Google’s $3.1 billion (£1.5 billion) acquisition of DoubleClick, the largest broker of online banner advertising, is likely to be delayed for months by the European Commission, advisors close to the internet search giant believe.

The European competition watchdog will decide by October 26 whether to launch a full investigation into the takeover, which would hold up the deal for at least four months. The Commission could block it altogether if the investigation reveals significant competition issues.

A full-blown inquiry would be construed as an interim victory for Microsoft, which is lobbying fiercely against the DoubleClick deal on competition and privacy grounds.

Microsoft, which is fighting to reinvent itself as a force in online advertising, was beaten in an auction for DoubleClick this year. It is thought that Microsoft matched Google’s bid but was snubbed by Helman & Friedman, DoubleClick’s private equity owner.

Last week, Microsoft was stung by a bruising defeat at the hands of Europe’s competition watchdog, when a €497 million (£346.2 million) fine for anticompetitive behaviour was upheld. Analysts suggest that Europe’s regulators have been emboldened by that decision, an attitude that could cost Google time and legal fees.

Advisors close to Google, which already dominates the market for search-based advertisements, believe that the DoubleClick case will rest on whether online advertising is judged to be a distinct market or part of a broader landscape that includes print, television and radio. “Determining whether that is the case is going to be a hugely fact and data-intensive exercise,” one lawyer said. “It is very hard to see it happening in a month.” Google argues that the deal is “positive for users and advertisers and fosters competition”. Moreover, its belief that online adverts should not be treated as a separate market was boosted by a German ruling to that effect relating to Microsoft’s acquisition of aQuantive, another online advertising group, for $6 billion.

Yet its DoubleClick deal also faces opposition in the United States. On Thursday, Microsoft will send Brad Smith, its general counsel, to give evidence at a Senate hearing on the acquisition, which will also examine privacy fears. Commentary, page 41

It all ads up

40% Proportion of UK online advertising spending taken by Google

80% Estimated proportion of adverts that would be accounted for by combined Google and DoubleClick

$2bn Estimated profit made by Hellman & Friedman, DoubleClick’s owner

$3.9bn Google’s most recent quarterly revenue

Source: Times database

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