Deutsche Bank analyst Brian Mullan initiated coverage of Shake Shack with a Hold rating and $90 price target. The stock closed Friday down $2.01 to $95.52. Shake Shack is a "truly differentiated brand" within the restaurant industry and has a "compelling" long-term growth opportunity, Mullan tells investors in a research note. However, with the shares up 115% year-to-date, the analyst thinks the market is pricing in a lot of the positive factors at this point in time. As such, he advocates patience and prefers to wait for a better entry point into Shake Shack shares.