Elon Musk’s social media site X has been accused by the European Union of breaching its online content rules, with its “verified” blue tick accounts having the potential to “deceive” users.

The bloc’s tech regulator said users could be duped into thinking the identity of those with blue tick marks was verified, when in fact anybody can pay for a blue tick. It said it had found evidence of “malicious actors” abusing the system.

The investigation began under the EU’s Digital Services Act (DSA) – it could lead to X being fined up to 6% of its global annual turnover and being forced to change how it operates in the bloc.

Mr Musk has reacted angrily: “The DSA is misinformation,” he wrote on X.

Mr Musk – who bought the platform for $44bn in 2022 – said the DSA rules amounted to “censored speech” which he said he found unacceptable.

The tech regulator also found a lack of transparency around advertising and said X did not provide data for research use as required under EU rules.

The findings follow a seven month investigation under the DSA which requires big tech firms, like X, to take action to stop illegal content and safeguard the public.

The DSA was introduced in 2022. ByteDance’s TikTok, AliExpress and Meta Platforms are also being investigated under the act.

The Commission said that the way X designed and operated its interface for blue tick verified accounts “does not correspond to industry practice and deceives users”.

“Since anyone can subscribe to obtain such a ‘verified’ status, it negatively affects users’ ability to make free and informed decisions about the authenticity of the accounts and the content they interact with,” it added.

“There is evidence of motivated malicious actors abusing the ‘verified account’ to deceive users.”

Thierry Breton, Commissioner for Internal Market, said: “Back in the day, BlueChecks used to mean trustworthy sources of information.

“Now with X, our preliminary view is that they deceive users and infringe the DSA,” he added.

“X has now the right of defence — but if our view is confirmed we will impose fines and require significant changes.”

X was also charged with blocking researchers from accessing its public data.

“In particular, X prohibits eligible researchers from independently accessing its public data, such as by scraping, as stated in its terms of service”, the Commission said.

If found to be in breach, X would also be subject to an “enhanced supervision period to ensure compliance”.

The Commission will also continue investigations into X’s practices around dissemination of illegal content, and how well it combats the spread of fake news.