The European Commission has opened an in-depth second phase investigation into the proposed acquisition by Google of the online advertising technology company, DoubleClick. During the first phase of the proceedings the Commission found that the deal, which is contested by rivals such as Microsoft and Yahoo, might restrict competition in the markets for intermediation and “ad serving” in online advertising. During this second phase, the Commission will investigate whether, in the absence of this transaction, DoubleClick could become an effective competitor in the market and whether vertical concerns might arise.