Jefferies analyst Brent Thill raised the firm's price target on Dropbox to $21 from $19 and keeps a Hold rating on the shares. The company reported Q4 revenue ahead of expectations but billings slightly missed estimates and net new paid user adds declined quarter-over-quarter, Thill tells investors in a post-earnings research note. The analyst says Dropbox's lack of growth catalysts keep him at a Hold rating. The biggest surprise in the quarter was the long-term operating margin guidance of 28%-30%, up from 20%-22%, says the analyst, who notes he remains cognizant of the balance between growth and profitability.