| 11501 | Twins Oil Co. | Monahans, TX 79756 | Oil & Gas Operator | Apr 2026 |
| 11502 | Two Bit Operating Company LLC | Fort Worth, TX 76110 | Oil & Gas Operator | Apr 2026 |
| 11503 | Two Black Bears Oil, Inc. | Midland, TX 79710 | Oil & Gas Operator | Sep 2003 |
| 11504 | Two Oaks Operating Company, LLC. | Flower Mound, TX 75028 | Oil & Gas Operator | Mar 2008 |
| 11505 | Two P Partners, LLC | Houston, TX 77056 | Oil & Gas Operator | Apr 2026 |
| 11506 | Twojo, Inc. | Longview, TX 75601 | Oil & Gas Operator | Nov 1996 |
| 11507 | TWS Oil And Gas LLC | Arlington, TX 76006 | Oil Operator | Apr 2026 |
| 11508 | TX Heat Of The Permian Basin Inc | Odessa, TX 79768 | Oil & Gas Operator | Dec 2021 |
| 11509 | TX Lone Star Operating Co, LLC | Sulphur SPGS, TX 75483 | Oil & Gas Operator | Apr 2026 |
| 11510 | TX Petroleum Company | Corpus Christ, TX 78412 | Oil & Gas Operator | Apr 1996 |
| 11511 | Txco Resources Inc. | San Antonio, TX 78280 | Oil & Gas Operator | Apr 2026 |
| 11512 | Txla Energy, Inc. | Houston, TX 77018 | Oil & Gas Operator | Apr 2026 |
| 11513 | Txo Production Corp. | Ganado, TX 77962 | Oil & Gas Operator | Aug 2022 |
| 11514 | Txok Texas Energy Resources,L.P. | Dallas, TX 75251 | Oil & Gas Operator | Apr 2008 |
| 11515 | Txon Partners, LLC | Houston, TX 77057 | Oil & Gas Operator | Jun 2017 |
| 11516 | TXP, Incorporated | San Angelo, TX 76906 | Oil & Gas Operator | Apr 2026 |
| 11517 | Txu Fuel Company | Dallas, TX 75201 | Oil & Gas Operator | May 2004 |
| 11518 | Txu Gas Company | Dallas, TX 75201 | Oil & Gas Operator | Sep 2004 |
| 11519 | Txu Lone Star Pipeline | Dallas, TX 75201 | Oil & Gas Operator | Oct 2003 |
| 11520 | TXX Operating LLC | Shreveport, LA 71133 | Oil & Gas Operator | Apr 2026 |
| 11521 | Ty-Tex Exploration, Inc. | Tyler, TX 75711 | Oil Operator | Dec 2000 |
| 11522 | Tyco Operating Co. | Archer City, TX 76351 | Oil & Gas Operator | Apr 2026 |
| 11523 | Tyl Oil | Canon City, CO 81212 | Gas Operator | May 1994 |
| 11524 | Tyler Oil & Gas Inc. | Tyler, TX 75702 | Oil & Gas Operator | Sep 2004 |
| 11525 | Tyner Texas Operating Company | Dallas, TX 75248 | Oil & Gas Operator | Apr 2026 |
| 11526 | U S Energy Corp. Of Amer. Inc. | Cisco, TX 76437 | Oil & Gas Operator | Apr 2026 |
| 11527 | U. D. Man, Inc. | San Antonio, TX 78212 | Oil & Gas Operator | Apr 2026 |
| 11528 | U. S. Energy Development Corporation | Fort Worth, TX 76164 | Oil & Gas Operator | Apr 2026 |
| 11529 | U. S. Operating, Inc. | Dallas, TX 75252 | Oil & Gas Operator | Jul 2025 |
| 11530 | U.S. Enercorp, LLC | San Antonio, TX 78217 | Oil & Gas Operator | Jul 2004 |
| 11531 | U.S. Enercorp, LTD. | San Antonio, TX 78209 | Oil & Gas Operator | Sep 2019 |
| 11532 | U.S. Exploration Company | Houston, TX 77002 | Oil & Gas Operator | Aug 2003 |
| 11533 | U.S. Sovereign Oil And Gas, Inc. | Dallas, TX 75355 | Oil & Gas Operator | Apr 2026 |
