How to Nullify a Patent

by Tom Streissguth

To protect an original invention, an individual or organization can file for a patent from the United States Patent and Trademark Office. A valid patent runs for 20 years; design patents run for 14. If you believe the government has issued a patent in error, or that a new patent infringes on your own, you have the right to ask for a reexamination of the patent. The process works through the USPTO, which is responsible for examining and granting patents. The procedure involves several steps, forms and documents, and also demands the payment of a fee.

Filing for Reexamination

Federal patent law allows anyone to file a request for reexamination with the USPTO, either by mail or electronically through the EFS-Web system. The USPTO rules provide for "ex parte" requests, which are available to anyone but limit participation by the requester and the original patent owner; an alternative would be filing a claim of patent infringement in federal court, which would involve much lengthier, and most costly, litigation. You must provide a Substantial New Question of Patentability, which is a statement of new information, not considered by the original examiner, which supports your case. Include a copy of the original patent and the application fee.

Prior Art

In any ex parte reexamination claim, the individual filing the request must base his claims on "prior art" or printed material. Prior art is material, such as a patent application or drawing, that supports a claim of infringement. Once the reexamination request is filed and then accepted by the USPTO, it may not be withdrawn.

Timeline and Appeals

For an ex parte examination, the USPTO rules call for a decision on the request for reexamination within three months from the date the request is made. If the agency approves the request for a reexamination, the requester may not amend the request to change its scope -- for example, to include a new claim, or to withdraw a claim already made. Once the process ends, the USPTO issues a reexamination certificate with its decision.

Inter Partes Review

The USPTO also makes a "post-grant" reexamination possible within nine months of the issuance of a new patent. After the nine-month window closes, the agency allows an "inter partes" review. An inter partes review must be based on prior art based on patents or publications, while a post-grant review can be based on any grounds the requester brings to the claim. If the USPTO rejects claims in the original patent application, the patent owner may submit new claims. If the agency rejects the original patent, the owner of the patent can appeal. If all appeals are denied, the patent is nullified.