| 11401 | Txok Texas Energy Resources,L.P. | Dallas, TX 75251 | Oil & Gas Operator | Apr 2008 |
| 11402 | Txon Partners, LLC | Houston, TX 77057 | Oil & Gas Operator | Jun 2017 |
| 11403 | TXP, Incorporated | San Angelo, TX 76906 | Oil & Gas Operator | Dec 2024 |
| 11404 | Txu Fuel Company | Dallas, TX 75201 | Oil & Gas Operator | May 2004 |
| 11405 | Txu Gas Company | Dallas, TX 75201 | Oil & Gas Operator | Sep 2004 |
| 11406 | Txu Lone Star Pipeline | Dallas, TX 75201 | Oil & Gas Operator | Oct 2003 |
| 11407 | TXX Operating LLC | Shreveport, LA 71133 | Oil & Gas Operator | Dec 2024 |
| 11408 | Ty-Tex Exploration, Inc. | Tyler, TX 75711 | Oil Operator | Dec 2000 |
| 11409 | Tyco Operating Co. | Archer City, TX 76351 | Oil & Gas Operator | Dec 2024 |
| 11410 | Tyl Oil | Canon City, CO 81212 | Gas Operator | May 1994 |
| 11411 | Tyler Oil & Gas Inc. | Tyler, TX 75702 | Oil & Gas Operator | Sep 2004 |
| 11412 | Tyner Texas Operating Company | Dallas, TX 75248 | Oil & Gas Operator | Dec 2024 |
| 11413 | U S Energy Corp. Of Amer. Inc. | Ranger, TX 76470 | Oil & Gas Operator | Dec 2024 |
| 11414 | U. D. Man, Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Dec 2024 |
| 11415 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Dec 2024 |
| 11416 | U.S. Enercorp, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2004 |
| 11417 | U.S. Enercorp, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2019 |
| 11418 | U.S. Energy Development Corp | Arlington, TX 76011 | Oil & Gas Operator | Dec 2024 |
| 11419 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 11420 | U.S. Sovereign Oil And Gas, Inc. | Dallas, TX 75355 | Oil & Gas Operator | Dec 2024 |
| 11421 | U.S.A. Plugging Company | Pearsall, TX 78061 | Oil & Gas Operator | Dec 2024 |
| 11422 | U1 Ranch Oil | Houston, TX 77269 | Oil & Gas Operator | Dec 2024 |
| 11423 | Ubetco, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Dec 2024 |
| 11424 | Uhc Petroleum Corporation | Rocksprings, TX 78880 | Oil & Gas Operator | Dec 2024 |
| 11425 | Ulatex Oil & Gas Inc. | Nocona, TX 76255 | Oil & Gas Operator | Dec 1998 |
| 11426 | Ultra Oil & Gas, Inc. | Centerton, AR 72719 | Oil & Gas Operator | Dec 2024 |
| 11427 | Ultra Petroleum (U.S.A.), Inc. | Granbury, TX 76048 | Oil & Gas Operator | Sep 2003 |
| 11428 | Ultra Resources Inc | Houston, TX 77060 | Oil & Gas Operator | Sep 2018 |
| 11429 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 11430 | Umma Resources, LLC | Portland, TX 78374 | Gas Operator | Dec 2024 |
| 11431 | Unbridled Resources, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 11432 | Underwood, Jim | Graham, TX 76450 | Oil & Gas Operator | Mar 2018 |
| 11433 | Unicorn Energy, Inc. | Elgin, TX 78621 | Oil & Gas Operator | Dec 2024 |
| 11434 | Unified Oil & Gas Corp. | Snyder, TX 79550 | Oil Operator | Dec 2024 |
| 11435 | Union Crude Company | Baytown, TX 77521 | Oil & Gas Operator | Apr 2018 |
| 11436 | Union Crude Operating Co. | Baytown, TX 77521 | Oil Operator | Aug 2003 |
| 11437 | Union Gas Operating Company | Houston, TX 77014 | Oil & Gas Operator | Dec 2024 |
| 11438 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 11439 | Union Pacific Austin Chalk Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 11440 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Sep 2002 |
| 11441 | Union Royalty, Inc. | Midland, TX 79706 | Oil & Gas Operator | Jul 2014 |
| 11442 | Union Seaboard Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 11443 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Dec 2024 |
| 11444 | United Company | Lubbock, TX 79408 | Oil & Gas Operator | Jun 1995 |
| 11445 | United Energy Corporation | San Antonio, TX 78209 | Oil & Gas Operator | Dec 2024 |
| 11446 | United Energy Operating, LLC | Edmond, OK 73083 | Oil & Gas Operator | Dec 2024 |
| 11447 | United Energy Partners, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2008 |
| 11448 | United Energy Trading LLC | Tulsa, OK 74133 | Gas Operator | Feb 2015 |
| 11449 | United Oil & Minerals L. P. | Austin, TX 78746 | Oil & Gas Operator | Jun 2003 |
| 11450 | United Oil & Minerals, Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2001 |
