Can a secret patent be used as prior art under 35 U.S.C. 102(a) or pre-AIA 35 U.S.C. 102(a) or (b)?

No, a secret patent cannot be used as prior art under 35 U.S.C. 102(a) or pre-AIA 35 U.S.C. 102(a) or (b). The MPEP 2126 states:

“Even if a patent grants an exclusionary right (is enforceable), it is not available as prior art under 35 U.S.C. 102(a) or pre-AIA 35 U.S.C. 102(a) or (b) if it is secret or private.”

This principle was established in the case of In re Carlson, where the court held that a document must be at least minimally available to the public to constitute prior art. Secret patents are defined as patents that are insufficiently accessible to the public to qualify as “printed publications.”

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Topics: (B), And (D), MPEP 2100 - Patentability, MPEP 2126 - Availability Of A Document As A "Patent" For Purposes Of Rejection Under 35 U.S.C. 102(A) Or Pre - Aia 35 U.S.C. 102(A), Patent Law, Patent Procedure
Tags: 35 U.S.C. 102(A), Pre-Aia 35 U.S.C. 102(A), Pre-Aia 35 U.S.C. 102(B), printed publications, Secret Patents