In clearing the way for Google's acquisition of online ad giant DoubleClick today, the European Commission cited competition from Microsoft and others as one reason for approving the deal.

An excerpt from the EU's news release:

The Commission found that the merged entity would not have the ability to engage in strategies aimed at marginalising Google's competitors, mainly because of the presence of credible ad serving alternatives to which customers (publishers/advertisers/ad networks) can switch, in particular vertically integrated companies such as Microsoft, Yahoo! and AOL. The market investigation also found that the merged entity would not have the incentive to close off access for competitors in the ad serving market, mainly because such strategies would be unlikely to be profitable.

Microsoft had publicly opposed the deal. Brad Smith, general counsel, told a U.S. Senate subcommittee last year that the combined Google-DoubleClick would "become the overwhelmingly dominant pipeline for all forms of online advertising." He said the result would be "bad for publishers, it will be bad for advertisers and, most importantly, it will be bad for consumers." The Redmond company isn't offering any additional comments today.

Also see Google CEO Eric Schmidt's blog post about closing the deal.