| University San Andres Unit #20W42-003-38862 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | PluggedOil | 4,800 | Aug 16, 2001 | — | — |
| University San Andres Unit #21W42-003-38863 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | ActiveInjection | 4,790 | Aug 16, 2001 | — | — |
| University San Andres Unit #26W42-003-38864 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | Shut inOil | 4,800 | Aug 16, 2001 | — | — |
| University San Andres Unit #27W42-003-38865 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | ActiveInjection | 4,800 | Aug 16, 2001 | — | — |
| University San Andres Unit #28W42-003-38866 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | ActiveInjection | 4,785 | Aug 16, 2001 | — | — |
| University San Andres Unit #33W42-003-38867 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | Shut inOil | 4,800 | Aug 16, 2001 | — | — |
| University San Andres Unit #34W42-003-38868 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | Shut inOil | 4,800 | Aug 16, 2001 | — | — |
| University San Andres Unit #842-003-38869 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | Shut inOil | 4,757 | Aug 16, 2001 | — | — |
| University San Andres Unit #3742-003-10505 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (San Andres) | PluggedOil | 7,108 | Aug 9, 2001 | — | — |
| Keystone Mills #4642-339-31000 | Highmark Energy Operating LLC | Montgomery, TXWildcat | ActiveGas | 10,925 | Aug 9, 2001 | — | — |
| Prentice Northeast Unit #66642-445-31721 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,162 | Aug 6, 2001 | — | — |
| Alenius-Chisolm #142-339-00771 | Highmark Energy Operating LLC | Montgomery, TXWildcat | Shut inOil | 5,181 | Aug 3, 2001 | — | — |
| Moorehead A. #242-339-01857 | Highmark Energy Operating LLC | Montgomery, TXConroe (Cons. U) | Temporarily abandonedGas | 5,157 | Jul 25, 2001 | — | — |
| Williamson Unit #442-401-33124 | Highmark Energy Operating LLC | Rusk, TXOak Hill (Cotton Valley) | PluggedGas | 11,000 | Jun 6, 2001 | — | — |
| Keystone Mills #4042-339-30608 | Highmark Energy Operating LLC | Montgomery, TXConroe (Middle Wilcox Cons.) | ActiveOil | 11,140 | May 25, 2001 | — | — |
| Conroe Field Unit #150742-339-00826 | Highmark Energy Operating LLC | Montgomery, TXConroe | PluggedOil | 5,156 | May 18, 2001 | — | — |
| Conroe Field Unit #90342-339-00535 | Highmark Energy Operating LLC | Montgomery, TXConroe | PluggedOil | 5,186 | May 2, 2001 | — | — |
| Fairway/James Lime/Unit #35142-213-00550 | Highmark Energy Operating LLC | Henderson, TXFairway (James Lime) | ActiveGas | 9,959 | Apr 19, 2001 | — | — |
| Fairway/James Lime/Unit #25642-213-00551 | Highmark Energy Operating LLC | Henderson, TXFairway (James Lime) | ActiveGas | 9,959 | Apr 19, 2001 | — | — |
| Prentice Northeast Unit #52342-445-31961 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,315 | Mar 30, 2001 | — | — |
| Prentice Northeast Unit #53442-445-31962 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,400 | Mar 30, 2001 | — | — |
| Prentice Northeast Unit #29942-445-31951 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 7,430 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #72442-445-31952 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 7,291 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #68842-445-31953 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,070 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #59042-445-31954 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,383 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #64642-445-31955 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,400 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #58942-445-31956 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | Shut inOil | 7,451 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #58742-445-31957 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,405 | Mar 20, 2001 | — | — |
| Prentice Northeast Unit #54742-445-31958 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,262 | Mar 20, 2001 | — | — |
| Conroe Field Unit #70342-339-00342 | Highmark Energy Operating LLC | Montgomery, TXConroe | PluggedOil | 5,151 | Mar 13, 2001 | — | — |
| Fairway /James Lime/ Unit #250242-213-30022 | Highmark Energy Operating LLC | Henderson, TXFairway (James Lime) | PluggedOil | 10,048 | Jan 29, 2001 | — | — |
| University -C- #642-003-38720 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (Devonian) | Shut inOil | 9,964 | Jan 2, 2001 | — | — |
| Fairway /James Lime/ Unit #742342-213-30817 | Highmark Energy Operating LLC | Henderson, TXFairway (James Lime) | PluggedOil | 10,500 | Dec 27, 2000 | — | — |
| University -F- #342-003-07312 | Highmark Energy Operating LLC | Andrews, TXShafter Lake (Clear Fork) | ActiveOil | 9,932 | Nov 16, 2000 | — | — |
| Conroe Field Unit #400642-339-01289 | Highmark Energy Operating LLC | Montgomery, TXConroe | PluggedOil | 10,000 | Nov 8, 2000 | — | — |
| Rhodes W. S. #1942-339-30974 | Highmark Energy Operating LLC | Montgomery, TXConroe (Cons. L) | Shut inOil | 3,944 | Oct 11, 2000 | — | — |
| Hansford Gas Unit 26 #342-195-31466 | Highmark Energy Operating LLC | Hansford, TXHansford (Morrow Upper) | ActiveGas | 8,100 | Oct 5, 2000 | — | — |
| Hightower et al GU 1 #242-213-30806 | Highmark Energy Operating LLC | Henderson, TXMoore Station (James Lime) | Temporarily abandonedGas | 10,798 | Sep 8, 2000 | — | — |
| Conroe Field Unit #206942-339-30422 | Highmark Energy Operating LLC | Montgomery, TXConroe | Temporarily abandonedGas | 9,255 | Sep 7, 2000 | — | — |
| Hansford Gas Unit 21 #242-195-31453 | Highmark Energy Operating LLC | Hansford, TXHansford (Morrow Lower) | ActiveGas | 8,100 | Aug 30, 2000 | — | — |
| Parker Harry B #342-295-32543 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Morrow) | ActiveGas | 10,600 | Aug 30, 2000 | — | — |
| Prentice Northeast Unit #68442-445-31927 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,085 | Aug 10, 2000 | — | — |
| Prentice Northeast Unit #50242-445-31928 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,390 | Aug 10, 2000 | — | — |
| Moore H. N. #4642-339-01489 | Highmark Energy Operating LLC | Montgomery, TXConroe (Cons. L) | Temporarily abandonedGas | 5,200 | Aug 8, 2000 | — | — |
| Prentice Northeast Unit #28042-445-31922 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,440 | Jul 26, 2000 | — | — |
| Prentice Northeast Unit #53242-445-31923 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,370 | Jul 26, 2000 | — | — |
| Prentice Northeast Unit #564U42-445-31924 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 7,425 | Jul 26, 2000 | — | — |
| Prentice Northeast Unit #58442-445-31925 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | Shut inOil | 7,365 | Jul 26, 2000 | — | — |
| Hale 133 #142-195-31438 | Highmark Energy Operating LLC | Hansford, TXHansford (Morrow Upper) | ActiveGas | 7,650 | Jun 14, 2000 | — | — |
| Mathews 2 #142-195-31439 | Highmark Energy Operating LLC | Hansford, TXHansford (Morrow Lower) | ActiveGas | 7,950 | Jun 14, 2000 | — | — |