Company | Denver, CO 80227 | Oil & Gas Operator | Jan 2024 |
| 220 | Encore Operating LP | Plano, TX 75024 | Oil & Gas Operator | Feb 2024 |
| 221 | Encore Permian Operating, LLC | Minneapolis, MN 55401 | Oil & Gas Operator | May 2024 |
| 222 | Encrescent, LLC | Dallas, TX 75205 | Oil & Gas Operator | May 2024 |
| 223 | Endeavor Energy Resources, LP | Midland, TX 79701 | Oil & Gas Operator | May 2024 |
| 224 | Endeavor Natural Gas LLC | Houston, TX 77002 | Oil & Gas Operator | Feb 2015 |
| 225 | Endeavor Natural Gas, LP | Houston, TX 77002 | Oil & Gas Operator | May 2024 |
| 226 | Endeavor Production Company | San Angelo, TX 76904 | Oil & Gas Operator | Mar 2008 |
| 227 | Enderli Oil Company, Inc | Highlands, TX 77562 | Oil & Gas Operator | Aug 2003 |
| 228 | Endurance Oil & Gas, Inc. | Minden, LA 71055 | Oil & Gas Operator | Apr 2023 |
| 229 | Endurance Resources III Operating , LLC | Addison, TX 75001 | Oil & Gas Operator | May 2024 |
| 230 | Endurance Resources LLC | Addison, TX 75001 | Oil & Gas Operator | Apr 2017 |
| 231 | Enduring Resources, LLC | Greenwood VLG, CO 80111 | Oil & Gas Operator | Feb 2024 |
| 232 | Enduro Operating LLC | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2018 |
| 233 | Enercap Corporation | Kingwood, TX 77325 | Oil & Gas Operator | Aug 2003 |
| 234 | Enercorp Resources, Inc. | Houston, TX 77027 | Oil & Gas Operator | Dec 1993 |
| 235 | Enerex Supply, Inc. | Pampa, TX 79066 | Oil & Gas Operator | Nov 1993 |
| 236 | Enerfin Field Services LLC | Houston, TX 77077 | Oil Operator | Dec 2023 |
| 237 | Enerfin Resources II-92 L.P. | Houston, TX 77077 | Oil & Gas Operator | May 2024 |
| 238 | Energen Resources Corporation | Midland, TX 79701 | Oil & Gas Operator | Jan 2021 |
| 239 | Energen Resources Maq Inc | Birmingham, AL 35203 | Oil & Gas Operator | Sep 2000 |
| 240 | Energetics Inc | Englewood, CO 80155 | Oil & Gas Operator | Aug 1985 |
| 241 | Energex Corp | Springfield, MO 65807 | Oil & Gas Operator | Jan 2024 |
| 242 | Energex Inc. | Abilene, TX 79604 | Oil & Gas Operator | May 2024 |
| 243 | Energon Oil & Gas Inc. | Odessa, TX 79762 | Oil & Gas Operator | Aug 2003 |
| 244 | Energon Oil, Inc. | Amarillo, TX 79114 | Oil & Gas Operator | May 2024 |
| 245 | Energon3 | Rowlett, TX 75089 | Oil Operator | May 2024 |
| 246 | Energy & Expl. PRTNRS Oper., LP | Fort Worth, TX 76147 | Oil & Gas Operator | Oct 2016 |
| 247 | Energy + Savings, L.L.C. | Alamo, TX 78516 | Oil & Gas Operator | Jan 2008 |
| 248 | Energy 2000, Inc. | Reno, NV 89501 | Oil & Gas Operator | May 2024 |
| 249 | Energy Acquisitions, Inc. | Spring, TX 77379 | Oil & Gas Operator | Apr 1996 |
| 250 | Energy Aggregation Services, LLC | Dallas, TX 75367 | Gas Operator | Oct 2022 |
| 251 | Energy Corporation Of America | Charleston, WV 25311 | Oil & Gas Operator | Dec 2022 |
| 252 | Energy Development Corporation | Houston, TX 77067 | Oil & Gas Operator | Dec 2023 |
| 253 | Energy Equity Company | Columbus, MT 59019 | Oil & Gas Operator | Feb 2024 |
| 254 | Energy From Texas, L. P. | Dallas, TX 75230 | Oil & Gas Operator | Dec 2013 |
| 255 | Energy Frontiers Partners, LP | Grapevine, TX 76051 | Oil Operator | May 2008 |
| 256 | Energy Group Of America Inc | Hollister, MO 65672 | Oil Operator | May 2024 |
| 257 | Energy Hunter Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Feb 2019 |
| 258 | Energy Management Company | Kilgore, TX 75663 | Oil Operator | Apr 2020 |
| 259 | Energy Oil & Gas Corporation | Austin, TX 78746 | Oil & Gas Operator | May 2024 |
