What is the purpose of citing prior art in patent files?

The main purpose of citing prior art in patent files is to inform relevant parties about the existence of patents or printed publications that may affect the validity of patent claims. According to MPEP 2202:

The basic purpose for citing prior art in patent files is to inform the patent owner and the public in general that such patents or printed publications are in existence and should be considered when evaluating the validity of the patent claims.

This practice helps ensure that all relevant information is available for consideration during any subsequent patent proceedings, such as reissue applications, reexamination proceedings, or other post-patent proceedings.

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Topics: MPEP 2200 - Citation Of Prior Art And Ex Parte Reexamination Of Patents, MPEP 2202 - Citation Of Prior Art And Written Statements, Patent Law, Patent Procedure
Tags: Citation Purpose, patent files, patent validity