The European Commission has opened an antitrust investigation into Google’s alleged violation of competition law through its ad tech policies. Regulators, who have spent the past two years informally consulting on the probe, will now assess whether Google is favoring its own services by restricting rivals’ access to user data for ad purposes. 

As part of the wide-reaching investigation, the Commission will look at Google’s display and video advertising on YouTube, Google’s ad management platform and inventory marketplace Ad Manager and AdX, along with the user data restrictions it places on third-parties including online ad rivals, publishers and general advertisers. Regulators will also examine Google’s decision to end individual user tracking on Chrome and Android as part of its Privacy Sandbox changes.

“Online advertising services are at the heart of how Google and publishers monetize their online services,” said Margrethe Vestager, the EU’s antitrust chief. “We are concerned that Google has made it harder for rival online advertising services to compete in the so-called ad tech stack.”

As the Commission notes, there is no legal deadline for concluding an antitrust case. That ultimately means that an investigation that has been informally gestating for two years could take just as long to reach its climax. If Google is found to have violated antitrust rules, it will be levied with fines and remedies. Though, not for the first time.

The EU has already fined Google for abusive ad practices on three occasions between 2015 and 2018. The web giant’s Privacy Sandbox is also under investigation in the UK.

Google said it would cooperate with the EC to illustrate the advantages of its ad products for businesses and the public. “Thousands of European businesses use our advertising products to reach new customers and fund their websites every single day,” a Google spokesperson said in a statement. “They choose them because they’re competitive and effective. We will continue to engage constructively with the European Commission to answer their questions and demonstrate the benefits of our products to European businesses and consumers.”