Does listing a reference in an Information Disclosure Statement (IDS) constitute an admission of prior art?

No, merely listing a reference in an Information Disclosure Statement (IDS) is not considered an admission that the reference is prior art against the claims. According to MPEP 2129:

“Mere listing of a reference in an information disclosure statement is not taken as an admission that the reference is prior art against the claims.”

This is further supported by 37 CFR 1.97(h), which states: “The filing of an information disclosure statement shall not be construed to be an admission that the information cited in the statement is, or is considered to be, material to patentability as defined in § 1.56(b).”

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Topics: MPEP 2100 - Patentability, MPEP 2129 - Admissions As Prior Art, Patent Law, Patent Procedure
Tags: Ids, Information Disclosure Statement, patent procedure