Today's biggest winners and losers in the stock market.

On this episode of Stock Movers:

- 3M (MMM) is now lower even though it reaffirmed its full-year guidance, betting that rebounding demand for industrial products and office supplies will outweigh one-off charges that squeezed its first-quarter bottom line.

- UnitedHealth Group (UNH) share are rallying after the health insurer boosted its adjusted earnings per share forecast for the full year. Its first quarter profits also beat Wall Street’s expectations.

- Tractor Supply (TSCO) slipped after the rural lifestyle retailer reported comparable sales for the first quarter that missed the average analyst estimate. Management reaffirmed their annual forecasts.