I assume that Amphastar knows they are infringing if they are, which brings up the question why would they spend the time/money to get their application approvable if they were just going to have to face the prospect of litigation?
In addition to what iwfal said in #msg-67343915, bear in mind that the two patents that MNTA alleges are infringed were not issued by the USPTO until Aug 2009 and Sep 2010, respectively; until then, Amphastar could not have known that it was infringing on another company’s issued patents.
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