By Foo Yun Chee

BRUSSELS (Reuters) - A record EU antitrust fine of 4.3-billion-euro ($4.5 billion) imposed on Google seven years ago punished the tech giant over its innovation, the Alphabet unit told Europe's top court on Tuesday, as it asked judges to scrap the EU decision.

Google's appeal to the Luxembourg-based Court of Justice of the European Union comes two years after a lower tribunal sided with the European Commission which said the company used its Android mobile operating system to quash rivals. 

The lower court trimmed the fine to 4.1 billion euros.

"Google does not contest or shy away from its responsibility under the law, but the Commission also has a responsibility when it runs investigations, when it seeks to reshape markets and second-guess pro-competitive business models, and when it imposes multi-billion-euro fines," Google lawyer Alfonso Lamadrid told the court.

"In this case, the Commission failed to discharge its burden and its responsibility and, relying on multiple errors of law, punished Google for its superior merits, attractiveness and innovation," he said.

Lamadrid defended Google's 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 Android systems.

EU antitrust enforcers had said such requirements thwarted competition.

Lamadrid argued that "these agreements and conditions did not restrict competition, they fostered it." 

Judges will rule in the coming months. Their decision would be final and cannot be appealed. Google is currently in the EU crosshairs over its lucrative ad tech business, over which a decision is likely this year.

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

($1 = 0.9533 euros)

(Reporting by Foo Yun Chee; Editing by Bernadette Baum; Editing by Bernadette Baum)