Reissue Claims That Broaden Scope of Original Claims in View of Prior Claim Construction Held Invalid

In ArcelorMittal France v. AK Steel Corp., No. 14-1189 (Fed. Cir. May 12, 2015), the Federal Circuit affirmed the district court’s finding that certain claims of U.S. Patent No. RE44,153E (“the RE153 patent”) were invalid as impermissibly broadened, but reversed the district court’s determination of invalidity with respect to other claims that were not broadened.

The RE153 patent is a reissue of U.S. Patent No. 6,296,805 (“the ’805 patent”). In a previous appeal regarding the ’805 patent, the Federal Circuit affirmed the district court’s construction of a claim term and remanded the case. While that appeal was pending, ArcelorMittal sought to correct that construction through a reissue application, which led to the RE153 patent. On remand, ArcelorMittal substituted the ’805 patent for the RE153 patent. The district court granted summary judgment that all claims of the RE153 patent were invalid.

In the present appeal, the Federal Circuit held that the law-of-the-case doctrine prohibited the district court from revisiting its original construction; thus, it affirmed the district court’s finding that claims that were broadened in view of that construction were invalid. The Court also noted, however, that invalidity based on impermissible broadening must be analyzed on a claim-by-claim basis. Accordingly, the Court held that the district court erred in invalidating two claims that did not broaden the scope of the original claims.