(May 13, 2016, 9:02 AM EDT) -- ALEXANDRIA, Va. — Efforts by AT&T Mobility LLC to institute covered business method (CBM) review of four claims of a cellular telephone directory call assistance patent were unsuccessful on May 4, when the Patent Trial and Appeal Board (PTAB) denied the request (AT&T Mobility LLC v. Intellectual Ventures II LLC, No. CBM2015-00185, PTAB)....