Austrian advocacy group NOYB on Monday filed a complaint against social media platform X accusing the Elon Musk-owned company of training its artificial intelligence (AI) with users' personal data without their consent in violation of EU privacy law.

The group led by privacy activist Max Schrems announced that it had filed General Data Protection Regulation (GDPR) complaints with authorities in nine European Union authorities to ramp up pressure on the Irish data protection authority DPC.

Ireland's Data Protection Commission, the lead EU regulator for most of the top U.S. internet firms due to the location of their EU operations in the country, has sought an order to suspend or restrict X from processing the data of users for the purposes of developing, training or refining its AI systems.

X has agreed not to train its AI systems for now using personal data collected from EU users before they had the option to withdraw their consent, an Irish court heard last week.

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However, NOYB said the DPC complaint is mainly concerned with mitigation measures and a lack of cooperation by X, and does not question the legality of the data processing itself.

"We want to ensure that Twitter fully complies with EU law, which – at a bare minimum – requires to ask users for consent in this case," said Schrems in a statement, referring to X by its previous name.

At the hearing last week, an Irish court found that X had only given its users the opportunity to object several weeks after the start of data collection.

X did not immediately reply for a request for comment on Monday. The X Global Government Affairs account on Friday said the company would continue to work with the DPC about AI issues.

In June, Facebook parent company Meta announced that it would not be launching its AI assistant in Europe for the time being after the Irish DPC told it to delay its plan.

NOYB had lodged complaints in several countries against the use of personal data for training the software in this case too.