Judge Leinenweber granted defendants' motion to amend their answers including new invalidity and unenforceability affirmative defenses and counterclaims in this ANDA patent case involving plaintiff's patented pharmaceutical OLUX.  The Court held that the amended answers and counterclaims were appropriate because they were filed before the Court's deadline for amended pleadings, even though the parties briefed the motion to amend as if the amendment was sought after the deadline.  Furthermore, defendants did not unduly delay in seeking to amend.  The motion to amend was filed within several months of depositions in which new information necessary for the amendments was disclosed.  And the litigation was still in its early stages so the amendments would not cause any prejudice.