EU probes Google's digital ad business
Google is in the EU antitrust spotlight again as regulators open an investigation into its lucrative digital advertising business to examine whether the US tech giant favours its own business over rivals, advertisers and online publishers.
The Alphabet Inc company generated $US147 billion ($A196 billion) in revenue from online ads last year, more than any other company in the world.
Ads on its properties, including search, YouTube and Gmail, accounted for the bulk of sales and profits.
About 16 per cent of revenue came from its display or network business, in which other media companies use Google technology to sell ads on their website and apps.
The European Commission said it would investigate whether Google distorts competition by restricting access to third parties to user data for advertising purposes on websites and apps, while reserving such data for its own use.
"We are concerned that Google has made it harder for rival online advertising services to compete in the so-called ad tech stack," European Competition Commissioner Margrethe Vestager said on Tuesday.
"We will also be looking at Google's policies on user tracking to make sure they are in line with fair competition."
Google said it would engage constructively with the commission.
"Thousands of European businesses use our advertising products to reach new customers and fund their websites every single day. They choose them because they're competitive and effective," a spokesperson said.
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