Warren Buffett's Berkshire Hathaway revealed a new 6.72billioninvestmentininsurancefirmChubbinaregulatoryfilingonWednesday,whichpropelledthecompany′sstocktoanall−timehigh.Berkshireowned25.92millionsharesinChubbasofMarch31,accordingtoaregulatoryfilingthatdetailsBerkshire′sU.S.−listedholdingsasofthatdate.Chubb′sstock,whichedgedslightlylowerby0.13271.96 a share as of We ...