| TXL South Unit O-10-20726 | Formentera Operations LLC only | TXL (Tubb) | Ector | 718 | 21.3M | 42.2M | Jan 1993 – Apr 2026 |
| TXL North Unit O-10-20487 | Formentera Operations LLC only | TXL (Tubb) | Ector | 496 | 13.9M | 40.3M | Jan 1993 – Apr 2026 |
| Goldsmith-Cummins /Deep/ Unit O-10-20543 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 396 | 10.2M | 28.1M | Jan 1993 – Apr 2026 |
| Barrow, Augusta O-10-43701 | Formentera Operations LLC only | Spraberry (Trend Area) | Ector | 37 | 1.79M | 4.32M | Mar 2013 – Apr 2026 |
| Barrow, Augusta O-10-14687 | Formentera Operations LLC only | Cowden, North | Ector | 16 | 1.45M | 69.9K | Jan 1993 – Nov 2025 |
| Laren O-10-2130 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 14 | 1.21M | 2.11M | Jan 1993 – Apr 2026 |
| Cummins, H. E. O-10-11783 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 14 | 871K | 3.9M | Jan 1993 – Apr 2026 |
| Cummins -B- O-10-12239 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 27 | 784K | 1.92M | Jan 1993 – Apr 2026 |
| Ector Fee Unit II O-10-21673 | Formentera Operations LLC only | Harper (Ellenburger) | Ector | 3 | 726K | 733K | Jan 1993 – Apr 2026 |
| Cummins, H. E. -C- O-10-11966 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 12 | 588K | 1.74M | Jan 1996 – Apr 2026 |
| Blue Estate O-10-15745 | Formentera Operations LLC only | Wheeler (Wolfcamp) | Winkler | 11 | 585K | 6.27M | Jan 1993 – Apr 2026 |
| Carlinville National Bank O-10-15281 | Formentera Operations LLC only | Yarbrough & Allen (Devonian) | Ector | 5 | 283K | 396K | Jan 1993 – Apr 2026 |
| TXL O-10-25455 | Formentera Operations LLC only | Cowden, North | Ector | 7 | 256K | 520K | Jan 1993 – Apr 2026 |
| Cummins, H.E. 'K' O-10-37058 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 2 | 221K | 494K | Mar 2003 – Aug 2024 |
| Slator, J. D., Jr. O-10-12795 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 7 | 221K | 501K | Jan 1993 – Apr 2026 |
| Blue, R. H. O-10-15464 | Formentera Operations LLC only | Wheeler (Wolfcamp) | Ector | 4 | 216K | 1.61M | Jan 1993 – Apr 2026 |
| TXL "K" Tract II O-10-24229 | Formentera Operations LLC only | TXL (Ellenburger) | Ector | 1 | 199K | 483K | Jan 1993 – Apr 2026 |
| Cahill, T. G., -B- O-10-13476 | Formentera Operations LLC only | Wheeler (Wolfcamp) | Ector | 2 | 198K | 390K | Jan 1993 – Apr 2026 |
| Cummins, H.e."k" O-10-24278 | Formentera Operations LLC only | Goldsmith, N. (San Andres, Con.) | Ector | 3 | 189K | 482K | Jan 1993 – Dec 2022 |
| Mrs. T. B. Roberts R/a -A- O-10-29630 | Formentera Operations LLC only | Fasken (Penn.) | Ector | 2 | 148K | 1.21M | Jan 1993 – Apr 2026 |
| TXL O-10-846 | Formentera Operations LLC only | Cowden, North (Deep) | Ector | 6 | 141K | 241K | Jan 1993 – Oct 2019 |
| Cummins, H. E. -A- O-10-35910 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 4 | 140K | 651K | May 1998 – Apr 2026 |
| Slator -B- O-10-6972 | Formentera Operations LLC only | TXL (Ellenburger) | Ector | 2 | 130K | 430K | Jan 1993 – Apr 2026 |
| Barrow, Augusta O-10-45396 | Formentera Operations LLC only | Lowe (Atoka) | Ector | 4 | 129K | 340K | Nov 2013 – Apr 2026 |
| Petsch O-10-6961 | Formentera Operations LLC only | TXL (Ellenburger) | Ector | 1 | 125K | 319K | Jan 1993 – Apr 2026 |
