The Path Forward for Intervening Rights: Presaging the En Banc Decision in Marine Polymer v. Hemcon

Guest Post by Scott McKeown, Greg Gardella, and Lisa M. Mandrusiak all of OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, L.L.P.[1]

The Court of Appeals for the Federal Circuit is currently considering en banc the panel decision in Marine Polymer Technologies, Inc. v. Hemcon, Inc. The panel decision can be interpreted as suggesting that intervening rights can arise from an argument made during a post grant patent proceeding, such as a patent reexamination proceeding,[2] even if the patent owner is merely urging a claim interpretation that is consistent with the manner in which the term would have been understood at the time the underlying patent application was filed. In cases where the post grant record simply clarifies the way in which a skilled artisan would have understood a claim term at the time of filing, or reiterates the positions of the previous intrinsic record, the scope of the claims cannot properly be said to have been altered during the subsequent proceeding.

Post grant PTO patent proceedings often focus on the meaning of different aspects of originally issued claim language than were considered during the earlier application prosecution. Therefore, much of the argument made by the patent owner during the subsequent PTO proceeding is directed to new issues not previously considered by the PTO. It is to be expected that re-opening the intrinsic record via post grant file histories will often include substantively new discussion of various claim terms.

For example, during post grant proceedings patent claims are accorded the broadest reasonable interpretation ("BRI"). Determining the BRI requires a different analysis than carried out in a district court during claim construction, and notably, there is no requirement that the PTO consider the earlier prosecution record in ascertaining the BRI and meaning of an originally issued patent claim. This often places patent owners in the position of having to re-argue distinctions which were implicitly or explicitly accepted by the previous patent examiner. When the PTO requires amendment of a claim in post grant proceedings the amendment may in fact be a simple restatement of previously agreed upon claim scope, which should not give rise to intervening rights.

The rule adopted by the Court should be flexible so as to accommodate the foregoing situations and permit intervening rights only in the appropriate circumstances. The application of argument-based intervening rights should be limited to situations in which the patent owner clearly and unambiguously revises the issued claim scope by urging that a limitation has a meaning that is plainly at odds with the interpretation a court would have given the originally issued claim language.