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Intellectual Property Litigation: Will En Banc Federal Circuit Address Assignor Estoppel?

May 13, 2020

Litigation partner Lewis Clayton’s latest intellectual property litigation column, “Will En Banc Federal Circuit Address Assignor Estoppel?” appeared in the May 13 issue of the New York Law Journal. The author discusses two recent Federal circuit cases, Hologic v. Minerva Surgical and Arista Networks v. Cisco Systems, that suggest the en banc Federal Circuit address a potential inconsistency in which an assignor can circumvent the doctrine of assignor estoppel by attacking the validity of a patent claim in the Patent Office, but cannot do the same in the district court. This doctrine is particularly significant for attorneys advising clients in transferring patent rights. Litigation associate Michael Milea assisted in the preparation of this article.

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