Refiners Awash in Shale Oil Offer 10 Times Exxon Returns

Refiners Awash in Shale Oil Offer 10 Times Exxon Returns

Eddie Seal/Bloomberg

Valero and Marathon Petroleum Corp. are among refiners whose discount to stocks in an S&P 500 index of 45 energy companies have narrowed this year, showing that investors have growing confidence that their earnings will rise.