Summary: Here is everything you must know before Friday's opening bell: AT&T and Novartis continue to try to save face as the Michael Cohen story widens. Cisco Systems announced that it is pulling all online ads from YouTube . JPMorgan Chase is reportedly planning to completely revamp its stock trading business with an overhaul to its management team. Nvidia revealed details that indicate an increasing reliance on volatile cryptocurrency mining activity. U.S. stock futures were trading mixed.