| 11534 | U.S.A. Plugging Company | Pearsall, TX 78061 | Oil & Gas Operator | Apr 2026 |
| 11535 | U1 Ranch Oil | Houston, TX 77269 | Oil & Gas Operator | Apr 2026 |
| 11536 | Ubetco, Inc. | Rockdale, TX 76567 | Oil & Gas Operator | Apr 2026 |
| 11537 | Uhc Petroleum Corporation | Rocksprings, TX 78880 | Oil & Gas Operator | Apr 2026 |
| 11538 | Ulatex Oil & Gas Inc. | Nocona, TX 76255 | Oil & Gas Operator | Dec 1998 |
| 11539 | Ultra Oil & Gas, Inc. | Centerton, AR 72719 | Oil & Gas Operator | Apr 2026 |
| 11540 | Ultra Petroleum (U.S.A.), Inc. | Granbury, TX 76048 | Oil & Gas Operator | Sep 2003 |
| 11541 | Ultra Resources Inc | Houston, TX 77060 | Oil & Gas Operator | Sep 2018 |
| 11542 | Umc Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Mar 2015 |
| 11543 | Umma Resources, LLC | Portland, TX 78374 | Gas Operator | Apr 2026 |
| 11544 | Unbridled Resources, LLC | Oklahoma City, OK 73102 | Oil & Gas Operator | Apr 2026 |
| 11545 | Underwood, Jim | Graham, TX 76450 | Oil & Gas Operator | Mar 2018 |
| 11546 | Unicorn Energy, Inc. | Elgin, TX 78621 | Oil & Gas Operator | Apr 2026 |
| 11547 | Unified Oil & Gas Corp. | Snyder, TX 79550 | Oil Operator | Apr 2026 |
| 11548 | Union Crude Company | Baytown, TX 77521 | Oil & Gas Operator | Apr 2018 |
| 11549 | Union Crude Operating Co. | Baytown, TX 77521 | Oil Operator | Aug 2003 |
| 11550 | Union Gas Operating Company | Spring, TX 77391 | Oil & Gas Operator | Apr 2026 |
| 11551 | Union Oil Co Of California | Midland, TX 79706 | Oil & Gas Operator | Jan 2022 |
| 11552 | Union Pacific Austin Chalk Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 11553 | Union Pacific Resources Co. | Fort Worth, TX 76101 | Oil & Gas Operator | Jan 2001 |
| 11554 | Union Royalty, Inc. | Midland, TX 79706 | Oil & Gas Operator | Jul 2014 |
| 11555 | Union Seaboard Corporation | Houston, TX 77024 | Oil & Gas Operator | Mar 2008 |
| 11556 | Unit Petroleum Company | Tulsa, OK 74170 | Oil & Gas Operator | Apr 2026 |
| 11557 | United Company | Lubbock, TX 79408 | Oil & Gas Operator | Jun 1995 |
| 11558 | United Energy Corporation | San Antonio, TX 78209 | Oil & Gas Operator | Apr 2026 |
| 11559 | United Energy Operating, LLC | Edmond, OK 73083 | Oil & Gas Operator | Apr 2026 |
| 11560 | United Energy Partners, Inc. | Dallas, TX 75201 | Oil & Gas Operator | Mar 2008 |
| 11561 | United Oil & Minerals L. P. | Austin, TX 78746 | Oil & Gas Operator | Jun 2003 |
| 11562 | United Oil & Minerals, Inc. | Austin, TX 78746 | Oil & Gas Operator | Jan 2001 |
| 11563 | United Oil & Shale LLC | Woodward, OK 73801 | Oil & Gas Operator | Apr 2026 |
| 11564 | United Operating Company | Olney, TX 76374 | Oil & Gas Operator | Aug 2003 |
| 11565 | United Operating, LLC *** | Midland, TX 79710 | Oil & Gas Operator | Apr 2026 |
| 11566 | United Petroleum & Gas, Inc. | Kilgore, TX 75663 | Oil & Gas Operator | Apr 2026 |
| 11567 | United Petroleum Technologies | Hondo, TX 78861 | Oil & Gas Operator | Aug 2001 |
