BRUSSELS, Oct 4 (Reuters) - Meta Platforms ( META ) must

restrict the use of personal data harvested from Facebook for

targeted advertising, Europe's top court ruled on Friday,

backing privacy activist Max Schrems.

Schrems took his grievance to an Austrian court, saying he

had been targeted by advertisements as a result of Meta's

personalised advertising based on processing personal data.

The Austrian tribunal then sought guidance from the

Luxembourg-based Court of Justice of the European Union (CJEU),

which on Friday backed Schrems.

"An online social network such as Facebook cannot use all of

the personal data obtained for the purposes of targeted

advertising, without restriction as to time and without

distinction as to type of data," the CJEU said.

The judges said the principle of data minimisation under EU

privacy rules known as the General Data Protection Regulation

(GDPR) sets this out.

Meta responded by saying it has invested more than 5 billion

euros to embed privacy in its products and that it does not use

special categories of data that users provide to personalise ads

while advertisers are not allowed to share sensitive data.

"Everyone using Facebook has access to a wide range of

settings and tools that allow people to manage how we use their

information," a Meta spokesperson said.

Schrems' lawyer Katharina Raabe-Stuppnig welcomed the

ruling.

"Following this ruling only a small part of Meta's data pool

will be allowed to be used for advertising - even when users

consent to ads. This ruling also applies to any other online

advertisement company, that does not have stringent data

deletion practices," she said.

Schrems has taken Meta to court a number of times for

alleged GDPR breaches.

The case is C-446/21 Schrems (Communication of data to the

general public).