On July 24, 2001, Silverstein Properties, owned by the famous American real estate developer Larry Silverstein, officially signed a 99-year lease agreement for the World Trade Center with the Port Authority of New York and New Jersey, acquiring the operating rights of the World Trade Center Twin Towers and the affiliated building complex for $3.2 billion. This was the largest privatization transaction since the landmark's completion. However, only seven weeks after the signing, the World Trade Center suffered devastating impacts and collapsed in the 911 terrorist attacks.