The European Union said Friday that blue checkmarks from Elon Musk’s X are deceptive and that the online platform falls short on transparency and accountability requirements, the first charges against a tech company since the bloc’s new social media regulations took effect.

The European Commission outlined the preliminary findings from its investigation into X, formerly known as Twitter, under the 27-nation bloc’s Digital Services Act.

The rulebook, also known as the DSA, is a sweeping set of regulations that requires platforms to take more responsibility for protecting their European users and cleaning up harmful or illegal content and products on their sites, under threat of hefty fines.

Regulators took aim at X’s blue checks, saying they constitute “dark patterns” that are not in line with industry best practice and can be used by malicious actors to deceive users.

Before Musk’s acquisition, the checkmarks mirrored verification badges common on social media and were largely reserved for celebrities, politicians and other influential accounts. After Musk bought the site in 2022, it started issuing them to anyone who paid $8 per month for one.

“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,” the commission said.

The accusations, which also include blocking data access to researchers and shortcomings in its ad database, drew a combative response from Musk.

“The European Commission offered X an illegal secret deal: if we quietly censored speech without telling anyone, they would not fine us,” he wrote on the site. “The other platforms accepted that deal. X did not.” He did not provide further details.

An email request for comment to X resulted in an automated response that said “Busy now, please check back later.” Its main spokesman reportedly left the company in June.

“Back in the day, BlueChecks used to mean trustworthy sources of information,” European Commissioner Thierry Breton said in a statement. “Now with X, our preliminary view is that they deceive users and infringe the DSA.”

The commission also charged X with failing to comply with ad transparency rules. Under the DSA platforms must publish a database of all digital advertisements that they’ve carried, with details such as who paid for them and the intended audience.

But X’s ad database isn’t “searchable and reliable” and has “design features and access barriers” that make it “unfit for its transparency purpose,” the commission said. The database’s design in particular hinders researchers from looking into “emerging risks” from online ads, it said.

The company also falls short when it comes to giving researchers access to public data, the commission said. The DSA imposes the provisions so that researchers can scrutinize how platforms work and how online risks evolve.

But researchers can’t independently access data by scraping it from the site, while the process to request access from the company through an interface “appears to dissuade researchers” from carrying out their projects or gives them no choice but to pay high fees, it said.

X now has a chance to respond to the accusations and make changes to comply, which would be legally binding. If the commission isn’t satisfied, it can levy penalties worth up to 6% of the company’s annual global revenue and order it to fix the problem.

The findings are only a part of the investigation. Regulators are still looking into whether X is failing to do enough to curb the spread of illegal content — such as hate speech or incitement of terrorism — and the effectiveness of measures to combat “ information manipulation,” especially through its crowd-sourced Community Notes fact-checking feature.

TikTok, e-commerce site AliExpress and Facebook and Instagram owner Meta Platforms are also facing ongoing DSA investigations.