A German appeals court has ordered the social media platform X to provide vetted researchers with access to publicly available data linked to Hungary's April 12 election, setting a precedent for enforcing EU digital transparency rules ahead of a contentious vote.

"We are open-sourcing our algorithm. Not sure what more they want," Elon Musk wrote in reaction on X. Musk's startup xAI owns X.

The Berlin Court of Appeal's ruling is not related to the type of algorithm used, but it orders X to share information, including the reach and engagement of posts related to Hungary's parliamentary election, Democracy Reporting International, one of the two plaintiffs, said late on Tuesday.

A court spokesperson said on Wednesday that the ruling takes immediate effect.

The decision is seen as a milestone in implementing the EU's Digital Services Act, a regulation that requires major online platforms to provide researchers with access to data to monitor risks, including disinformation, hate speech, and election manipulation.

X did not respond to Reuters' requests for comment.

PRECEDENT FOR RESEARCHER ACCESS ESTABLISHED

The plaintiffs - DRI and the Society for Civil Rights (GFF) - previously failed to obtain similar data from X for Germany's 2025 federal election.

In the current case, a lower court ruled that jurisdiction lay in Ireland, where X has its EU headquarters.

However, the Berlin appeals court revisited the issue, determining that German courts could act when there was a local problem, such as when German-based researchers were denied crucial data for public-interest work.

Ruling in favour of the two NGOs, the court said X's noncompliance affected their ability to conduct research in Germany.

"No appeal can be lodged against the decision," said Joschka Selinger, a lawyer for GFF, adding that it could be enforced through penalty payments if X fails to comply.

HUNGARY ELECTION PUSHES TRANSPARENCY DEBATE

Hungary's Prime Minister Viktor Orban is facing the biggest challenge to his rule since his Fidesz party took power in 2010 as the centre-right opposition Tisza party leads in most opinion polls. Pro-government pollsters, however, put Fidesz in the lead, while many voters remain undecided.

Previous elections in Hungary have been overshadowed by reports of media bias and disinformation.

The Hungarian government did not immediately respond to a Reuters request for comment on Wednesday.

DRI contended that the court order would lower barriers for civil society groups across Europe seeking to enforce digital rights through national courts.

Observers view the decision as a signal to major platforms operating under the DSA that failure to facilitate researcher access could lead to legal consequences in EU member states.