Anyone other than the Patent Owner may request cancellation as unpatentable one or more claims of a U.S. patent in an Inter Partes Review proceeding. The America Invents Act, in 35 U.S.C. Section 311(b), provides that an IPR Petitioner may challenge patentability "only on a ground that could be raised under section [35 U.S.C Section] 102 (anticipation) or 103 (obviousness) and only on the basis of prior art consisting of patents or printed publications." In a Decision issued in Hulu, LLC v. Sound View Innovations, LLC, IPR2018-01039 (PTAB Dec. 20, 2019), the Precedential Opinion Panel of the USPTO's Patent Trial and Appeal Board has confirmed that an IPR Petitioner should preferentially base its patentability challenge on patents, rather than printed publications, whenever possible - even though the AIA makes no distinction between the two categories of prior art.