JPMorgan analyst Jeffrey Zekauskas downgraded Cabot (CBT) to Underweight from Neutral with an unchanged price target of $105. The firm expects prices for carbon black in the U.S. to flatten out after a multi-year period of increase. Cabot is trading at a 3-3.5 times multiple point premium to Orion, the analyst tells investors in a research note. JPMorgan cites relative valuation for the downgrade of Cabot.