After seeing the potential of the single mall in Puerto Rico, Lichtenstein made his first major deal in the real estate market in 2003. He purchased the entire Prime Retail portfolio for $638 million. The portfolio consisted of 37 properties spread across a number of states in the US, in locations such as Pleasant Prairie, Wis., Odessa, Mo., and Gaffney, S.C. The acquisition made Lightstone the second-largest owner of outlet malls in the country after Chelsea Premium Outlets, owned by Simon Property Group Inc., the nation's largest mall owner. The acquisition made Lichtenstein the owner of a number of famous buildings and properties in Chicago, where Prime Retail had previously been based. They included the IBM Plaza, 208 South LaSalle Street and the United Building. With the purchase of Prime, Lightstone also took control of some famous Chicago commercial spaces, including such world-renowned buildings as the Mies van der Rohe-designed IBM Plaza, 208 South LaSalle Street and the United Building.