| Courson Handley 565 #2VHHZ42-357-32746 | Highmark Energy Operating LLC | Ochiltree, TXDutcher (Atoka) | ActiveOil | 8,584 | Jun 13, 2008 | — | — |
| Conroe Field Unit #4040D42-339-30414 | Highmark Energy Operating LLC | Montgomery, TXConroe | ActiveInjection | 12,004 | May 29, 2008 | — | — |
| Cooper 445 #3HHZ42-295-33337 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,126 | May 28, 2008 | — | — |
| Jones Trust 359 #2HHZ42-295-33322 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveGas | 8,389 | May 15, 2008 | — | — |
| Lowe M. R. 15 #442-003-40482 | Highmark Energy Operating LLC | Andrews, TXFullerton | ActiveOil | 7,350 | Apr 25, 2008 | — | — |
| CNB Trustees 360 #3HHZ42-295-33312 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | PluggedOil | 9,000 | Apr 22, 2008 | — | — |
| Appel 438 #3HHZ42-295-33328 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Atoka) | ActiveGas | 9,768 | Apr 21, 2008 | — | — |
| Jones Trust 359 #3HHZ42-295-33326 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | PluggedOil | 9,000 | Apr 16, 2008 | — | — |
| Cooper 445 #2HHZ42-295-33323 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,126 | Apr 14, 2008 | — | — |
| Cooper 358 #3HHZ42-295-33324 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,381 | Apr 14, 2008 | — | — |
| Prentice Northeast Unit #2131E42-445-32200 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,283 | Apr 11, 2008 | — | — |
| Cooper 435 #2HHZ42-295-33317 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | PluggedOil | 9,000 | Apr 4, 2008 | — | — |
| Cooper 436 #3HHZ42-295-33318 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,171 | Apr 4, 2008 | — | — |
| Daniel 586 #1HHZ42-357-32726 | Highmark Energy Operating LLC | Ochiltree, TXPerryton (Novi Lower) | ActiveGas | 8,771 | Mar 27, 2008 | — | — |
| Prentice Northeast Unit #2113E42-445-32198 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | Shut inOil | 7,326 | Mar 27, 2008 | — | — |
| Prentice Northeast Unit #1839N42-445-32199 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveOil | 7,175 | Mar 27, 2008 | — | — |
| Trosper Corwin 431 #4HHZ42-295-33307 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 10,617 | Mar 19, 2008 | — | — |
| Cooper 435 #1HHZ42-295-33308 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | PluggedOil | 9,000 | Mar 19, 2008 | — | — |
| Courson Parnell 405 #2HHZ42-357-32723 | Highmark Energy Operating LLC | Ochiltree, TXDutcher (Atoka) | ActiveGas | 8,805 | Mar 19, 2008 | — | — |
| Appel 438 #242-295-33305 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Atoka 9200) | ActiveGas | 10,250 | Mar 17, 2008 | — | — |
| Cooper 445 #1HHZ42-295-33306 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Shut inOil | 8,151 | Mar 13, 2008 | — | — |
| Price WD -B- #10HHZ42-295-33289 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveGas | 7,792 | Feb 27, 2008 | — | — |
| Barton 346 #6HHZ42-295-33299 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,420 | Feb 20, 2008 | — | — |
| Tyson D. R. #5623HHZ42-295-33255 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveGas | 7,881 | Dec 28, 2007 | — | — |
| Schultz Brothers C #2HHZ42-295-33256 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Temporarily abandonedGas | 7,681 | Nov 29, 2007 | — | — |
| Peery 733 #6HHZ42-295-33242 | Highmark Energy Operating LLC | Lipscomb, TXPeery (Cleveland) | Shut inOil | 7,368 | Nov 27, 2007 | — | — |
| Prentice Northeast Unit #1042-445-00563 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 7,000 | Oct 26, 2007 | — | — |
| Lowe M. R. 15 #642-003-40280 | Highmark Energy Operating LLC | Andrews, TXFullerton | ActiveOil | 7,270 | Oct 25, 2007 | — | — |
| Hunter 676 #3HHZ42-295-33241 | Highmark Energy Operating LLC | Lipscomb, TXPeery (Cleveland) | ActiveOil | 7,377 | Oct 24, 2007 | — | — |
| Minium 734 #4HHZ42-295-33240 | Highmark Energy Operating LLC | Lipscomb, TXPeery (Cleveland) | ActiveOil | 7,340 | Oct 17, 2007 | — | — |
| Weidner 798 #4HHZ42-295-33239 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 7,699 | Oct 15, 2007 | — | — |
| Prentice Northeast Unit #13942-445-30109 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | PluggedOil | 6,017 | Aug 18, 2007 | — | — |
| Mitchell 763 #7HHZ42-295-33217 | Highmark Energy Operating LLC | Lipscomb, TXPeery (Cleveland) | ActiveOil | 7,380 | Aug 10, 2007 | — | — |
| Cooper 436 #2HHZ42-295-33218 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Shut inOil | 8,255 | Aug 10, 2007 | — | — |
| Jones Trust 359 #1VHHZ42-295-33219 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | PluggedOil | 9,000 | Aug 10, 2007 | — | — |
| Cooper 357 #1HHZ42-295-33202 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Shut inOil | 8,377 | Jul 13, 2007 | — | — |
| Prentice Northeast Unit #42W42-445-00517 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 6,876 | May 10, 2007 | — | — |
| Martin 800 #5HHZ42-295-33154 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 7,703 | Apr 20, 2007 | — | — |
| Peery 733 #5HHZ42-295-33175 | Highmark Energy Operating LLC | Lipscomb, TXPeery (Cleveland) | Shut inOil | 7,389 | Apr 19, 2007 | — | — |
| Perry Heirs #142-339-00817 | Highmark Energy Operating LLC | Montgomery, TXConroe (Cons. L) | Temporarily abandonedGas | 5,120 | Apr 16, 2007 | — | — |
| Cooper 358 #2HHZ42-295-33153 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Shut inOil | 8,360 | Mar 2, 2007 | — | — |
| Cooper 348 #4HHZ42-295-33145 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,488 | Feb 26, 2007 | — | — |
| Cooper 348 #3HHZ42-295-33146 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,398 | Feb 26, 2007 | — | — |
| Barton 346 #4HHZ42-295-33147 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | Shut inOil | 8,438 | Feb 26, 2007 | — | — |
| Barton 346 #5HHZ42-295-33148 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,515 | Feb 26, 2007 | — | — |
| CNB G 345 #12HHZ42-295-33136 | Highmark Energy Operating LLC | Lipscomb, TXLipscomb (Cleveland) | ActiveOil | 8,356 | Feb 1, 2007 | — | — |
| Prentice Northeast Unit #942-445-00097 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | Shut inOil | 7,350 | Jan 30, 2007 | — | — |
| Prentice Northeast Unit #148W42-445-30846 | Highmark Energy Operating LLC | Terry, TXPrentice (6700) | ActiveInjection | 7,360 | Jan 30, 2007 | — | — |
| Weis 452 #242-295-32903 | Highmark Energy Operating LLC | Lipscomb, TXTrosper (Atoka) | ActiveGas | 9,750 | Jan 17, 2007 | — | — |
| Pshigoda-Courson 572 #4HHZ42-357-32645 | Highmark Energy Operating LLC | Ochiltree, TXPan Petro (Cleveland) | ActiveGas | 7,048 | Jan 11, 2007 | — | — |