By James R. Klaiber 1
Patent reexamination is already a tricky process. For accused infringers, the decision to seek reexamination is sensitive because the asserted patent may be stronger if a reexamination certificate issues. For patent owners, reexamination face the risk of cancellation, as well as resulting in the de facto delay of any assertion efforts.
The Federal Circuit’s recent Southwestern Bell Telephone Co. v. Arthur A. Collins, Inc. decision2 adds a new wrinkle to the law of reexamination. It has been more than a decade since the Federal Circuit first held that a reexamination amendment that fails to comply with the requirements of the reexamination statutes results in the invalidity of the affected claim.3 In most such situations, the claim is pronounced invalid because it conflicts with the statutory prohibition on “enlarging the scope” of claims prosecuted during reexamination.4 But the Federal Circuit’s unpublished Southwestern Bell II decision held, for the first time, that claims added for an “improper purpose” can be invalidated in later litigation even if they are not impermissibly broadened and were not challenged by the U.S. Patent and Trademark Office during reexami...
