Brandywine Realty Trust is a real estate investment trust that acquires, develops, and leases office, industrial, retail, and mixed-use properties throughout the U.S. The vast majority of the company's real estate portfolio is composed of urban and transit-oriented suburban office buildings. In terms of total square footage, these assets are primarily located in the major real estate markets of the Mid-Atlantic US, including suburban Pennsylvania, Philadelphia's Central Business District, and Metropolitan Washington D.C. Brandywine derives nearly all of its revenue in the form of rental income from tenants. The company's largest revenue-generating customers are U.S. Government, technology, defense, and financial services entities in its three primary markets.