CAFC Decides Patent Reissue was Improperly Broadened Based on Previous Markman Definition

Yesterday, in ArcelorMittal France v. AK Steel Corp.(CAFC 2015), the CAFC considered the impact of a reissue of U.S. Patent 6,296,805 on a previous appeal decision.  The '805 patent, directed to rolled steel, recited the claim limitation "very high mechanical resistance."  In an earlier infringement suit between the parties, the district court found this terminology to define "a tensile strength greater than 1500 MPa." This construction was upheld by the CAFC on appeal, and the case as remanded as to other issues.  

During the appeal of the claim construction, Patentee reissued the '805 patent as reissue patent RE44,153.  The reissue patent included a new claim, claim 23, that recited "mechanical resistance in excess of 1000MPa."  The originally construed claims remained in the reissue patent. Once back in the district court, Patentee amended its complaint to include claim 23 of the new reissue patent.  Thereafter, on summary judgement, the district court ruled the reissue patent invalid for improper broadening. In the second appeal, decided yesterday, the CAFC agreed that claim 23 of the '153 reissue was improperly broadened.  

Ostensibly, the USPTO did not consider 1000MPa limitation as broadening relative to the specification of the '805 patent.  On the other hand, the CAFC found  "greater than 1000MPa" to be broadening based upon the district court's previous construction that the scope of "very high mechanical resistance" was greater than 1500MPa. This difference in construction highlights the potential incongruity between USPTO and district court claim construction practices.

At the heart of the CAFC's affirmance was the continued distaste for collateral attacks on previous judgments.  The Court explained that the "law of the case doctrine" prevents deviation from the decision of a prior appeal (i.e., claim construction) absent extraordinary circumstances tied to "new evidence"  — the CAFC did not find the patent reissue to constitute such.

The successful prosecution of the RE153 patent is not “new evidence” sufficient to trigger the extraordinary circumstances exception to the mandate rule and the law of-the-case doctrine. Permitting a reissue patent to disturb a previous claim construction of the original claims would turn the validity analysis under 35 U.S.C. § 251 on its head. The basic inquiry under § 251 requires comparing the scope of the claims of the reissue patent to the scope of the original claims to determine if the reissue patent “contains within its scope any conceivable apparatus or process which would not have infringed the original patent.” Tillotson, Ltd. v. Walbro Corp., 831 F.2d 1033, 1037 n.2, 1039 (Fed. Cir. 1987). If the reissue claim itself could be used to redefine the scope of the original claim, this comparison would be meaningless.

Note, the reissue that was pursued was not a "broadening reissue," which is only possible if pursued within two years of original patent issuance. Instead, the '153 reissue was a narrowing reissue. Presumably the former would constitute new evidence under the law-of-the-case doctrine.

It is well established that a claim is considered to be broadening if the patent owner would be able to sue any party for infringement who previously could not have been sued for infringement. In this case, given the court's earlier construction, if the defendant did not make steel of a strength greater than 1500MPA, claims that expanded the range down to 1000MPA would clearly permit a new infringement charge (assuming the defendant made steel with a strength of 1000MPa or greater).  On the other hand, if the baseline construction of the USPTO were applied, the broadening determination outcome in this case would have been different. 

Markman constructions may be considered by the USPTO, but are not binding on the agency. In re Trans Texas Holdings Corp., 498 F.3d 1290 (Fed. Cir. 2007).  However in this case, one might argue that the since the claims had been assessed by the courts as to infringement scope, regardless of any PTO analysis to the contrary, the court construction was of heightened importance from a public policy perspective.

All that said, since the original claims did not recite a numerical range at all, the examiner may have just missed the issue altogether. This is because, absent the history of the litigation (which was filed), the claims would seem to be narrowing to the naked eye. it is worth noting that there were no substantive rejections of the claims during reissue examination. More recently, reissue applications have been moved from the general examining corps to the to the Central Reexamination Unit (CRU).