| Harper Unit O-2-9508 | EOG Resources, Inc. only | Eagleville (Eagle Ford-2) | Karnes | 23 | 4.05M | 9.02M | Dec 2010 – Apr 2026 |
| East Harper Unit O-10-19904 | Aghorn Operating, Inc. only | Harper | Ector | 266 | 2.95M | 843K | Jan 1993 – Feb 2026 |
| Harper Devonian Unit O-10-20609 | OXY USA WTP EOR, LLC only | Harper (Devonian) | Ector | 42 | 2.33M | 16M | 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 |
| Moss -E- O-10-17665 | OXY USA WTP EOR, LLC only | Harper (Ellenburger) | Ector | 7 | 601K | 601K | Jan 1993 – Apr 2026 |
| Moss O-10-2470 | Walsh & Watts, Inc. only | Harper | Ector | 27 | 601K | 238K | Jan 1993 – Apr 2026 |
| Cowden -13- O-10-31983 | Aghorn Operating, Inc. only | Harper (Glorieta) | Ector | 9 | 600K | 210K | Jan 1993 – Feb 2026 |
| Harper, H. O-6-12912 | Linder, John Operating Co., LLC only | AD-AM (Paluxy) | Wood | 1 | 538K | 117 | Jan 1993 – Apr 2026 |
| Harper Ferry 54-4-29 G-10-283225 | Anadarko E&P Onshore LLC only | Phantom (Wolfcamp) | Reeves | 1 | 499K | 2.02M | Mar 2019 – Apr 2026 |
| Harper, R. H. & L. O-6-1635 | IV Standard, LLC only | Talco | Titus | 5 | 497K | 32 | Jan 1993 – Apr 2026 |
| TXL -A- O-10-2472 | Walsh & Watts, Inc. only | Harper | Ector | 11 | 476K | 98.9K | Jan 1993 – Apr 2026 |
| Parker -D- O-10-2471 | Walsh & Watts, Inc. only | Harper | Ector | 17 | 452K | 250K | Jan 1993 – Apr 2026 |
| Harper A O-9-18201 | Discovery Natural Resources LLC only | Lin (Wolfcamp) | Irion | 4 | 405K | 2.09M | Apr 2013 – Apr 2026 |
| Cowden -12- O-10-32108 | Aghorn Operating, Inc. only | Harper (Glorieta) | Ector | 10 | 378K | 164K | Jan 1993 – Feb 2026 |
| TXL -WW- O-10-17917 | Burleson Petroleum, Inc. only | Harper (Ellenburger) | Ector | 1 | 366K | 313K | Jan 1993 – Apr 2026 |
| Moss O-10-17240 | Aghorn Operating, Inc. only | Harper (Ellenburger) | Ector | 4 | 357K | 422K | Jan 1993 – Feb 2026 |
| Harper 1-12 O-10-49339 | Pioneer Natural Res. USA, Inc. only | Spraberry (Trend Area) | Midland | 1 | 336K | 1.17M | Jul 2017 – Mar 2026 |
| Fraser, Geo. C. O-10-18018 | Burleson Petroleum, Inc. only | Harper (Ellenburger) | Ector | 2 | 309K | 167K | Jan 1993 – Apr 2026 |
| Harper Unit O-1-18535 | Verdun Oil EF II LLC only | Eagleville (Eagle Ford-1) | La Salle | 2 | 287K | 904K | Aug 2015 – Apr 2026 |
| Harper '1-12' O-10-49482 | Pioneer Natural Res. USA, Inc. only | Spraberry (Trend Area) | Midland | 1 | 259K | 910K | Jul 2017 – Apr 2026 |
| TXL O-10-9280 | Burleson Petroleum, Inc. only | Harper | Ector | 5 | 253K | 125K | Jan 1993 – Apr 2026 |
| Harper Unit O-2-9379 | EOG Resources, Inc. only | Eagleville (Eagle Ford) | Karnes | 9 | 251K | 297K | Jan 2010 – Nov 2010 |
| Harper Allocation A G-1-298943 | Verdun Oil EF II LLC only | Eagleville (Eagle Ford-1) | La Salle | 1 | 200K | 366K | Dec 2024 – Apr 2026 |
| Cowden Ranch -6- O-10-32731 | Rust Oil Corp. only | Harper (Glorieta) | Ector | 1 | 197K | 23K | Jan 1993 – Apr 2026 |
| Wright -14- O-10-32230 | Aghorn Operating, Inc. only | Harper (Glorieta) | Ector | 2 | 195K | 28.6K | Jan 1993 – Feb 2026 |
