Chicago 's Sears Tower renamed Willis Tower after London insurance company . Residents join online group opposing Landmark 's name change . , England-based insurance broker Willis Group Holdings . Landmark opened in 1973 with original tenants Sears Roebuck & Co .
Chicago 's Sears Tower renamed Willis Tower after London insurance company . Residents join online group opposing Landmark 's name change . Landmark opened in 1973 with original tenants Sears Roebuck & Co .