A Recent Clarification on Intervening Rights by the Federal Circuit
The Federal Circuit recently found that intervening rights can apply to a claim that has been narrowed by argument only during a reexamination.
In Marine Polymer Technologies, Inc. v. HemCon, the Federal Circuit recently found that narrowing a claim by argument only changes the substantive scope of the claim for purposes of intervening rights. Specifically, a claim term that is changed during reexamination without changing a word in the claim can still substantively narrow the scope of a claim. Therefore, upon reissue of the patent, an infringer would have “… absolute intervening rights with respect to products manufactured before the date of reissue.”
Marine Polymer alleged infringement of certain claims of its U.S. Patent No. 6,864,245 (the “’245 Patent”). During the district court Markman proceedings, the definition of only one claim term, biocompatible p-GlcNAc, was in dispute. The term “biocompatible” appears in every claim of the ’245 Patent. Both plaintiff and defendant proposed term constructions. The District Court reject their proposals and adopted its own, concluding that biocompatible p-GlcNAc meant “polymers… with low variability, high purity, and no detectable biological reactivity as determined by biocompatibility tests.” Based on this claim construction, the district court granted summary judgment of literal infringement for all of the seven asserted claims.
During the pendency of the district court proceedings, HemCon requested reexamination of the ’245 Patent with the United States Patent and Trademark Office (“PTO”). The examiner, in rejecting all of the claims, initially adopted a different claim construction than that of the district court. The examiner also determined “biocompatible” meant “low variability, high purity, and little or no detectable reactivity.” Further, the examiner noted that the district court’s construction was inconsistent with the numerous dependent claims that required a specific elution test score of zero, one or two.
Marine Polymer argued that the district court’s interpretation should be adopted and “biocompatible” should be construed to mean “no detectable biological reactivity.” Marine Polymer then cancelled the six original dependent claims that had specifically required an elution test score of 1 or 2. The language of the remaining claims, including all of the claims HemCon had been found to infringe by the district court, was unchanged.
Intervening rights do not apply where the accused product “infringes a valid claim of the reissued patent which was in the original patent.” 35 U.S.C. § 252. Therefore, intervening rights are available only if the original claims have been substantively changed, and in determining whether substantive changes have been made, the court must discern whether the scope of the claims has changed, not merely whether different words are used.
The Federal Circuit found that in narrowing the definition of “biocompatible” by argument, all of the remaining claims of the ’245 Patent had been substantively narrowed thereby substantially changing the scope of the claims. The Federal Circuit therefore determined that absolute intervening rights under the statute applied in this case. The specific products made before the date of reissue, which infringed the new reissue claims, were absolutely free of the reissued patent and may be used or sold after the date of the reissue without regard to the patent.
Under the Patent Statute, there are two types of intervening rights: (1) absolute intervening rights, which bar claims for infringement based on specific products that were manufactured before the reissue or reexamination; and (2) equitable intervening rights, which bar claims for infringement for new products and newly manufactured versions of prior existing products made after the reissue or reexamination. See 35 U.S.C. §§ 252, 307.
The Federal Circuit remanded to the District Court to determine whether the fact based doctrine of equitable intervening rights applies. The doctrine of equitable intervening rights allows the court to permit the continued manufacture, use, or sale of additional products covered by the reissued or reexamined patent when the accused infringer made, purchased, or used identical products before the reissue or reexamination date. It also protects a newly created product that was not of a type produced before the reexamination if the accused infringer made substantial preparations for manufacture of the product before the reissue or reexamination.