In Massachusetts Institute of Technology v. Shire Pharmaceuticals, Inc., [2015-1881] (October 13, 2016), the Federal Circuit affirmed the district court’s construction of “vascularized organ tissue” and “cells derived from a vascularized tissue” and its determination that the term “three-dimensional scaffold” was not indefinite, and thus the parties stipulated to a final judgment of validity and infringement stands.

The Federal Circuit said that the doctrine of prosecution disclaimer precludes patentees from recapturing through claim interpretation specific meanings disclaimed during prosecution. In order for prosecution disclaimer to attach, the disavowal must be both clear and unmistakable.  Where the alleged disavowal is ambiguous, or even amenable to multiple reasonable interpretations, the Federal Circuit said that it has declined to find prosecution disclaimer.

On the first term, “vascularized organ tissue,” the district court determined that there was no clear and unmistakable disclaimer that would exclude skin from the term’s ordinary meaning, and construed the term “vascularized organ tissue” as “vascularized tissue from an organ,” reasoning that because “the dermal layer of skin contains blood vessels, this term encompasses skin,” and the Federal Circuit agreed. The Federal Circuit analyzed the statements identified by Shire in the context of the claims pending at the time they were made.  Federal Circuit determined that a skilled artisan, reading the prosecution history as a whole, would conclude that MIT’s invention does in fact cover vascularized skin.

The Federal Circuit also agreed with the district court’s construction of “cells derived from a vascularized tissue” to include both parenchymal and non-parenchymal cells, noting that the claims themselves do not make a distinction.  After reading the full prosecution history in light of the then-pending claim language, the Federal Circuit concluded that a skilled artisan would not read MIT’s statements made during prosecution — and directed to very different claim language — as limiting the term “cells derived from a vascularized tissue” to parenchymal cells.

Lastly with respect to the district court’s determination that the term “three-dimensional scaffold” is not indefinite, the Federal Circuit affirmed the district court’s claim construction and validity determination.  While Shire asserted that there was no definition of “three-dimensional,” the district court construed the term “three dimensional” according to its accepted, ordinary meaning, as confirmed by dictionary definitions. Shire complained that these were current, non-technical dictionaries, but the Federal Circuit pointed out that Shire failed to show how technical dictionaries or dictionaries contemporaneous to the patents’ filing date would define the term any differently, and in fact the definitions were consistent with Shires own experts.