| 301 | Enloe Oil Company | Olney, TX 76374 | Oil & Gas Operator | Jun 2000 |
| 302 | Enmark Gas Gathering LP | Dallas, TX 75252 | Oil & Gas Operator | Dec 2025 |
| 303 | Enpower Resources Inc. | Sugar Land, TX 77479 | Oil & Gas Operator | Apr 2026 |
| 304 | Enr Operating, LLC | Eunice, NM 88231 | Oil & Gas Operator | Apr 2026 |
| 305 | Enre Corp. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2005 |
| 306 | Enre LP | Kingwood, TX 77339 | Oil & Gas Operator | Feb 2004 |
| 307 | Enrich Oil Corporation | Abilene, TX 79604 | Oil & Gas Operator | Apr 2026 |
| 308 | Enron Oil & Gas Company | Houston, TX 77210 | Oil & Gas Operator | Dec 1999 |
| 309 | Enserch Exploration Inc | Dallas, TX 75206 | Oil & Gas Operator | Apr 2015 |
| 310 | Enserch Oil & Gas, Inc. | Dallas, TX 75206 | Oil & Gas Operator | Mar 1998 |
| 311 | Ensight Energy Management, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Jul 2005 |
| 312 | Ensight III Energy MGMT, LLC | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2008 |
| 313 | Ensight IV Energy Management,LLC | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2024 |
| 314 | Ensight Resources, L.L.C. | Shreveport, LA 71101 | Oil & Gas Operator | Apr 2001 |
| 315 | Ensign Operating Co. | Denver, CO 80202 | Oil & Gas Operator | Jan 2004 |
| 316 | Ensign Operating LLC | Houston, TX 77086 | Oil & Gas Operator | Feb 2023 |
| 317 | Enstar Energy, Inc. | Arlington, TX 76003 | Oil & Gas Operator | Apr 2026 |
| 318 | Enterra Resources, LLC | Edmond, OK 73083 | Oil & Gas Operator | Dec 2025 |
| 319 | Enwest Resources, Inc. | Midland, TX 79705 | Oil & Gas Operator | Aug 1994 |
| 320 | EOG (Oklahoma) Inc. | Oklahoma City, OK 73112 | Oil & Gas Operator | Oct 2016 |
| 321 | EOG Resources Inc | Midland, TX 79702 | Oil & Gas Operator | Apr 2026 |
| 322 | Eor Operating Company | Houston, TX 77079 | Oil & Gas Operator | Apr 2026 |
| 323 | EP Energy E&P Company, LLC | Houston, TX 77024 | Oil & Gas Operator | Apr 2025 |
| 324 | EP Energy E&P Company, LP | Houston, TX 77210 | Oil & Gas Operator | Jan 2023 |
| 325 | EP Operating Limited Partnership | Dallas, TX 75201 | Oil & Gas Operator | Feb 1995 |
| 326 | Epic Permian Operating, LLC | Arvada, CO 80006 | Oil & Gas Operator | Jan 2025 |
| 327 | Epstein, Edwin A Jr Oper Co Inc | Las Vegas, NV 89128 | Gas Operator | Dec 2001 |
| 328 | Eqt Production Texas, LLC | Pittsburgh, PA 15222 | Oil & Gas Operator | Jun 2018 |
| 329 | Eqv Operating LLC | Oklahoma City, OK 73172 | Oil & Gas Operator | Apr 2026 |
| 330 | Eratz Investments Inc. | Dallas, TX 75240 | Oil & Gas Operator | Apr 2026 |
| 331 | Erebor Resources LLC | Tyler, TX 75702 | Oil & Gas Operator | Dec 2025 |
| 332 | Erg Operating Company Inc | Houston, TX 77002 | Oil & Gas Operator | Dec 2006 |
| 333 | Erg Resources LLC | Houston, TX 77002 | Oil & Gas Operator | Oct 2015 |
| 334 | Ergon Energy Partners, L.P. | Jackson, MS 39215 | Oil & Gas Operator | Apr 2024 |
| 335 | Ericksen, W.R. | Hobbs, NM 88240 | Oil & Gas Operator | Nov 1993 |
| 336 | Erin Oil Co. | Midland, TX 79707 | Oil & Gas Operator | Apr 2026 |
| 337 | Erin Oil Exploration, Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Dec 1996 |
| 338 | Ermis Vacuum Service | El Campo, TX 77437 | Oil & Gas Operator | Mar 2010 |
| 339 | Ermis Vacuum Service, LLC | El Campo, TX 77437 | Oil & Gas Operator | Apr 2026 |
| 340 | Ernest Operating Company | Rockdale, TX 76567 | Oil & Gas Operator | Apr 2026 |
| 341 | Ernmar Investments, Inc. | Edmond, OK 73083 | Oil & Gas Operator | Apr 2026 |
| 342 | Eros Operating LLC | The Woodlands, TX 77381 | Oil & Gas Operator | Apr 2026 |
| 343 | Erskine Energy, LLC | H SPG NTL PK, AR 71909 | Oil & Gas Operator | Apr 2026 |
| 344 | Erskine Operating LLC | Houston, TX 77079 | Oil & Gas Operator | Dec 2007 |
| 345 | Erso, Inc. | Houston, TX 77002 | Gas Operator | Mar 1995 |
| 346 | Erson Royalty Company, Inc. | Merkel, TX 79536 | Oil & Gas Operator | Feb 2006 |
| 347 | Erwin Oil Company | Jacksboro, TX 76458 | Oil Operator | Apr 2026 |
| 348 | Erwin Operating | Graham, TX 76450 | Oil & Gas Operator | Apr 2026 |
| 349 | Erwin, James D. | Dallas, TX 75225 | Oil & Gas Operator | Nov 1993 |
| 350 | Esco Oil Operating Company LLC | Houston, TX 77007 | Oil & Gas Operator | Apr 2026 |
