The proceedings created by the America Invents Act, which first became available in September 2012, have had a significant impact on the US patent landscape, particularly how, and whether, parties litigate patent disputes. These post-grant proceedings—inter partes review (IPR), post-grant review, covered business method review (collectively, PGRs)—provide accused infringers with the opportunity to seek review of an asserted patent’s validity at the US Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB). By October 31, 2015, more than 4,000 petitions seeking PGR, the vast majority seeking IPR, had been filed.