| 11568 | United Resources LP | Austin, TX 78746 | Oil & Gas Operator | Oct 2011 |
| 11569 | United States Gypsum Company | Oakfield, NY 14125 | Oil & Gas Operator | Dec 2024 |
| 11570 | United Texas Oil LLC | Houston, TX 77027 | Oil & Gas Operator | Apr 2026 |
| 11571 | United Texas Petroleum Inc. | McKinney, TX 75070 | Oil & Gas Operator | Apr 2026 |
| 11572 | United World Energy, Inc. | Aurora, CO 80040 | Oil & Gas Operator | Apr 2026 |
| 11573 | Unitex Oil & Gas, L.L.C. | Midland, TX 79701 | Oil & Gas Operator | Apr 2026 |
| 11574 | Universal Geopower LLC | Houston, TX 77057 | Oil & Gas Operator | May 2016 |
| 11575 | Universal Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Sep 2002 |
| 11576 | Universal Resources Corp. | Salt Lake Cty, UT 84145 | Oil & Gas Operator | Jan 2000 |
| 11577 | Unknown | Houston, TX 77208 | Oil & Gas Operator | Dec 2024 |
| 11578 | Unocal Exploration Corporation | Houston, TX 77001 | Oil & Gas Operator | May 1992 |
| 11579 | Unoco, Inc. | Kerrville, TX 78029 | Oil & Gas Operator | Jan 1999 |
| 11580 | Unoso Operating Company L.L.C. | Georgetown, TX 78633 | Oil & Gas Operator | Apr 2026 |
| 11581 | Unswept Oil Company | Corsicana, TX 75151 | Oil & Gas Operator | Jan 2018 |
| 11582 | Untamed Resources, LLC | Spearman, TX 79081 | Gas Operator | Apr 2026 |
| 11583 | Uosi Operating, Inc. | Lovelady, TX 75851 | Oil & Gas Operator | Apr 2026 |
| 11584 | Upcurve Energy, LLC | Houston, TX 77024 | Oil & Gas Operator | Apr 2026 |
| 11585 | Upda Operators, Inc. | Jacksboro, TX 76458 | Oil & Gas Operator | Dec 2009 |
| 11586 | Upham Oil & Gas Company | Mineral Wells, TX 76068 | Oil & Gas Operator | Apr 2026 |
| 11587 | Upham, Chester R., Jr. | Mineral Wells, TX 76067 | Oil & Gas Operator | Aug 2001 |
| 11588 | Uphill Consulting LLC | Pearland, TX 77584 | Oil & Gas Operator | Apr 2026 |
| 11589 | Upland Exploration, LLC | Boerne, TX 78006 | Oil & Gas Operator | Jul 2024 |
| 11590 | Upland Operating, LLC | Dallas, TX 75226 | Oil & Gas Operator | Apr 2026 |
| 11591 | Upland Production Company | Edmond, OK 73083 | Oil & Gas Operator | Apr 2026 |
| 11592 | Upland Resources LLC | Canadian, TX 79014 | Oil & Gas Operator | Apr 2026 |
| 11593 | Upland Resources, Inc. | Canadian, TX 79014 | Oil & Gas Operator | Dec 2009 |
| 11594 | Uplands Resources Inc | Tulsa, OK 74103-4141 | Oil & Gas Operator | Feb 2026 |
| 11595 | Uplift Production Company, Inc. | Shamrock, TX 79079 | Oil & Gas Operator | Feb 1999 |
| 11596 | Upp Operating, LLC | Houston, TX 77002 | Oil & Gas Operator | Apr 2026 |
| 11597 | Upstream Exploration LLC | Metairie, LA 70002 | Oil & Gas Operator | Jan 2020 |
| 11598 | Upstream Properties, LLC | Southlake, TX 76092 | Oil & Gas Operator | Apr 2026 |
| 11599 | Upstream Resource Partners, LLC | Elkhart, TX 75839 | Oil Operator | Apr 2026 |
| 11600 | Uptex Operating Inc. | Dallas, TX 75201 | Oil & Gas Operator | May 2011 |