Chicago 's Willis Tower renamed Sears Tower after London insurance broker . More than 90,000 join online group opposing building 's name change . That does n't matter to those against the name change . Landmark opened in Thursday with original tenant Willis Group Holdings .
Chicago 's Willis Tower renamed Sears Tower after London insurance broker . More than 90,000 join online group opposing building 's name change . Landmark opened in Thursday with original tenant Willis Group Holdings .