Türkiye's competition board said on Tuesday it launched an investigation into Meta Platforms over a possible violation of competition law by linking its social media platforms Threads and Instagram.

In a statement, the Competition Authority (RK) said the preliminary research produced serious and sufficient evidence to open an investigation to decide whether linking the Threads app to the Instagram app violated competition law.

Meta was hit with a $18.63 million fine in October last year for breaking competition law. The RK said the company held a dominant position in personal social networking services and online video advertising and had obstructed competitors by merging data collected through its core services Facebook, Instagram and WhatsApp.

Launched in July this year, Threads has been portrayed as a challenger to X, formerly known as Twitter, which remains one of the world's biggest social media platforms despite its struggles following tech tycoon Elon Musk's takeover in 2022.

Threads accounts are synched to Instagram at the outset, allowing users to keep their usernames and retain followers.

Threads has almost 100 million users who are active at least once a month, said Facebook founder and Meta chief executive Mark Zuckerberg in October. After its launch, Threads broke the 100 million sign-up mark within a few days – but user activity fell soon after.

Zuckerberg remained convinced that Threads could become a service with 1 billion users in a few years.

Instagram has more than two billion users that it hopes will turn to its Threads spin-off.

X, meanwhile, says it has more than 200 million daily users.