One advantage of the AIA’s new post-grant proceedings over litigating patent validity in federal district court is that the USPTO currently gives claims in unexpired patents their broadest reasonable interpretation (BRI) in light of the specification, which frequently means that more potentially invalidating prior art may be used. The Office justifies the use of BRI for unexpired patents because, consistent with examination, the patent owner has an ability to amend claims. Office Patent Trial Practice Guide, 77 Fed. Reg. 48,756, 48,764 (Aug. 14, 2012).