Press Release, here.
"Although WhatsApp is not active in online advertising, the Commission examined whether the transaction could strengthen Facebook's position in that market and hamper competition. In particular, the Commission examined the possibility that Facebook could (i) introduce advertising on WhatsApp, and/or (ii) use WhatsApp as a potential source of user data for improving the targeting of Facebook's advertisements. The Commission concluded that, regardless of whether Facebook would introduce advertising on WhatsApp and/or start collecting WhatsApp user data, the transaction would not raise competition concerns. This is because after the merger, there will continue to be a sufficient number of alternative providers to Facebook for the supply of targeted advertising, and a large amount of internet user data that are valuable for advertising purposes are not within Facebook's exclusive control."