The European Union (EU) is flexing its muscles against tech giants, and this time, Elon Musk‘s social media platform X (formerly Twitter) is in the crosshairs. The EU’s executive arm, the European Commission, launched an investigation last year to see if X is complying with the Digital Services Act (DSA), a new law requiring Big Tech companies to take stricter responsibility for the content on their platforms.

On Friday, the commission revealed its preliminary findings, and they’re not good news for X. The commission alleges that X is breaking the DSA in three key areas: dark patterns, advertising transparency, and data access for researchers.

The first issue concerns “dark patterns.” These are deceptive design elements that nudge users towards certain actions, often without their full awareness. The commission specifically pointed to X’s use of blue checkmarks for verified accounts. Unlike industry standards, on X, anyone can apparently subscribe to a service and get verified. This lack of clear verification criteria creates confusion and opens the door for “motivated malicious actors” to exploit the system and mislead users.

The second point of contention is advertising transparency. The commission accuses X of employing design features and obstacles that make it difficult to understand who is behind the ads users see. This lack of transparency makes it harder for users to make informed decisions about the information they’re consuming.

Finally, the commission alleges that X is failing to comply with the DSA’s requirement to provide public data access to researchers. This data is crucial for independent researchers to study online trends and potential societal harms associated with social media platforms.

Margrethe Vestager, the EU’s antitrust chief, made the commission’s position clear in a statement: “In our view, X does not comply with the DSA in key transparency areas, by using dark patterns and thus misleading users, by failing to provide an adequate ad repository, and by blocking access to data for researchers. The DSA has transparency at its very core, and we are determined to ensure that all platforms, including X, comply with EU legislation.”

In a post on X, Elon Musk took a combative stance. He claimed the commission offered his company an “illegal secret deal” – a deal that would have waived potential fines in exchange for X quietly censoring content. Musk went on to allege that “other platforms accepted that deal,” though he provided no evidence to support this claim.

If the commission’s findings are confirmed, X could face a hefty fine of up to 6% of its global annual revenue. The EU is serious about enforcing the DSA, and X is not the only platform under scrutiny. The commission is also investigating similar concerns with TikTok, Alibaba’s AliExpress, and Meta (formerly Facebook).