Take a look at some of the biggest movers in the premarket:Ford (F), General Motors (GM) – UBS downgraded both automakers, cutting Ford to "sell" from "neutral" and downgrading GM to "neutral" from "buy." Ford slid 3.6% in the premarket while GM fell 3.5%. Rivian (RIVN) – Rivian shares tumbled 9% in the premarket after it recalled nearly all its vehicles to fix potential steering issues. Kraft Heinz (KHC) – Kraft Heinz rose 2% in premarket action after Goldman Sachs upgraded the food maker's stock to "buy" from "neutral." Merck (MRK) – Merck rose 2.7% in the premarket after Guggenheim upgraded the stock to "buy" from "neutral."

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