| TXL -O- O-10-16856 | Formentera Operations LLC only | TXL (Devonian) | Ector | 1 | 112K | 100K | Jan 1993 – Apr 2026 |
| TXL -E- O-10-15708 | Formentera Operations LLC only | TXL (Devonian) | Ector | 5 | 111K | 766K | Jan 1993 – Dec 2024 |
| Barrow, Augusta O-10-27395 | Formentera Operations LLC only | Hence (Grayburg) | Ector | 3 | 110K | 17.8K | Jan 1993 – Apr 2026 |
| Slator -B- O-10-7004 | Formentera Operations LLC only | TXL (Silurian) | Ector | 1 | 109K | 536K | Jan 1993 – Apr 2026 |
| Ector -E- Fee /NCT-2/ O-10-16998 | Formentera Operations LLC only | Harper | Ector | 6 | 104K | 62.4K | Jan 1993 – Apr 2026 |
| TXL -D- O-10-8248 | Formentera Operations LLC only | Andector, West (Devonian) | Ector | 1 | 103K | 183K | Jan 1993 – Apr 2026 |
| Wheeler, R. A., -F- O-10-15471 | Formentera Operations LLC only | Wheeler (Wolfcamp) | Ector | 2 | 103K | 1.13M | Jan 1993 – Feb 2022 |
| Ector -E- Fee NCT-2 O-10-17723 | Formentera Operations LLC only | Harper (Ellenburger) | Ector | 2 | 100K | 107K | Dec 1996 – Sep 2015 |
| Barrow, Augusta O-10-16516 | Formentera Operations LLC only | Headlee, N. (Devonian) | Ector | 11 | 99.7K | 937K | Jan 1993 – Apr 2026 |
| TXL -G- O-10-16060 | Formentera Operations LLC only | Lawson (San Andres) | Ector | 2 | 97K | 312K | Jan 1993 – Nov 2021 |
| Slator -B- O-10-15546 | Formentera Operations LLC only | TXL (Devonian) | Ector | 3 | 96.9K | 521K | Jan 1993 – Feb 2020 |
| Barrow, Augusta O-10-354 | Formentera Operations LLC only | Barrow (Ellenburger) | Ector | 4 | 87.9K | 99.2K | Jan 1994 – Aug 2015 |
| TXL -L- a/C 2 O-10-16052 | Formentera Operations LLC only | TXL (Devonian) | Ector | 2 | 77.6K | 470K | Jan 1993 – Mar 2020 |
| Thomas, H. TR.1 O-10-17016 | Formentera Operations LLC only | TXL (Ellenburger) | Ector | 1 | 71.6K | 244K | Jan 1993 – Apr 2026 |
| TXL -M- O-10-15952 | Formentera Operations LLC only | TXL (Devonian) | Ector | 2 | 70.8K | 464K | Jan 1993 – Apr 2026 |
| Slator -C- O-10-35827 | Formentera Operations LLC only | TXL (Silurian) | Ector | 1 | 63.7K | 725K | Sep 1997 – Apr 2026 |
| Slator -C- O-10-16381 | Formentera Operations LLC only | TXL (Devonian) | Ector | 1 | 60K | 567K | Jan 1993 – Feb 2017 |
| Wheeler, R. A. O-10-13691 | Formentera Operations LLC only | Wheeler (Wolfcamp) | Ector | 4 | 59.6K | 154K | Jan 1993 – Apr 2026 |
| Thomas -A- O-10-6924 | Formentera Operations LLC only | TXL (Devonian) | Ector | 2 | 54K | 191K | Jan 1993 – Jan 2020 |
| TXL -L- a/C III O-10-12455 | Formentera Operations LLC only | TXL (Devonian) | Ector | 2 | 53.8K | 302K | Jan 1993 – Apr 2026 |
| Ector -H- Fee O-10-9761 | Formentera Operations LLC only | Harper | Ector | 13 | 52.5K | 29.8K | Jan 1993 – Apr 2026 |
| TXL -N- O-10-22628 | Formentera Operations LLC only | TXL (Silurian) | Ector | 2 | 51.1K | 245K | Jan 1993 – Apr 2026 |
| T. X. L. -L- a/C #1 O-10-6921 | Formentera Operations LLC only | TXL (Devonian) | Ector | 3 | 41.4K | 270K | Jan 1993 – Oct 2014 |
| Arco-Hugh Corrigan O-10-30497 | Formentera Operations LLC only | Fasken (Penn.) | Ector | 1 | 39.8K | 61.1K | Jan 1993 – Sep 2011 |
| TXL 'P' O-10-37059 | Formentera Operations LLC only | Goldsmith (Clear Fork) | Ector | 4 | 37.8K | 142K | Feb 2003 – Apr 2026 |