Simon has sold or spun off many of its smaller shopping malls to concentrate on a handful of large properties that it hopes serious shoppers will see as day-long destinations. The company also controls the giant King of Prussia shopping complex, one of the largest on the East Coast, where it is connecting the Plaza and Mall through a corridor of new stores; the Philadelphia Premium Outlets at Limerick, Montgomery County, and South Jersey's Gloucester Premium Outlets, where construction started last month; plus Montgomery Mall, among other area properties.