The America Invents Act (AIA) has given defendants in patent cases new weapons that can be particularly effective for battling vexatious trolls. The AIA created new trial-like proceedings—Inter Partes Review (IPR), Covered Business Method Review (CBM), and Post-Grant Review (PGR)—in which to challenge the validity of patents before the Patent Trial and Appeal Board (PTAB). The popularity of these “AIA trials” is undeniable; more than 3,500 petitions to institute AIA trials have been filed since the proceedings launched September 16, 2012.