Post-Grant Opposition: A Proposal and a Comparison to the America Invents Act

33 Pages Posted: 14 Mar 2011 Last revised: 11 Mar 2013

Date Written: September 21, 2011


The patent system is designed to promote innovation. But the U.S. Patent and Trademark Office (“PTO”) cannot devote the resources necessary to grant only valid patents. This Article explores one mechanism to address this challenge: a post-grant opposition procedure that would allow any party to challenge a patent after it is issued. It explains why such a system is superior to other alternatives, such as improved PTO review, litigation, or reexamination.

An opposition system offers numerous benefits. It targets the most valuable patents, increases access to competitors’ information, reduces the number of invalid patents, and provides a quicker and cheaper determination of validity than litigation. In the deluge of patent applications confronting the PTO in the 21st century, an effective post-grant opposition system promises to promote innovation.

Shortly before this Article went to press, Congress had passed the America Invents Act, patent reform legislation that included a post-grant opposition procedure. This Article offers a preferred opposition regime that serves as a counterpoint to the system the legislature enacted.

The elements of the opposition process determine whether it will be fair to patentees and challengers. As a result, this Article sets forth numerous details of my proposed opposition system, including (1) the threshold a challenger must clear to commence an opposition, (2) the timing of the process, (3) the grounds on which a patent can be challenged, (4) the nature of the required evidentiary showing, (5) the procedure’s judges and appeals, (6) the materials that can be introduced in the proceeding, (7) the disclosure of the requester’s identity, and (8) the preclusive effect of an opposition. In particular, this Article critiques the provisions of the America Invents Act that address the threshold showing a challenger must make, the timing within which a challenger must file, the disclosure of the real party in interest, and estoppel.

Keywords: patents, patent reform, post-grant opposition, America Invents Act

JEL Classification: O34, O31, K11

Suggested Citation

Carrier, Michael A., Post-Grant Opposition: A Proposal and a Comparison to the America Invents Act (September 21, 2011). UC Davis Law Review, Vol. 45 (2011), Available at SSRN:

Michael A. Carrier (Contact Author)

Rutgers Law School ( email )

217 North Fifth Street
Camden, NJ 08102-1203
United States
856-225-6380 (Phone)
856-225-6516 (Fax)

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