The majority owners of the Boston Celtics are celebrating the team's latest championship by putting the Celtics on the market. Shares owned by a group led by entrepreneur Wyc Grousbeck are now for sale, reports WCVB. Grousbeck's group paid $360 million for a majority stake in the team back in 2002, but buyers today better be prepared for a much higher price. ESPN notes that controlling shares in the Phoenix Suns, Milwaukee Bucks, and Dallas Mavericks have gone for $4 billion, $3.5 billion, and $3.5 billion, respectively, in the last two years.