In an opinion addressing prosecution history estoppel, the US
Court of Appeals for the Federal Circuit affirmed a district
court's decision granting summary judgment of non-infringement,
finding that the patentee was estopped from including certain
subject matter within the scope of an asserted claim when other
claims directed to that subject matter had been canceled during
prosecution. UCB, Inc. v. Yeda Research and Development Co.,
Ltd., Case No. 15-1957 (Fed. Cir., Sept. 8, 2016) (Newman,
J).
UCB sued Yeda in district court, seeking declaratory judgment as
to non-infringement and invalidity of a patent with claims directed
to a monoclonal antibody. The question was whether the scope of the
asserted claim included chimeric and humanized antibodies, or only
murine (mouse) antibodies, the latter being the only antibodies
described in the specification. Yeda argued that humanized and
chimeric antibodies should be included because they were known in
the art as of the
