BRUSSELS, July 12 (Reuters) - Elon Musk's social media

company X breached EU online content rules, EU tech regulators

ruled on Friday in a finding that could lead to a fine and

significant changes in how it operates.

The move by the European Commission follows a seven-month

long investigation under the Digital Services Act (DSA) which

requires very large online platforms and search engines to do

more to tackle illegal content and risks to public security.

ByteDance's TikTok, AliExpress and Meta Platforms ( META )

are also being investigated under the DSA.

The EU executive singled out X's dark patterns, advertising

transparency and data access for researchers.

It said X's verified accounts which carry a blue checkmark

do not correspond to industry practice and negatively affect

users' ability to make free and informed decisions about the

authenticity of the accounts they interact with.

X has also failed to comply with a DSA requirement that

companies provide a searchable and reliable advertisement

repository, the Commission said.

X was also charged with blocking researchers from accessing

its public data. The company, which will have several months to

respond to the charges, could face a fine as much as 6% of its

global turnover if found guilty of breaching the DSA.

"X has now the right of defence - but if our view is

confirmed we will impose fines and require significant changes,"

EU industry chief Thierry Breton said in a statement.

The Commission said separate investigations continue into

dissemination of illegal content on X and measures it has taken

to counter disinformation.