Inter Partes Review (IPR)

What It Means

Inter partes review (IPR) is an administrative trial conducted by the Patent Trial and Appeal Board (PTAB) at the USPTO to re-examine whether a granted patent should have been issued. Introduced by the America Invents Act of 2011, IPR provides a faster and cheaper alternative to challenging patent validity in federal court. Any person or entity (other than the patent owner) can petition for IPR, but the petition must be filed within one year of the petitioner being served with a patent infringement complaint. An IPR can only challenge patents on grounds of novelty and non-obviousness, using only patents and printed publications as prior art. The PTAB decides whether to institute the review based on whether the petitioner demonstrates a reasonable likelihood of prevailing on at least one challenged claim. If instituted, the proceeding follows a trial-like format with discovery, expert declarations, and oral argument, and must be completed within 12-18 months. IPR has become a powerful tool for companies facing patent infringement suits, particularly from NPEs (patent trolls). Statistically, IPR is highly effective at invalidating patent claims — historically, when the PTAB institutes review, claims are cancelled or narrowed in approximately 60-70% of cases. This success rate has made IPR a first line of defense for many technology companies. However, critics argue that IPR makes it too easy to invalidate patents that went through rigorous prosecution, creating uncertainty for patent holders. The availability of IPR affects patent portfolio valuation because patents that have survived IPR challenges are considered stronger and more defensible than untested patents.

Frequently Asked Questions