June 2020
Lexis Practice Advisor
By Thomas Lee Irving; Stacy Lewis*
This practice note teaches patent prosecutors how to overcome a patent examiner’s obviousness rejection by attacking the examiner’s prima facie case. Obviousness is one of the grounds for rejection of a patent application that is most frequently asserted by the U.S. Patent and Trademark Office (USPTO). Accordingly, knowing how to attack the examiner’s prima facie case is an essential patent prosecution skill. If you successfully attack the prima facie case, rather than rebutting it, you may avoid amending the claims and the resultant possibility of prosecution history estoppel that may later limit your client’s ability to rely on the doctrine of equivalents to prove infringement of its patent.
We discuss how to attack the prima facie case of obviousness in the context of the examination of patent application claims by a patent examiner. Note that the same principles apply in the context of inter partes patentability challenges before the USPTO’s Patent Trial and Appeal Board (PTAB), because the claims do not have a presumption of validity before the PTAB. However, in PTAB proceedings, the initial burden of persuasion is on the petitioner, the rebuttal burden is on the patent owner, and PTAB operates as an adjudicator of the parties’ arguments.
Read the full article here.
*Stacy Lewis is a Law Clerk at Finnegan
Originally printed in Lexis Practice Advisor in September 2019. This article is for informational purposes, is not intended to constitute legal advice, and may be considered advertising under applicable state laws. This article is only the opinion of the authors and is not attributable to Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, or the firm's clients.
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