Snap shares jump after Wall Street analyst gives thumbs up

Snap's shares jumped 12 percent Thursday, reaching a six-month high after a high-profile upgrade from a Wall Street analyst. BTIG's well-known Snap bear Rich Greenfield changed his recommendation from "neutral" to "buy" and upgraded his price target from $5 to a Street-leading $15 -- representing what would be a 50 percent increase from the stock's...