In In re Berger, 279 F.3d 975 (Fed.Cir.2002), the Court applied 35 U.S.C. section 135(b)(1) and explained its implications. In Berger, the appellant had copied a claim from the Muller patent more than one year after that patent had issued, amending his application to add the copied claim as new claim 7. 279 F.3d at 978. The Board affirmed the examiner's rejection of claim 7 under section 135(b).1 The Board explained that the rejected claim contained material differences from claims 1-6, which were on file before the critical date. Id. at 980. On appeal, this court assessed the correctness of the Board's test to determine whether the earlier claims 1-6 supported claim 7. Id. at 981-82. Following Corbett v. Chisholm, 568 F.2d 759 (CCPA 1977), the Court explained that "to establish entitlement to the earlier effective date of existing claims for purposes of the one-year bar of 35 U.S.C. 135(b), a party must show that the later filed claim does not differ from an earlier claim in any `material limitation.'" Berger, 279 F.3d at 981-82 (quoting Corbett, 568 F.2d at 765-66).