About One William Street
1 William Street is an office building located in New York City. The building, completed in 1907, was built for J & W Seligman, an investment bank. In 1928, the building was acquired by Lehman Brothers, another investment bank, which remained headquartered there until 1980. The building is presently owned by Intesa Sanpaolo, Italy's largest bank. In 1996, the building was designated as a landmark by the New York City Landmarks Preservation Commission.