Icosapent ethyl is neither common nor uncommon fish oil. It's of the rarest kind: non-fish oil! No matter how many times Amarin ran fish oil through their Brita filter, it remained fish oil.
V is the result of chemical modification into a New Chemical Entity.
Fish oil is not what Amarin patented, it doesn't have the effects V does, and is not what Judge Du was supposed to be adjudicating. Hence the concern over her media comment.