Stephanie conceives of a compound (QED) in December 2011. She synthesizes the compound in February 2012. Entirely independently of Stephanie, Klay publishes an article in NATURE describing QED on December 1, 2012. Stephanie files a U.S. patent application on February 1, 2013. Assuming that Stephanie's invention is useful, non-obvious, and adequately described, is her patent valid or invalid based on these facts in the United States.