In only their fourth precedential decision of 2009, the Board of Patent Appeals and Interferences (BPAI) in Ex Parte Tanaka (December 9, 2009, Appeal No. 2009-000234) considered permissible bases under 35 U.S.C. § 251 for a patent to be eligible for reissue. This decision by an expanded panel expressly overturns any contrary precedent that allowed reissue based on a submission of one or more narrower claims as a hedge against potential invalidity of the issued claims. A reissue application must satisfy § 251, which requires that through error without deceptive intent, a patent be wholly or partly inoperative or invalid because of defects in the specification or drawings or because the patentee claimed more or less than he is entitled to. The BPAI held that merely submitting a narrower claim to hedge against possible invalidity of the original claims, without particularly identifying any inoperability or invalidity of any of the issued claims, is not sufficient grounds for reissue. In light of this decision, patent practitioners considering reissue should carefully evaluate whether their bases for reissue satisfy the requirements of § 251.
A copy of the Tanaka opinion can be found on the USPTO website at the following link.