Marathon Petroleum (MPC -3.4%) slides after Citigroup cut the shares to Neutral on valuation...

|About: Marathon Petroleum Corp. (MPC)|By:, SA News Editor

Marathon Petroleum (MPC -3.4%) slides after Citigroup cut the shares to Neutral on valuation earlier this morning. The stock's been a solid performer this year, having charged 52% higher just since mid-June.