The European Commission (EC) has blocked the proposed GBP 10.25 billion (USD 13.8 billion) acquisition of Telefonica’s UK cellular operator O2 by the Hong Kong-based group CK Hutchison, which operates under the ‘3’ brand. This follows a failed tie-up between two cellcos in Denmark in 2015. Yet it was a markedly different situation several years ago, when the EC gave the green light to a raft of mobile mergers. So why is the EC now seemingly less receptive to such deals when it has agreed to them in the past?