Mealey's (April 13, 2018, 9:36 AM EDT) -- WASHINGTON, D.C. — In an April 2 appellee brief, a patent owner defends a decision by the Patent Trial and Appeal Board (PTAB or board) that rejected allegations of obviousness by WhatsApp Inc. and Facebook Inc. (WhatsApp Inc., et al. v. TriPlay Inc., Nos. 17-2549, -2551, Fed. Cir.)....