| 401 | ULSH 'A' | Grant County, KS | Gas Property | Mar 2025 |
| 402 | ULT 1 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 403 | ULT 3 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 404 | ULT 4 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 405 | ULT 5 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 406 | ULT 6 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 407 | ULT 7 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 408 | ULT 8 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 409 | ULT 9 | Uintah County, UT | Oil & Gas Property | May 2025 |
| 410 | ULTIMATE WARRIOR | Lycoming County, PA | Gas Property | May 2025 |
| 411 | ULTRA U A STATE | Chaves County, NM | Oil & Gas Property | May 2025 |
| 412 | ULURU 35 FEDERAL | Eddy County, NM | Oil & Gas Property | May 2025 |
| 413 | ULVESTAD | Midland County, TX | Oil & Gas Property | Apr 2025 |
| 414 | ULVESTAD-BIRKHEAD E20 | Midland County, TX | Oil & Gas Property | Apr 2025 |
| 415 | UMA UNIT | Hill County, TX | Oil & Gas Property | Apr 2025 |
| 416 | UMANSKY | Alfalfa County, OK | Oil & Gas Property | Apr 2025 |
| 417 | UMBACH | Grady County, OK | Oil & Gas Property | Apr 2025 |
| 418 | UMBACH | Grady County, OK | Oil & Gas Property | Apr 2025 |
| 419 | UMBARGER | Neosho County, KS | Oil & Gas Property | Mar 2025 |
| 420 | UMBARGER | Neosho County, KS | Gas Property | Mar 2025 |
| 421 | UMBARGER | Wilson County, KS | Oil & Gas Property | Mar 2025 |
| 422 | UMBARGER | Wilson County, KS | Oil & Gas Property | Jan 2025 |
| 423 | UMBEHR | Riley County, KS | Oil Property | Mar 2025 |
| 424 | UMBER 11-28-16 | Woods County, OK | Oil & Gas Property | Apr 2025 |
| 425 | UMBERSON | Montague County, TX | Oil & Gas Property | Apr 2025 |
| 426 | UMBERT PETRARCA | Indiana County, PA | Gas Property | Dec 2024 |
| 427 | UMBRELLA POINT UNIT | Chambers County, TX | Oil & Gas Property | Jul 2013 |
| 428 | UMBRIEL B | Lavaca County, TX | Oil & Gas Property | Apr 2025 |
| 429 | UMCC 'A' | Meade County, KS | Oil Property | May 2024 |
| 430 | UMIVERSITY BLOCK 46 | Crockett County, TX | Oil & Gas Property | Apr 2025 |
| 431 | UMLANG-LEHMANN UNIT | Lee County, TX | Oil & Gas Property | Apr 2025 |
| 432 | UMMEL | Ness County, KS | Oil Property | Aug 2015 |
| 433 | UMMEL | Ness County, KS | Oil Property | Mar 2025 |
| 434 | UMMEL | Ness County, KS | Oil Property | Oct 2024 |
| 435 | UMMEL | Ness County, KS | Oil Property | Mar 2025 |
| 436 | UMMEL | Ness County, KS | Oil Property | Mar 2025 |
| 437 | UMPHRESS, C.F. ET AL | Howard County, TX | Oil & Gas Property | Mar 2019 |
| 438 | UMSTEAD | Stafford County, KS | Oil Property | Nov 2024 |
| 439 | UMSTED | Ouachita County, AR | Oil & Gas Property | Dec 2024 |
| 440 | UMSTED | Union County, AR | Oil Property | Jan 2025 |
| 441 | UNA FIFE | Creek County, OK | Oil Property | Jun 2024 |
| 442 | UNA HYRAL | Johnson County, TX | Gas Property | Apr 2025 |
| 443 | UNA PALMER 14 H | De Soto Parish, LA | Gas Property | Dec 2024 |
| 444 | UNBRIDLED 36 | Culberson County, TX | Oil & Gas Property | Apr 2025 |
| 445 | UNBRIDLED 5-8-10-7 | Canadian County, OK | Oil & Gas Property | Apr 2025 |
| 446 | UNCLE BILL | Kingfisher County, OK | Oil & Gas Property | Apr 2025 |
| 447 | UNCLE BILL 1 | Lipscomb County, TX | Oil & Gas Property | Apr 2025 |
| 448 | UNCLE CECIL | Terrell County, TX | Oil & Gas Property | Apr 2025 |
| 449 | UNCLE CHES 21 16 FEDERAL COM | Lea County, NM | Oil & Gas Property | May 2025 |
| 450 | UNCLE CHES 21 16 FEDERAL COM 125H | Lea County, NM | Oil & Gas Property | May 2025 |
| 451 | UNCLE JERRY DAVIS | Liberty County, TX | Oil Property | Mar 2025 |
