Simon Property Group is the nation's largest shopping mall and retail center owner, with a portfolio of over 200 retail properties totaling approximately 185 million sq. ft. of leasable space across more than 35 states and Puerto Rico. The self-managed, self-administered real estate investment trust (REIT) owns, develops, and manages regional shopping malls, outlet malls (under the Premium Outlet and The Mills brands), boutique malls, and shopping centers. Its portfolio is concentrated in the US's Southeast, Midwest, and Northeast. The REIT also has stakes in outlet centers in Canada, Mexico, Europe and Asia. CEO and chairman David E. Simon is the son of Melvin Simon, who founded the firm with his brother, Herbert.