| Abraxas Petroleum Corporation |
003125 |
| Americo Energy Resources, LLC |
019752 |
| Apache Corporation |
027200 |
| Arch Oil & Gas, LLC |
029272 |
| Arkland Producing Co., Inc. |
030791 |
| Atropos Production Corporation |
036617 |
| Basa Resources, Inc. |
053974 |
| Baylor Operating, LLC |
058832 |
| Bettis, Boyle & Stovall |
068360 |
| Big D Energy Company |
069344 |
| Bills, L. T. |
070882 |
| Birch Operations, Inc. |
071331 |
| Boyd & McWilliams Energy Group |
084545 |
| Breitburn Operating L.P. |
090732 |
| Bta Oil Producers, LLC |
041867 |
| Buchanan, Billy R. |
105270 |
| Byrd Operating Company |
118748 |
| Callon Petroleum Operating Co |
124828 |
| Cambrian Management, LTD. |
126758 |
| Campana Petroleum Company |
127700 |
| Charter Petroleum Company |
146680 |
| Chevron U. S. A. Inc. |
148113 |
| Chisos Operating, Inc. |
149441 |
| Cholla Petroleum, Inc. |
150683 |
| Cimarex Energy Co. Of Colorado |
153429 |
| Cinnabar Operating, LLC |
153510 |
| Circle H Oil Company |
153656 |
| Citation Oil & Gas Corp. |
154235 |
| Clear Water Inc. |
159643 |
| Cobra Oil & Gas Corporation |
163000 |
| Cog Operating LLC |
166150 |
| Conocophillips Company |
172232 |
| Cooper Oil & Gas, LLC |
175118 |
| Cordero Energy Operating LLC |
178200 |
| Crownquest Operating, LLC |
191554 |
| Dallas Production, Inc. |
197690 |
| De3 Operating LLC |
518310 |
| Desert Production, Inc. |
216556 |
| Diamondback E&P LLC |
217012 |
| Dinero Operating Company |
220711 |
| Discovery Operating, Inc. |
220865 |
| Double Eagle Operating, LLC |
224857 |
| Duncan Drilling Co. |
232050 |
| Encana Oil & Gas(USA) Inc. |
251691 |
| Endeavor Energy Resources L.P. |
251726 |
| Energen Resources Corporation |
252002 |
| Excel Energy Co. |
256873 |
| Finley Resources, Inc. |
268602 |
| Foundation Energy Management LLC |
280875 |
| Golden Specialties Oil & Gas |
313070 |
| Grenadier Energy Partners II,LLC |
332472 |
| Haimo Oil & Gas LLC |
343095 |
| Hall Oil & Gas |
345972 |
| Hankamer, Curtis Corporation,The |
354081 |
| Hannathon Petroleum, LLC |
354954 |
| Harmonia Pet Operations, LLC |
357480 |
| Hartoil Corporation |
362980 |
| Helms Oil & Gas, LLC |
374347 |
| Hendrix, John H. Corporation |
378256 |
| Highpeak Energy Holdings, LLC |
385826 |
| HX Oil |
421129 |
| Ica Energy Operating, L.L.C. |
421777 |
| Jay Management Company, LLC |
430368 |
| Just Oil & Gas, Inc. |
448220 |
| J V A Operating Company, Inc. |
427911 |
| Kaiser-Francis Oil Company |
450175 |
| Karico GP, LLC |
451075 |
| Kebo Oil & Gas, Inc. |
453170 |
| Keeley Oil, L.L.C. |
453380 |
| King Energy Resources |
465526 |
| Lackey, William H. Oil And Gas |
480868 |
| Lakewood Operating, LTD. |
483615 |
| Laredo Petroleum, Inc. |
486610 |
| L.C.S. Production Company |
479574 |
| Legacy Reserves Operating LP |
495445 |
| Lynx Operating Co., Inc. |
516255 |
| Manhattan Petroleum, Inc. |
524391 |
| McClure Oil Company, Inc. |
540703 |
| MDC Operating, Inc. |
556484 |
| Merit Energy Company |
561136 |
| MGM Oil & Gas Company |
563329 |
| Midland Oil And Gas, Inc. |
565589 |
| Millennium Resources, LP |
567484 |
| Millwee Oil, Inc. |
569339 |
| Miltex Oil Company |
569415 |
| Mineral Technologies, Inc. |
593635 |
| Moss Petroleum Company |
590920 |
| MSD Operating, LLC |
592471 |
| Mulloy Operating, Inc. |
593077 |
| MWS Producing, Inc. |
597379 |
| Nichols,Edwin S Explorations Inc |
610207 |
| Nordstrand Engineering, Inc. |
612858 |
| Occidental Permian LTD. |
617544 |
| O'Ryan Oil And Gas |
617042 |
| Oxy USA Inc. |
630591 |
| Ozark Exploration, Inc. |
630611 |
| P4 Operating, LLC |
631638 |
| Paladin Petroleum III, L.L.C. |
635107 |
| Pangea Corporation |
637942 |
| Parsley Energy Operations, LLC |
642652 |
| Partee Drilling Inc. |
642702 |
| Pearl, Bill H. Productions, Inc. |
647284 |
| Perry Producing Company, Inc. |
658560 |
| Petroplex Energy Inc. |
660886 |
| Petroplex Equipment, Inc. |
660854 |
| Pioneer Natural Res. USA, Inc. |
665748 |
| Primal Energy Corporation |
677741 |
| Probe Exploration Company |
679299 |
| RCW Oil Company |
695718 |
| RCW Oil, LLC |
695696 |
| Rein Pusher Operating LLC |
700148 |
| Robertson Resources, Inc. |
718770 |
| Rover Petroleum Operating, LLC |
730462 |
| Royalty Land & Dev. Co., Inc. |
731988 |
| RP Operating, L.L.C. |
732229 |
| Ruwco Oil And Gas Corp. |
739825 |
| Sabalo Operating, LLC |
741939 |
| Sahara Operating Company |
743279 |
| Schlachter Operating Corporation |
753981 |
| Scout Energy Management LLC |
760218 |
| Seely Oil Company |
763148 |
| Shamrock Upstream Energy LLC |
769112 |
| Sharp Image Energy, Inc. |
770731 |
| Shenandoah Petroleum Corporation |
775563 |
| Shenandoah Resources LLC |
775564 |
| Sheridan Production Company, LLC |
775854 |
| SMC Oil & Gas, Inc. |
789634 |
| SM Energy Company |
788997 |
| Sojourner Drilling Corporation |
800750 |
| Southwest Royalties, Inc. |
806470 |
| Surge Operating, LLC |
760725 |
| Sutton Oil Co. |
831235 |
| Taylor Two Energy, LLC |
837430 |
| Thompson, J. Cleo |
855610 |
| Three Span Oil & Gas, Inc. |
857911 |
| Trilogy Operating, Inc. |
869713 |
| Triton Operating LLC |
871166 |
| Unitex Oil & Gas, L.L.C. |
877921 |
| Unit Petroleum Company |
877099 |
| Valence Operating Company |
881167 |
| V-F Petroleum Inc. |
880375 |
| Vision Natural Resources, LP |
886256 |
| Wagner Oil Company |
891175 |
| Walsh & Watts, Inc. |
895060 |
| Wash, Robert C. Inc. |
899038 |
| Whiting Oil And Gas Corporation |
920478 |
| WTG Exploration |
945220 |