In the latest installment of their Law360 column on recent noteworthy Federal Circuit decisions, partners Sean Murray and Jeremiah Helm examined the outcome in Eye Therapies LLC v. Slayback Pharma LLC. The case addresses the interpretation of the phrase “consisting essentially of,” a transitional phrase that is relatively uncommon in patent claims.
Murray and Helm note that transitional phrases are “rarely the subject of a substantive dispute” in patent litigation, making Eye Therapies an informative case for practitioners and patentees alike. They analyze how the patentee’s choice to use this transitional phrasing, as well as definitional language containing the abbreviation “i.e.”, influenced the Federal Circuit’s conclusion that the patentee had redefined a term that ordinarily has a well-understood, fixed meaning in patent law. The authors recommend that attorneys exercise caution when restating claim language, using “i.e.” or otherwise, as this “may be considered a redefinition of the claim language in subsequent litigation.”
Read the full article here.