The article discusses the implications of the Leahy-Smith America Invents Act (AIA) for the U.S. patent system and the biotechnology industry. It notes that the conversion from a first-to-invent system to a first-to-file system is the most important provision of AIA. There are key revisions to the criteria for prior art under the first-to-file system of AIA. Information on exceptions to the prior art criteria is provided.