Can collateral estoppel apply in patent reexamination proceedings?

Collateral estoppel, or issue preclusion, can apply in certain circumstances during patent reexamination proceedings. According to MPEP § 2259: “If the claims in a reexamination proceeding present the same issue(s) as claims that were finally held invalid by a federal court in a proceeding involving a different patent in the same patent family, collateral estoppel…

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