bouf-not ALL mistakes--but complex/sophisticated mistakes, such as statistics, which patent attorneys are not necessarily expected to know--should be a "mistake" per R. 60
That will be the crux of the argument (not whether Bhatt is correct) but rather whether amrn's attorneys should have know the statistical mistake during appeal.
In any event I think Du will just deny the motion to intervene since shareholders are represented by amrn's professional lawyers. So the case won't get off the ground--and you know how nice the appeal court is :)