The Merchants' Exchange Building is a building in the city of Philadelphia which is in the state of Pennsylvania in the United States. It is in a historical neighborhood called Old City. Architect William Strickland designed the building. It was built starting in the year 1832 and was done in 1834. The Merchants' Exchange Building was the first office building in the city. It used to be a brokerage house. In 1875, the Philadelphia Stock Exchange moved into the building. 