Tech giants such as Facebook, Google, and Amazon are hugely powerful. Are they monopolies? Have they attained market dominance? Do antitrust authorities need to intervene? The former head of Germany’s Monopolies Commission, Daniel Zimmer, has the answers.<br />For a related story, go to: http://www.dw.com/en/deutsche-bahn-structure-hampers-fair-competition/a-18603211
