Shares of Snapchat parent Snap Inc. SNAP, +9.80% shot up 9.7% toward a 6 1/2-month high in active morning trade Thursday, after BTIG analyst Richard Greenfield surprised his followers by turning bullish on the social media company, citing among other reasons a surge in advertising spend and user stickiness. Greenfield raised his rating to buy, after being at neutral for three months, which followed a 3-month stretch at a sell rating. He set a $15 stock price target, which is 25% above current levels. “Your initial reaction is likely why now and what changed, as virtually everything that could go wrong for Snapchat over the past couple years since going public as gone wrong,” Greenfield wrote in a note to clients. He gave 5 reasons for the upgrade: performance advertising growth, discover sector feels less seedy, user stickiness, out mushroom rebuild testing is positive and new management/morale. The stock has doubled year-to-date, but was still down 38% over the past 12 months. In comparison, the S&P 500 SPX, -0.12% has climbed 12% this year and gained 2.1% the past 12 months.

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