The Federal Circuit Court of Appeals, in the context of patents on improvements to electronic animal collars, has in large part affirmed a lower court judgment of non-infringement, but refused to consider an alternative ground of patent invalidity to affirm the entire judgment because the alleged infringer did not cross-appeal the lower court’s denial of its summary judgment motion on the invalidity issue. Radio Sys. Corp. v. Lalor, No. 2012-1233 (Fed. Cir., decided March 6, 2013).

According to the panel majority, “a judgment of invalidity is broader than a judgment of noninfringement. ‘[A] determination of infringement applies only to a specific accused product or process, whereas invalidity operates as a complete defense to infringement for any product, forever.’ Thus, invalidity cannot be an alternative ground for affirming a judgment of noninfringement absent a cross-appeal.” Judge Pauline Newman, concurring in part and dissenting in part, would have held that the alleged infringer “was not required to filed a cross-appeal, for as prevailing party it had no right of appeal” and the “prevailing party need not file a cross-appeal in order to defend a judgment in its favor on any ground that is supported by the record.” Newman further noted that issue was fully addressed by the lower court and fully briefed by the alleged infringer. She also concluded, “Since validity was not considered on the appeal to this court, it may be considered in the remand proceeding.”

The Federal Circuit remanded the matter for further proceedings in light of its determination that the lower court abused its discretion in relying on equitable estoppel to rule that one of the patents was not infringed.