| Parker, J. E. O-10-8549 | Shinnery Oil Company, Inc. only | Harper | Ector | 9 | 176K | 68.6K | Jan 1993 – Apr 2026 |
| Fraser, George C. "B" O-10-36214 | Burleson Petroleum, Inc. only | Harper (Strawn) | Ector | 1 | 171K | 280K | Mar 2000 – Apr 2026 |
| Parker, J. E. O-10-2443 | Acoma Operating, LLC only | Harper | Ector | 22 | 167K | 132K | Jan 1993 – Apr 2026 |
| Ector Fee Unit O-10-34363 | Aghorn Operating, Inc. only | Harper (Fusselman) | Ector | 1 | 165K | 242K | Dec 1994 – Feb 2026 |
| Moss O-10-17241 | Aghorn Operating, Inc. only | Harper (Strawn) | Ector | 4 | 163K | 151K | Jan 1993 – Feb 2026 |
| W. E. Cowden O-10-27887 | Baker Operating, Inc. only | Harper | Ector | 9 | 156K | 57.6K | Jan 1993 – Apr 2026 |
| Cowden O-10-33431 | Petex only | Harper, W. (Pennsylvanian) | Ector | 2 | 151K | 128K | Jan 1993 – Apr 2026 |
| Parker "A" O-10-2468 | Walsh & Watts, Inc. only | Harper | Ector | 15 | 151K | 254K | Jan 1993 – Apr 2026 |
| Harper Unit C Dim O-1-16511 | Ineos USA Oil & Gas LLC only | Briscoe Ranch (Eagleford) | Dimmit | 1 | 134K | 208K | Mar 2013 – Apr 2026 |
| Harper-Dietze B G-1-298979 | Verdun Oil EF II LLC only | Eagleville (Eagle Ford-1) | La Salle | 1 | 133K | 215K | Dec 2024 – Apr 2026 |
| Parker "B" O-10-2469 | Walsh & Watts, Inc. only | Harper | Ector | 13 | 123K | 129K | Jan 1993 – Apr 2026 |
| Harper Unit B Dim O-1-16166 | Ineos USA Oil & Gas LLC only | Briscoe Ranch (Eagleford) | Dimmit | 1 | 118K | 163K | Oct 2012 – Nov 2023 |
| Ector -AR- Fee O-10-18196 | Pen-Tex Production Co. Inc. only | Harper | Ector | 18 | 115K | 81.9K | Jan 1993 – Apr 2026 |
| Parker "A" O-10-2459 | Acoma Operating, LLC only | Harper | Ector | 6 | 114K | 8.41K | Jan 1993 – Mar 2026 |
| Moss, Paul -C- O-10-11169 | Aghorn Operating, Inc. only | Harper | Ector | 32 | 106K | 51.3K | Jan 1993 – Feb 2026 |
| Parker O-10-27704 | Pen-Tex Production Co. Inc. only | Harper | Ector | 5 | 105K | 149K | 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 |
| Cowden, E. F. -a- - -B- O-10-2453 | Aghorn Operating, Inc. only | Harper | Ector | 17 | 103K | 36.4K | Jan 1993 – Feb 2026 |
| TXL O-10-2460 | Walsh & Watts, Inc. only | Harper | Ector | 5 | 103K | 2.23K | Jan 1993 – Apr 2026 |
| Moss, Paul '34' O-10-2452 | Aghorn Operating, Inc. only | Harper | Ector | 14 | 102K | 1.44K | Jan 1993 – Feb 2026 |
| Ector -E- Fee NCT-2 O-10-17723 | Formentera Operations LLC only | Harper (Ellenburger) | Ector | 2 | 100K | 107K | Dec 1996 – Sep 2015 |
| Harper-Bayes 16 O-10-44283 | Diamondback E&P LLC only | Spraberry (Trend Area) | Martin | 1 | 99.8K | 182K | Jul 2013 – Apr 2026 |
| Harper "A" O-6-12515 | Faulconer Energy, LLC only | Laneville, NE. (Pettit, Lo.) | Rusk | 2 | 99.6K | 608K | Jan 1993 – Apr 2026 |
| Diamond Lil O-10-36719 | Hilcorp Energy Company only | Harper (Ellenburger) | Ector | 1 | 89.2K | 59.8K | Jul 2001 – Apr 2026 |
| Cowden-Oliver O-10-29350 | Baker Operating, Inc. only | Harper | Ector | 6 | 88K | 60K | Jan 1993 – Apr 2026 |