By Kelly Eberspecher and Katherine Cappaert (March 21, 2018, 12:46 PM EDT) -- 35 U.S.C. § 325(d) provides that "[i]n determining whether to institute or order a proceeding . . the Director may take into account whether, and reject the petition or request because, the same or substantially the same prior art or arguments previously were presented to the Office." 37 C.F.R. § 42.4(a) delegates this discretion to the board. Thus, 325(d) often presents a separate and threshold hurdle that a petitioner must confront when seeking institution of trial for a given patent. For the responding patent owner, 325(d) provides an opportunity to convince the board that the petitioner's arguments (and art) are simply a rehash of what was reviewed and considered by the U.S. Patent and Trademark Office....