Shares of Snap Inc. /zigman2/quotes/205087158/composite SNAP -0.10% are up more than 6% in premarket trading Friday after Wells Fargo analyst Brian Fitzgerald upgraded the stock to overweight from equal weight. "We don't expect Snap to be immune from COVID-19 impacts on ad budgets, though Snap's strong direct response momentum, limited [small- and medium-sized business] exposure and lower international exposure could insulate Snap somewhat relative to peers," he wrote. Fitzgerald said that Snap's stock has underperformed the S&P 500 /zigman2/quotes/210599714/realtime SPX +1.36% in recent weeks, falling 51% since the lockdown in Wuhan began in late January, compared with a 28% drop for the S&P in that span. That creates "an attractive entry point for long-term holders," in Fitzgerald's view, even though he concedes that trading could be choppy in the weeks that follow. He lowered his price target to $14 from $20 in conjunction with the upgrade.