The European Commission is investigating allegations that Google has abused its dominant position in online search to promote its other services, such as price comparators, the Commission announced Tuesday.
The investigation will also look into alleged abuse of exclusivity clauses that discourage sites carrying advertisements served by Google from also carrying advertisements served by its rivals.
PC manufacturers and software developers will also be questioned to see whether they were pressured by Google to make its search service the default in their products, the Commission said.
The Commission is also concerned that Google may be imposing restrictions on the transfer of information about online advertising campaigns from its service to competing online advertising platforms.
Complaints from other search service providers sparked the investigation, it said.
The companies told the Commission that Google treated their services unfavorably in its unpaid and sponsored search results. They also alleged that Google gave its own services preferential placement, the Commission said.
The Commission is particularly concerned that Google may have lowered the ranking in its search results of rival providers of services such as price comparators, in order to promote similar services of its own.
In February, Google revealed that it was the target of a preliminary investigation by the Commission, following complaints filed by French legal search engine ejustice.fr and by two price comparators, Foundem of the UK and Ciao of Germany.
Last week, a US researcher published details of his investigation into Google's treatment of its own supplementary search services compared to those of its rivals.
The Commission stressed that opening the investigation does not imply that it already has proof of any infringements: merely that it is looking for it. Google has been notified of the investigation, the length of which will depend to some extent on the company's cooperation, the Commission said.
Google will work with the Commission to address its concerns, and has "worked hard to do the right thing by our users and our industry ... making it easy for users to take their data with them when they switch services," a company representative said.