US patents have been challenged by inter partes review (IPR) at the US Patent Trial and Appeal Board (PTAB) at an increasing rate since their creation by the America Invents Act in 2011. Patent owners often point to the ‘commercial success’ of the products covered by their patent as an indication that their patent is non-obvious. Non-obviousness is a legal requirement for the patent owner to maintain its patent rights. The showing of ‘commercial success’ to fight off a challenger’s claim of patent invalidity is an approach that has been taken by patentees for decades in district court litigations.