Shares of Madison Square Garden Co. are up more than 10% in premarket trading after the company said it received board approval to explore the possibility of spinning off its sports businesses into a separate company. Jefferies analyst John Janedis upgraded the stock to buy from hold on Thursday, raising his price target to $350 from $233. "MSG possesses a collection of unique, world class sports and entertainment assets which are largely underappreciated by investors," Janedis wrote. "As MSG intends to separate the Sports and Entertainment businesses in a tax-free spin, we expect the discount to fair value to narrow and shares to better reflect the considerable intrinsic value of the assets." MSG shares were up 33% over the past 12 months, as of Wednesday's close, while the S&P 500 had gained 11%.