With more than 30 million square feet of class A office and office/flex properties located in the Northeast, Mack-Cali Reality Corporation is one of the United States largest real estate investment trusts. Serving approximately 2,200 tenants, the company had a total market capitalization of approximately $5.4 billion in December 2005. The company was formed more than 50 years ago and has been a publicly traded real estate investment trusts since 1994. Mack-Cali Reality Corporation is headquartered in Cranford, N.J.