Avnet, Inc. v. Motio, Inc.., No 12 C 2100, Slip Op. (N.D. Ill. Jan. 30, 2015) (Lefkow, J.).

Judge Lefkow granted defendant Motio’s motion to amend its answer and counterclaim adding counterclaims and an affirmative defense regarding inequitable conduct and related antitrust claims.

As an initial matter, while Fed. R. Civ. P. 15 requires that courts liberally allow amendment, after the deadline to amend of right has passed, Fed. R. Civ. P. 16 allows courts to grant amendment only if the party can show good cause.  Motio had good cause because it could not have identified the alleged inequitable conduct until plaintiff produced the alleged evidence.  And Motion did not unduly delay seeking amendment.  Motio waited for at least a year, but the case was not stayed for settlement discussion during much of that year.

And defendants were prejudiced by not learning of the claims until late in discovery.  But given the seriousness of the claims, the prejudice was not undue.

Finally, neither the antitrust nor the inequitable conduct claims were futile.