Novelty. This is because the United States Patent and Trademark Office (USPTO) has to identify all of the claimed elements within the four corners of a single reference. By contrast, in order to make an obviousness rejection, the USPTO is allowed to combine multiple references together. In the past, the USPTO could only combine references together if there was a "teaching, suggestion, or motivation" to combine them as such. However, after KSR Int'l Co., v. Teleflex Inc. (2007), the U.S. Supreme Court ruled that a person skilled in the art is "creative" and has "common sense" and therefore would not necessarily need to have an explicit teaching, suggestion, or motivation to combine the references.