Google suffered a legal blow at the European Court of Justice on Thursday when the body's adviser recommended that a 2.4 billion euro ($2.6 billion or Sh413 billion) fine levied on it for anti-competitive practices be upheld.
Although such opinions are not binding, they do carry weight and are often followed by EU judges in their rulings.
In this case, the opinion will feed into a legal battle Google has been waging to overturn the fine the European Commission hit it with in 2017.
The commission determined that Google abused its dominant position by favouring its own Google Shopping service in results from its ubiquitous search engine.
Google, owned by US tech titan Alphabet, was forced to change how it displays search results.
At the time the fine was a record. But it was overtaken in 2018 by a 4.3-billion-euro penalty Brussels levied on Google for putting restrictions on Android smartphones to boost its internet search business.
Google lost a first round in its challenge over the Google Shopping case when the lower EU General Court in 2021 found against it and upheld the commission's penalty.
However, that court did dismiss part of the commission's case by saying it had not proven that there were anti-competitive effects in the search engine market.
Google then mounted an appeal to the higher EU Court of Justice to try to get the lower court's decision set aside.
Confirm the fine
In her opinion, Advocate General Juliane Kokott recommended the Court of Justice's judges "dismiss the appeal and thus confirm the fine imposed on Google".
The adviser said Google's favouritism for its own service over rivals' constituted "an independent form of abuse" if it gained a competitive advantage, even a potential one.
- Google awaits ruling -
The lower court and the commission "rightly noted" that Google leveraged its dominant position to give "unequal treatment" to competitors, she said.
Google told AFP it would review the legal opinion and await the final ruling by the Luxembourg-based court, which is not expected for months.
"Irrespective of the appeal, we continue to invest in our remedy, which has been working successfully for several years, and will continue to work constructively with the European Commission," a spokesperson said.
The European Commission has hit several US Big Tech companies with fines in recent years as it seeks to regulate online services and better protect European consumers and firms.
Last year the EU brought in laws, the Digital Services Act and the Digital Markets Act, that crack down on illegal online content and impose tough new curbs on internet giants.
Google has so far borne the brunt of the European Commission's antitrust scrutiny, racking up a total of eight billion euros in fines.
It is currently the target of another probe by Brussels, launched in 2021, to see whether it abused its position to favour its online display advertising technology, including on YouTube.
Depending on the outcome, that could result in another massive fine and a requirement that Google change its practices.
Alphabet brought in $76.7 billion in revenue in the third quarter of last year, most of it from online advertising, making $19.7 billion in profit.
In 2022, the tech giant had annual revenue of $282.8 billion.