BRUSSELS, July 2 (Reuters) - Alphabet's Google on Thursday lost its long-running fight against a record EU antitrust fine for using its Android mobile operating system to block rivals, a court ruling which is seen as likely to boost Europe's crackdown on Big Tech.

The European Commission, the bloc's antitrust regulator, has fined Google billions of euros over several antitrust violations in the last 15 years, but the cases dragged through the courts as the search giant filed appeals.

The Android fine was imposed in 2018, a year after the Commission fined Google €2.42 billion ($2.77 billion) for using its shopping comparison service to gain ​an unfair advantage over smaller rivals. Google lost an appeal against that in 2021.

The appeal for this case lasted longer.

The Commission fined Google €4.34 billion for agreements which forced phone manufacturers to pre-install Google Search, the Chrome browser, and the Google Play app store on their Android devices and prevented them from using rival systems.

A lower tribunal subsequently trimmed the fine to €4.1 billion in 2022. Google then appealed to the Luxembourg-based Court of Justice of the European Union, Europe's highest.

The court sided with the EU antitrust enforcer.

"The appeal brought by Google and its parent company Alphabet against the judgment of the General Court is dismissed, thereby confirming the penalty imposed for Google Search's abuse of a dominant position in the context of the Android operating system," judges said.

A Google spokesperson said that the judgment failed to take into account its investment to ensure Android remains open, interoperable and free.

"In any event, we adapted our agreements to comply with the initial decision back in 2018, and we remain focused on continued innovation and openness for our users, partners and developers", Google said.

Google has racked up close to €11 billion in EU fines in the last decade for various antitrust infringements.

While the record antitrust fine is less than 3% of Alphabet's annual profit, the loss could embolden other regulators and companies to chase Google for damages.

The loss of the shopping comparison case had led to a slew of lawsuits against Google by companies claiming damages worth billions of dollars across half a dozen countries.

A Swedish court ordered Google to pay about $1.5 billion in damages to PriceRunner, the price comparison business now owned by Klarna, on Wednesday.

For Google, more fines look likely in the near future for allegedly favouring its own services and products in search results and for practices related to its app store, both of which fall under the Digital Markets Act aimed at reining in the power of Big Tech.

The case is C-738/22 P Google and Alphabet v Commission.

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