On September 16, 2011, President Obama signed the America Invents Act.
On March 16, 2013, the third and final wave of provisions of the America Invents Act (AIA) became effective. This completes the overhaul of the U.S. patent law that began with the enactment of the AIA on September 16, 2011. The United States will move to a first-to-file system with these provisions. It will greatly expand the definition of prior art and usher in the use of post grant review.