Digest of In Re Hitachi Metals, Ltd.No. 2014-1689 (Fed. Cir. Mar. 17, 2015) (non-precedential). On appeal from the USPTO, Patent Trial and Appeal Board (“Board”). Before Prost, Plager and Wallach.

Procedural Posture: Hitachi appealed a decision of the Board rejecting certain claims of U.S. Patent No. 5,645,651 (“’651 patent”) for obviousness-type double patenting over claims of U.S. Patent No. 4,792,368 (“’368 patent”) in an ex parte reexamination. CAFC affirmed.

  • Claim Construction: The Board correctly construed the claims of the ’368 patent to include specific impurities in certain magnetic materials in view of the transitional phrase “consisting essentially of” and the disclosures in the specification.
  • Double Patenting: CAFC found that the only difference between the relevant claims in the ’368 patent and the ’651 patent was the addition of two elements in the ’651 claims, one from each of groups X and A. The Board correctly held that the ’651 claims and the ’368 claims were not patentably distinct because the compound claimed in the ’368 claims included the impurities that belonged to X and A groups.