ract ing ▁States ▁or ▁has ▁la ps ed ▁in ▁all ▁those ▁States ". ▁ ▁The ▁pat ent ▁is ▁maintained ▁in ▁an ▁am ended ▁form . ▁In ▁this ▁case , ▁a ▁new ▁pat ent ▁specification ▁is ▁published . ▁ ▁The ▁pat ent ▁is ▁rev oked . ▁This ▁is ▁the ▁most ▁successful ▁outcome ▁for ▁the ▁oppon ent , ▁although ▁the ▁maintenance ▁of ▁a ▁pat ent ▁in ▁an ▁am ended ▁form ▁may ▁also ▁be ▁regarded ▁as ▁a ▁success . ▁ ▁The ▁opposition ▁has ▁effect ▁on ▁all ▁designated ▁states ▁in ▁the ▁European ▁pat ent . ▁Dec isions ▁by ▁O pp osition ▁Div isions , ▁like ▁any ▁other ▁final ▁dec isions ▁of ▁first ▁instance ▁divisions , ▁are ▁appeal able . ▁ ▁A ▁decision ▁of ▁the ▁E PO ▁to ▁re voke ▁a ▁European ▁pat ent ▁is ▁final ▁( when ▁the ▁opportunity ▁to ▁appeal ▁before ▁the ▁E PO ▁is ▁exha usted ), ▁which ▁makes ▁the ▁opposition ▁proceed ings ▁at ▁the ▁E PO ▁especially ▁attract ive ▁for ▁oppon ents . ▁In ▁contrast , ▁a ▁decision ▁of ▁the ▁E PO ▁not ▁to ▁re voke ▁a ▁European ▁pat ent ▁( the ▁decision ▁instead ▁maintain ing ▁the ▁pat ent ▁as ▁granted ▁or ▁in ▁an ▁am ended ▁form ) ▁leaves ▁the ▁way ▁open ▁for ▁rev ocation ▁by ▁the ▁national ▁court . ▁The ▁E PO ▁decision ▁does ▁not ▁create ▁an ▁est opp el ▁pre cluding ▁a ▁subsequent ▁challenge ▁by ▁an ▁un success ful ▁oppon ent ▁at ▁the ▁national ▁level ▁( at ▁least ▁before ▁the ▁English ▁courts ). ▁The ▁valid ity ▁of ▁a ▁European ▁pat ent ▁can