How have Apple and Ireland reacted?
Apple and the Irish government have both vowed to appeal the decision.
In a statement, Apple said: "The European Commission has launched an effort to rewrite Apple’s history in Europe, ignore Ireland’s tax laws and upend the international tax system in the process. The commission’s case is not about how much Apple pays in taxes, it’s about which government collects the money. It will have a profound and harmful effect on investment and job creation in Europe. Apple follows the law and pays all of the taxes we owe wherever we operate. We will appeal and we are confident the decision will be overturned.”