Federal Circuit
Resolves intervening rights
In polymer case

The Federal Circuit Court of Appeals has reversed an earlier decision that had created uncertainly about the rights of an infringer resulting from patent reexamination proceedings.

In Marine Polymer Technologies, Inc. v. HemCon, Inc., 2012 U.S. App. LEXIS 5567 (Fed. Cir., March 15, 2012), the Federal Circuit held that intervening rights arise in a patent reexamination only when the claims have been amended or are new. 

Marine Polymer sued HemCon for infringement of its U.S. Patent No. 6,864,245, related to p-GlcNAc, a polymer that accelerates hemostasis (i.e., slows bleeding).  The polymer has biomedical and pharmaceutical applications and is useful for treating serious wounds.

Marine Polymer alleged that HemCon infringed claims 6, 7, 10, 11, 12, 17, and 20 of the patent.

Claim 6 of the patent recites:

A biocompatible [p-GlcNAc] comprising up to about 150,000 N-acetylglucosamine monosaccharides covalently attached in a ß-1?4 conformation and having a molecular weight of up to about 30 million daltons in which at least one N-acetylglucosamine monosaccharide has been deacetylated.

The only disputed claim term on appeal was “biocompatible.”  (The terms means that the  polymer was not highly reactive with living cells.)  Marine Polymer argued for a narrow construction of the term and the defendant argued for a broad construction.  The district court adopted a construction narrower than the one proposed by Marine Polymer, Marine Polymer moved for summary judgment of infringement, and the district court granted the motion. 

The issues of patent validity and infringement were then tried to a jury, which found the patent valid and awarded $29.4 million to Marine Polymer.

While the infringement case was pending, HemCon had filed a request with the USPTO for an ex-parte reexamination of the patent at issue.  During this reexamination, the patent examiner construed “biocompatible” more broadly than the district court had.  The USPTO also found claims to be obvious based on the prior art. 

Marine Polymer then cancelled the claims that were rendered obvious and argued that the examiner should adopt the district court’s narrower construction of “biocompatible.”  The patent examiner accepted this argument, and found all claims patentable based on that construction.

On appeal, HemCon argued that it had acquired intervening rights during the reexamination and thus was not an infringer.  A panel of the Federal Circuit agreed.

Marine Polymer argued that intervening rights can’t be acquired unless the claims have been amended or are new.  In this case, the key claims had not been amended and were not new.

Upon reconsideration en banc, the Federal Circuit affirmed the original judgment of the district court and reinstated the jury verdict.