| 351 | Escoba Royalty Corporation | San Antonio, TX 78217 | Oil & Gas Operator | Nov 2005 |
| 352 | Escondido Bay Corporation | Dallas, TX 75202 | Oil & Gas Operator | Apr 2026 |
| 353 | Escondido Operating, Inc. | Carrollton, TX 75011 | Oil & Gas Operator | Jun 2013 |
| 354 | Escondido Petroleum Company, Inc | Houston, TX 77063 | Oil & Gas Operator | Apr 2026 |
| 355 | Escondido Resources GP, LLC | Midland, TX 79708 | Oil & Gas Operator | Dec 2007 |
| 356 | Escondido Resources II, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2017 |
| 357 | Escondido Resources Oper Co, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 358 | Escudo Oil & Gas, LLC | Houston, TX 77006 | Oil & Gas Operator | Apr 2026 |
| 359 | Esenjay Exploration, Inc | Houston, TX 77042 | Oil & Gas Operator | Jan 2026 |
| 360 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 361 | Esg Resources LLC | Dallas, TX 75231 | Oil & Gas Operator | Apr 2026 |
| 362 | Esna Operating Co., Inc. | Wichita Falls, TX 76301 | Oil & Gas Operator | Oct 1994 |
| 363 | Esoterra, Inc. | Granbury, TX 76049 | Oil & Gas Operator | Apr 2026 |
| 364 | Esp Energy, LLC | Nocona, TX 76255 | Oil Operator | Apr 2026 |
| 365 | Espada Operating LLC | San Antonio, TX 78209 | Oil Operator | Apr 2026 |
| 366 | Esperanza Energy Corp. | Prosper, TX 75078 | Oil & Gas Operator | Mar 2015 |
| 367 | Essman Energy, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Sep 2019 |
| 368 | Estacado Energy, Inc. | Austin, TX 78716 | Oil & Gas Operator | Jul 1999 |
| 369 | Estacado Energy, LLC | Iowa Park, TX 76367 | Oil & Gas Operator | Apr 2026 |
| 370 | Estancia Oil & Gas, LLC | Austin, TX 78716 | Oil & Gas Operator | Apr 2026 |
| 371 | Estate Of C.B. Christie Jr | Wichita Falls, TX 76308 | Oil & Gas Operator | Apr 2026 |
| 372 | Estate Of James L. Nelson | Pettus, TX 78146 | Oil & Gas Operator | Apr 2026 |
| 373 | Estate Of Troy Davis Williams | Ozona, TX 76943 | Oil Operator | Apr 2026 |
| 374 | Estate Oil & Gas Corp. | Dallas, TX 75206 | Oil & Gas Operator | Oct 2011 |
| 375 | Estes And Company LLC. | Perryton, TX 79070 | Oil & Gas Operator | Apr 2026 |
| 376 | Estes Operating, Inc. | San Antonio, TX 78210 | Oil & Gas Operator | Mar 2002 |
| 377 | Estes Operating, LLC | La Porte, TX 77571 | Oil & Gas Operator | Apr 2026 |
| 378 | Estoril Producing Corporation | Midland, TX 79701 | Oil & Gas Operator | Apr 1994 |
| 379 | Et Gathering & Processing LLC | Dallas, TX 75225 | Oil Operator | Dec 2024 |
| 380 | Etc Field Services LLC | San Antonio, TX 78258 | Oil Operator | Jun 2018 |
| 381 | Etc Oil Co. | Pecos, TX 79772 | Oil & Gas Operator | Mar 2004 |
| 382 | Etc Texas Pipeline, LTD. | Dallas, TX 75225 | Oil Operator | Sep 2023 |
| 383 | Etl Hydrocarbons, Inc. | Andrews, TX 79714 | Oil & Gas Operator | Apr 2026 |
| 384 | Etm Operating Company, Inc. | Houston, TX 77079 | Oil Operator | Feb 2009 |
| 385 | Etoco Incorporated | Houston, TX 77002 | Oil & Gas Operator | May 2005 |
| 386 | Etoco, L.P. | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 387 | Etopsi Oil And Gas, L.L.C. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2026 |
| 388 | Etos Operating, Inc. | New London, TX 75682 | Oil & Gas Operator | Apr 2026 |
| 389 | Ettco Enterprises, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2024 |
| 390 | Etx Energy, LLC | Tulsa, OK 74136 | Oil & Gas Operator | Oct 2022 |
| 391 | Eubank, Robert B. & B. K. | Spring, TX 77388 | Oil & Gas Operator | Mar 2008 |
| 392 | Eureka Gas Co, Inc | Pikeville, KY 41502 | Gas Operator | Dec 2010 |
| 393 | Eureka Prospecting Company | Wimberley, TX 78676 | Oil & Gas Operator | Jun 2023 |
| 394 | European-Southwest Co. | Houston, TX 77254 | Oil & Gas Operator | Apr 2026 |
| 395 | Eurotex Royalty, Inc. | Arlington, TX 76012 | Oil & Gas Operator | Aug 2003 |
| 396 | Eurovest Oil & Gas, Inc. | Graham, TX 76450 | Oil & Gas Operator | Mar 2008 |
| 397 | Ev Fleming Enterprises, LLC | Kilgore, TX 75662 | Oil & Gas Operator | Aug 2024 |
| 398 | Evangeline Trading Company | Ballinger, TX 76821 | Oil & Gas Operator | Apr 2026 |
| 399 | Evans Production Co. | Pampa, TX 79066 | Oil & Gas Operator | Sep 2020 |
| 400 | Evans, Carl N. | Graham, TX 76450 | Oil & Gas Operator | Feb 2001 |