I love stuff like this…
Watson files an ANDA; Bayer sues, triggering an automatic 30 month stay of the ANDA. Judge grants judgment on the pleadings to Watson, which is affirmed on appeal. District judge later denies request by Watson for "exceptional case" under 285.
Later, Watson sues Bayer in state court, alleging malicious prosecution and other state law claims. Boiled down, it asserts Bayer filed the infringement suit for an improper purpose — to trigger the 30 month stay. Bayer removes the case to federal court. Judge denies the motion to remand, though honestly I'm not quite sure why!