| 452 | UNCLE RICHARD STATE COM | Lea County, NM | Oil & Gas Property | May 2025 |
| 453 | UNCLE SAM | Lea County, NM | Oil & Gas Property | May 2025 |
| 454 | UNCLE SAM 13 | Lea County, NM | Oil & Gas Property | May 2022 |
| 455 | UNCOMPAGHRE STATE UNIT | Reeves County, TX | Oil & Gas Property | Apr 2025 |
| 456 | UNDAUNTED BSD STATE COM | Lea County, NM | Oil & Gas Property | May 2025 |
| 457 | UNDER THE BRIDGE 452 | Yoakum County, TX | Oil & Gas Property | Apr 2025 |
| 458 | UNDERDAHL | Pondera County, MT | Gas Property | May 2018 |
| 459 | UNDERHILL | Weld County, CO | Oil & Gas Property | May 2025 |
| 460 | UNDERHILL | Marshall County, OK | Oil Property | Aug 2024 |
| 461 | UNDERHILL COAL | Clearfield County, PA | Gas Property | Dec 2023 |
| 462 | UNDERWOOD | Harrison County, TX | Oil & Gas Property | Apr 2025 |
| 463 | UNDERWOOD | Andrews County, TX | Oil & Gas Property | Apr 2025 |
| 464 | UNDERWOOD | Tyler County, WV | Oil & Gas Property | Dec 2021 |
| 465 | UNDERWOOD | Kearny County, KS | Gas Property | Mar 2025 |
| 466 | UNDERWOOD | Caddo Parish, LA | Oil Property | Jan 2025 |
| 467 | UNDERWOOD | McLean County, KY | Oil Property | Aug 2017 |
| 468 | UNDERWOOD | Milam County, TX | Oil & Gas Property | Apr 2025 |
| 469 | UNDERWOOD | Red River County, TX | Oil & Gas Property | Apr 2025 |
| 470 | UNDERWOOD | Crawford County, KS | Oil Property | Aug 2020 |
| 471 | UNDERWOOD | Greenwood County, KS | Oil Property | Mar 2025 |
| 472 | UNDERWOOD | Beaver County, OK | Oil & Gas Property | Oct 2018 |
| 473 | UNDERWOOD | Barton County, KS | Oil Property | Mar 2025 |
| 474 | UNDERWOOD | Ward County, TX | Oil & Gas Property | Apr 2025 |
| 475 | UNDERWOOD | Beaver County, OK | Gas Property | Jan 2024 |
| 476 | UNDERWOOD | Chautauqua County, KS | Oil Property | Feb 2025 |
| 477 | UNDERWOOD | Campbell County, WY | Oil & Gas Property | Aug 2005 |
| 478 | UNDERWOOD | Stark County, OH | Oil & Gas Property | Dec 2024 |
| 479 | UNDERWOOD | Coshocton County, OH | Oil & Gas Property | Dec 2023 |
| 480 | UNDERWOOD | Howard County, TX | Oil & Gas Property | Mar 2025 |
| 481 | UNDERWOOD | Doddridge County, WV | Oil & Gas Property | Dec 2021 |
| 482 | UNDERWOOD | Winkler County, TX | Oil & Gas Property | Apr 2025 |
| 483 | UNDERWOOD | Doddridge County, WV | Oil & Gas Property | Oct 2021 |
| 484 | UNDERWOOD | Faulkner County, AR | Gas Property | Jul 2024 |
| 485 | UNDERWOOD | Haskell County, OK | Gas Property | Apr 2025 |
| 486 | UNDERWOOD | Perry County, OH | Oil & Gas Property | Dec 2024 |
| 487 | UNDERWOOD 33-7-15 | La Plata County, CO | Gas Property | May 2025 |
| 488 | UNDERWOOD A | Seward County, KS | Oil & Gas Property | Mar 2025 |
| 489 | UNDERWOOD MARY E | Montague County, TX | Oil & Gas Property | Feb 2025 |
| 490 | UNDERWOOD, CHARLES G | Doddridge County, WV | Gas Property | Dec 2021 |
| 491 | UNDERWOOD, RALPH | Tyler County, WV | Gas Property | Dec 2021 |
| 492 | UNDERWOOD, RAYMOND | Tyler County, WV | Oil & Gas Property | Dec 2021 |
| 493 | UNDERWOOD, RICHARD M | Wetzel County, WV | Oil & Gas Property | Dec 2021 |
| 494 | UNDERWOOD-BREEN | Denton County, TX | Oil & Gas Property | Apr 2025 |
| 495 | UNDERWOOD-JOHNSON 1 | Hutchinson County, TX | Oil & Gas Property | Apr 2025 |
| 496 | UNDHJEM 1 | Burke County, ND | Oil & Gas Property | May 2025 |
| 497 | UNDINE | Andrews County, TX | Oil & Gas Property | Apr 2025 |
| 498 | UNEY 24-1 | Stanton County, KS | Oil & Gas Property | May 2005 |
| 499 | UNFORGIVEN 34 113-114 | Ward County, TX | Oil & Gas Property | Apr 2025 |
| 500 | UNGER | Armstrong County, PA | Gas Property | Dec 2024 |