| 11451 | United Operating Co. | Olney, TX 76374 | Oil & Gas Operator | Aug 2003 |
| 11452 | United Operating, LLC *** | Midland, TX 79710 | Oil & Gas Operator | Dec 2024 |
| 11453 | United Petroleum & Gas, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Dec 2024 |
| 11454 | United Petroleum Technologies | Hondo, TX 78861 | Oil & Gas Operator | Aug 2001 |
| 11455 | United Resources LP | Austin, TX 78746 | Oil & Gas Operator | Oct 2011 |
| 11456 | United States Gypsum Co | Oakfield, NY 14125 | Oil & Gas Operator | Dec 2023 |
| 11457 | United Texas Oil LLC | Houston, TX 77027 | Oil & Gas Operator | Dec 2024 |
| 11458 | United Texas Petroleum Inc. | McKinney, TX 75070 | Oil & Gas Operator | Dec 2024 |
| 11459 | United World Energy, Inc. | Aurora, CO 80040 | Oil & Gas Operator | Dec 2024 |
| 11460 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Dec 2024 |
| 11461 | Universal Geopower LLC | Houston, TX 77057 | Oil & Gas Operator | May 2016 |
| 11462 | Universal Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2002 |
| 11463 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 11464 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2022 |
| 11465 | Unoso Operating Company L.L.C. | Georgetown, TX 78633 | Oil & Gas Operator | Dec 2024 |
| 11466 | Unswept Oil Company | Corsicana, TX 75151 | Oil & Gas Operator | Jan 2018 |
| 11467 | Untamed Resources, LLC | Spearman, TX 79081 | Gas Operator | Dec 2024 |
| 11468 | Uosi Operating, Inc. | Lovelady, TX 75851 | Oil & Gas Operator | Dec 2024 |
| 11469 | Upcurve Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Dec 2024 |
| 11470 | Upda Operators, Inc. | Jacksboro, TX 76458 | Oil & Gas Operator | Dec 2009 |
| 11471 | Upham Oil & Gas Company | Mineral Wells, TX 76068 | Oil & Gas Operator | Dec 2024 |
| 11472 | Upham, Chester R., Jr. | Mineral Wells, TX 76067 | Oil & Gas Operator | Aug 2001 |
| 11473 | Uphill Consulting LLC | Pearland, TX 77584 | Oil Operator | Dec 2024 |
| 11474 | Upland Exploration, LLC | Boerne, TX 78006 | Oil & Gas Operator | Jul 2024 |
| 11475 | Upland Operating, LLC | Dallas, TX 75226 | Oil & Gas Operator | Dec 2024 |
| 11476 | Upland Production Company | Edmond, OK 73083 | Oil & Gas Operator | Dec 2024 |
| 11477 | Upland Resources LLC | Canadian, TX 79014 | Oil & Gas Operator | Dec 2024 |
| 11478 | Upland Resources, Inc. | Canadian, TX 79014 | Oil & Gas Operator | Dec 2009 |
| 11479 | Uplands Resources Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Sep 2024 |
| 11480 | Uplift Production Company, Inc. | Shamrock, TX 79079 | Oil & Gas Operator | Feb 1999 |
| 11481 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 11482 | Upstream Exploration LLC | Metairie, LA 70002 | Oil & Gas Operator | Jan 2020 |
| 11483 | Upstream Properties, LLC | Southlake, TX 76092 | Oil & Gas Operator | Dec 2024 |
| 11484 | Upstream Resource Partners, LLC | Palestine, TX 75803 | Oil Operator | Dec 2024 |
| 11485 | Uptex Operating Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2011 |
| 11486 | Uptex Operating, L.P. | Dallas, TX 75201 | Oil & Gas Operator | May 2010 |
| 11487 | Urban Oil & Gas Group, LLC | Plano, TX 75074 | Oil & Gas Operator | Dec 2024 |
| 11488 | Ursa Operating Company LLC | Denver, CO 80265 | Oil & Gas Operator | Dec 2020 |
| 11489 | Ursus Oil And Gas | Tyler, TX 75703 | Oil & Gas Operator | Dec 2024 |
| 11490 | Us Ecology Winnie, LLC | Winnie, TX 77665 | Oil Operator | Dec 2024 |
| 11491 | Us Energy Corp. | Houston, TX 77057 | Oil & Gas Operator | Dec 2021 |
| 11492 | Us Energy Holdings, LLC | Richardson, TX 75080 | Oil & Gas Operator | Dec 2024 |
| 11493 | Us Petro LP | Amarillo, TX 79106 | Oil & Gas Operator | Apr 2020 |
| 11494 | Us. Fuels, Inc. | Breckenridge, TX 76424 | Oil & Gas Operator | Dec 2024 |
| 11495 | USA Superior Energy LLC | Houston, TX 77077 | Oil Operator | Mar 2010 |
| 11496 | USA Tubulars, Inc. | Valley Spring, TX 76885 | Oil & Gas Operator | Dec 1995 |
| 11497 | Usfg Oil & Gas, Inc. | Dallas, TX 75231 | Oil & Gas Operator | Dec 2005 |
| 11498 | Utility Ventures Company | Pasadena, TX 77504 | Oil & Gas Operator | Dec 2024 |
| 11499 | Utoco, LTD. | Midland, TX 79704 | Oil Operator | Dec 2024 |
| 11500 | Uvalde Energy Co. | Austin, TX 78747 | Oil & Gas Operator | Nov 1994 |