Google has lost its appeal against a €2.4 billion ($2.8bn) fine issued by EU regulators for rigging search results to weaken its competitors.
A European court upheld the fine on Wednesday after the platform was found to have steered users towards its Google Shopping service at the expense of other comparison sites.
The verdict from the EU’s General Court in Luxembourg is a victory for the bloc’s competition chief Margrethe Vestager, who has waged a series of battles against US tech companies over tax bills and business practices.
But Google won a separate case in Britain, where the Supreme Court blocked a $4bn class-action lawsuit that accused it of illegally tracking iPhone users.
It can make another appeal in the EU case by taking the case to the bloc’s highest court, the European Court of Justice.
The case resulted from complaints by price comparison websites after they reported their traffic plummeted compared with Google Shopping.
Google was fined in 2017 and told to change its search display to give more prominence to rival aggregators.
But many rivals are dissatisfied with the company's response, believing it does not guarantee fair competition in search results.
The European Consumer Organisation said Google's "misleading and unfair practices harmed millions of European consumers by ensuring that rival comparison shopping services were virtually invisible".
"In light of the ruling, we ask the European Commission to ensure that Google does not abuse its dominance as a search engine by giving its own services preference in other areas," said Monique Goyens, the organisation's director general.
The case is one of three against Google currently moving through the EU's appeals system.
At the time, the fine was the biggest issued by the EU. It was eclipsed in 2018 by a €4.3bn fine given to Google over its Android smartphone system.
In its appeal in the search engine case, Google and its parent company Alphabet argued the EU was "wrong on the law, the facts and the economics".
But the court said it dismissed "for the most part the action brought by the two companies, and upholds the fine imposed by the Commission".
It said that by favouring its own shopping service over rivals in its search results, "Google departed from competition on the merits".
"Today's judgment delivers the clear message that Google's conduct was unlawful and it provides the necessary legal clarity for the market," the European Commission said.
A Google representative said the company would examine the ruling but had made changes to comply with the EU’s objections.
“Our approach has worked successfully for more than three years, generating billions of clicks for more than 700 comparison shopping services,” the representative said.
Amazon, Apple and Facebook are the targets of separate EU investigations over possible breaches of competition rules.
Brussels has plans to issue mammoth fines of up to 10 per cent of sales on tech companies that break the rules.