| 260 | Energy Onramp LLC | Midland, TX 79701 | Oil & Gas Operator | May 2024 |
| 261 | Energy Partners, LTD. | New Orleans, LA 70170 | Oil & Gas Operator | Aug 2012 |
| 262 | Energy Production Corporation | Kilgore, TX 75663 | Oil & Gas Operator | May 2024 |
| 263 | Energy Reserves Group | Houston, TX 770563020 | Oil & Gas Operator | Apr 1996 |
| 264 | Energy Reserves Group LLC | Houston, TX 77002 | Oil & Gas Operator | Mar 2018 |
| 265 | Energy Resource & Develop., Corp | Rockwall, TX 75087 | Oil & Gas Operator | Jun 1998 |
| 266 | Energy Resource Management, Inc. | Caldwell, TX 77836 | Oil & Gas Operator | Mar 2008 |
| 267 | Energy Resource Recovery Corp | Kilgore, TX 75663 | Oil & Gas Operator | May 2024 |
| 268 | Energy Resources Oil & Gas Corp. | Amarillo, TX 79102 | Oil & Gas Operator | Jun 1994 |
| 269 | Energy Search Company Inc | Aurora, CO 80011 | Oil & Gas Operator | Jun 2021 |
| 270 | Energy Service Investment Corp. | Tulsa, OK 74137 | Oil & Gas Operator | May 2006 |
| 271 | Energy Transfer Fuel, LP | Houston, TX 77002 | Oil & Gas Operator | Apr 2005 |
| 272 | Energypro, Inc. | Magnolia, TX 77354 | Oil & Gas Operator | May 2024 |
| 273 | Energyquest II, LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Jan 2024 |
| 274 | Energyquest Management, LLC | Houston, TX 77090 | Oil & Gas Operator | Apr 2021 |
| 275 | Enerquest Corporation | Kilgore, TX 75663 | Oil & Gas Operator | May 2024 |
| 276 | Enerquest Oil & Gas LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | Feb 2024 |
| 277 | Enerquest Operating, LLC | Oklahoma City, OK 73114 | Oil & Gas Operator | May 2024 |
| 278 | Enerquest Resources, LLC | Midland, TX 79702 | Oil & Gas Operator | Nov 2005 |
| 279 | Enerstar Resources, L.C. | Midland, TX 79701 | Oil & Gas Operator | Apr 1999 |
| 280 | Enertex, Inc. | Midland, TX 79702 | Oil & Gas Operator | Aug 1995 |
| 281 | Enervest Operating LLC | Houston, TX 77002 | Oil & Gas Operator | May 2024 |
| 282 | Enex Resources Corporation | Houston, TX 77002 | Oil & Gas Operator | Dec 2009 |
| 283 | Enexco, Inc. | Dallas, TX 75243 | Oil & Gas Operator | Mar 2017 |
| 284 | Enfield Operating Company, LLC | Coppell, TX 75019 | Oil Operator | May 2024 |
| 285 | Eng, George E. | Midland, TX 79701 | Oil & Gas Operator | Dec 2011 |
| 286 | Engas Corporation | Jacksboro, TX 76458 | Oil & Gas Operator | May 2008 |
| 287 | Engas XP, LLC | Wimberley, TX 78676 | Oil & Gas Operator | May 2024 |
| 288 | Engelke, R. H. | San Antonio, TX 78230 | Oil & Gas Operator | May 2024 |
| 289 | Engroup Resources, L.P. | Houston, TX 77002 | Oil & Gas Operator | May 2024 |
| 290 | Enhanced Energy Partners Corp | Tomball, TX 77377 | Oil & Gas Operator | May 2024 |
| 291 | Enhanced RS, Inc. | Luling, TX 78648 | Oil Operator | May 2024 |
| 292 | Enid Operating, Inc. | Pampa, TX 79065 | Oil & Gas Operator | May 2024 |
| 293 | Enline Operating, L.L.C. | Houston, TX 77019 | Oil & Gas Operator | Jun 1998 |
| 294 | Enline Resources, LLC | Houston, TX 77254 | Oil & Gas Operator | Feb 1996 |
| 295 | Enlink Crude Marketing LLC | Dallas, TX 75201 | Oil & Gas Operator | Aug 2022 |
| 296 | Enlo Energy Co., LTD. | Fort Worth, TX 76102 | Oil & Gas Operator | Dec 2001 |
| 297 | Enloe Oil Company | Olney, TX 76374 | Oil & Gas Operator | Jun 2000 |
| 298 | Enmark Gas Gathering L. P. | Dallas, TX 75252 | Oil & Gas Operator | Dec 2023 |
| 299 | Enpower Resources Inc. | Sugar Land, TX 77479 | Oil & Gas Operator | May 2024 |
| 300 | Enr Operating, LLC | Eunice, NM 88231 | Oil & Gas Operator | May 2024 |