Roku stock falls after Stephens downgrades on concern that even the bears are upbeat

Roku Inc. shares are falling in premarket trading Tuesday after Stephens analyst Kyle Evans downgraded the stock to equal weight from overweight, writing that the shares now look riskier following a big rally. Roku shares are up more than 200% so far this year. "The simple math on current Roku estimates is that the lowest sell-side ratings/targets have the highest estimates, and most hold/sell analysts now have 2Q19 estimates above consensus and 2019 estimates above company guidance," Evans wrote. "While this setup isn't rare, we do believe it creates real near-term risk for Roku given its current valuation and historical volatility." The stock is off 0.9% in premarket trading Tuesday. It's gained 51% over the past month, as the S&P 500 has dropped 3.9%.

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