On Sept. 16, 2011, President Barack Obama signed the America Invents Act into law. The AIA created the most extensive changes to U.S. patent law in decades. It contains a number of provisions that went into effect at different times so the changes would not be so overwhelming.
One year later, on Sept. 16, 2012, new procedures became available under the AIA for third parties to challenge the validity of someone else's patent at the U.S. Patent and Trademark Office. This article focuses on two of these new post-grant proceedings: inter partes review (IPR) and post-grant review (PGR). IPR is available for all patents. PGR is only available for patents that were filed last year; those will start issuing next year.