How are claims construed in ex parte reexamination?

In ex parte reexamination, claims are given the broadest reasonable interpretation consistent with the specification. The MPEP states:

“During reexamination ordered under 35 U.S.C. 304, and also during reexamination ordered under 35 U.S.C. 257, claims are given the broadest reasonable interpretation consistent with the specification and limitations in the specification are not read into the claims (In re Yamamoto, 740 F.2d 1569, 222 USPQ 934 (Fed. Cir. 1984)).”

However, for expired patents, claim construction follows the principle set forth in Phillips v. AWH Corp., where claims are given their ordinary and customary meaning as understood by a person of ordinary skill in the art at the time of the invention.

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Topics: MPEP 2200 - Citation Of Prior Art And Ex Parte Reexamination Of Patents, MPEP 2258 - Scope Of Ex Parte Reexamination, Patent Law, Patent Procedure
Tags: broadest reasonable interpretation, Claim Construction, ex parte reexamination, Expired Patents