What is the rationale behind the ‘all or nothing’ approach to patent unenforceability?

The ‘all or nothing’ approach to patent unenforceability due to inequitable conduct is based on the principle that such misconduct affects the entire patent right. MPEP 2016 cites the Gemveto Jewelry Co. v. Lambert Bros., Inc. case, which explains:

“The gravamen of the fraud defense is that the patentee has failed to discharge his duty of dealing with the examiner in a manner free from the taint of ‘fraud or other inequitable conduct.’ … It is an all or nothing proposition.”

This rationale emphasizes that the duty of candor applies to the entire patent prosecution process, not just individual claims.

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Topics: Inequitable Conduct, MPEP 2000 - Duty Of Disclosure, MPEP 2016 - Fraud, Or Violation Of Duty Of Disclosure Affects All Claims, Patent Law, Patent Procedure
Tags: All Or Nothing, Duty Of Candor, inequitable conduct, patent unenforceability