In 2011, President Obama signed the America Invents Act which made substantial changes to the U.S. patent system. Effective 16 Mar 2013, only the “first-to-file” inventor had priority, eliminating claims by others of being the first to invent an invention. “Prior art,” used to exclude patentability, was expanded to include public use, sales including foreign offers for sale, publications and disclosures available to the public anywhere in the world as of date of filing. Previously, for example, when William Kelly asserted he was first to invent his “air-boiling” process to refine steel, he was awarded U.S. patent priority (23 Jun 1857) over Henry Bessemer, even though Bessemer filed first.«