Patent Reexamination

Patent reexamination is a procedure whereby the validity of an issued patent may be reexamined by the United States Patent and Trademark Office.  Any patent owner or third party may request the reexamination of a patent based on a “substantial new question of patentability.”  When a substantial new question of patentability is raised in a request for reexamination, the United States Patent and Trademark Office reopens the examination of the patent, providing one or more new claim objections or rejections and allowing the patent owner/applicant to amend the issued claims to overcome the new questions of patentability.

Patent reexamination is becoming an increasingly popular litigation strategy, both by plaintiffs and defendants.  A patent owner may request reexamination in an effort to clean up any potential validity issues prior to filing a claim for patent infringement.  When accused with infringement, an accused infringer may request patent reexamination to attack the allegedly infringed patent.  Reexamination may be used to stay patent litigation, provide a potentially more favorable forum for infringement defendants and is typically significantly less expensive than patent litigation.

There are two patent reexamination mechanisms available through the United States Patent and Trademark Office; ex parte patent reexamination and inter partes patent reexamination.  The main differences between the two mechanisms are (1) the level of involvement in the process by the reexamination requester and (2) the cost.

In ex parte reexamination, the requester merely pays the required fee and submits a detailed request for reexamination.  From that point forward, the requester is no longer involved in the process.

In inter partes reexamination, the requester is given the opportunity to respond to each of the responses filed by the patent owner.  Additionally, inter partes reexamination creates an estoppel against the participating party, preventing the participating party from challenging the patent on the reexamined issues during litigation.

If you would like to speak with an experienced patent attorney about any patent reexamination maters, contact me for a free consultation.