 At the time, this was the largest real estate stock offering ever made.In 1996, the company merged with the DeBartolo Realty Corporation in a $3.0 billion merger becoming the Simon DeBartolo Group.In 1998, the company reverted to the Simon Property Group name and maintains its title as the largest mall operator in the United States, owning 386 properties in North America, Europe and Asia; clocking 2.8 billion shopper visits each year, and having annual sales in excess of $60 billion.