Mizuho analyst Gregg Moskowitz downgraded ServiceNow (NOW) to Neutral from Buy with a price target of $230, down from $308. The stock in premarket trading is down 10%, or $21.84, to $206.50. The company last night surprisingly announced the impending departure of CEO John Donahoe, who is going to head Nike (NKE), and lowered its full year guidance due to currency, Moskowitz tells investors in a research note. Employee attrition has also become a concern, says the analyst, who worries that the departure of Donahoe “could accelerate this trend.” As a result, he prefers to move to the sidelines with the respect to the shares.