UBS's Big Oil Call: Downgrades Chesapeake, Murphy; Upgrades Marathon By: Benzinga via Benzinga June 25, 2015 at 11:02 AM EDT In a report published Thursday, UBS analyst William A. Featherston changed the ratings on three oil majors, having raised the 2015-16 ... Read More >> Related Stocks: Chesapeake Energy Marathon Oil Murphy Oil UBS Group Ag ADR