Jefferies analyst Brent Thill downgraded Trade Desk to Hold from Buy while raising his price target for the shares to $250 from $225. The stock closed Wednesday up 64c to $244.18. The valuation multiple at all-time highs may already reflect the bull case for the stock, Thill tells investors in a research note. The analyst, who admits to being a fan of the fundamental story, points out that Trade Desk shares are up five-fold from early 2018. The current valuation of 13.3 times estimated fiscal 2020 sales may already embed further upside, Thill contends. He views connected TV and international expansion as the next legs of Trade Desk's growth, but feels these initiatives may not drive estimates high enough to justify a higher valuation.