The America Invents Act (AIA) overhauled several aspects of patent law, including establishing a new threshold for requesting inter partes reexamination.  Under the prior patent laws, inter partes reexamination of a patent was granted only upon a showing of a substantial new question of patentability (SNQ) for at least one patent claim.  Effective upon enactment of the AIA, however, this threshold has changed.  The new threshold requires a petitioner to show that the information in its request establishes a reasonable likelihood that the petitioner will prevail with respect to at least one patent claim.  This new threshold applies only to requests for inter partes reexamination filed on or after September 16, 2011, and the SNQ standard will apply to all earlier requests to the conclusion of those proceedings.  As the new “reasonable likelihood of prevailing” threshold appears to be a higher standard, the USPTO may now not grant a request for inter partes reexamination where it may have in the past.  Thus, prior to filing a request for inter partes reexamination, third parties should carefully consider the various options for challenging a patent relative to the newly instituted threshold.