Alphabet, the company that owns Apple, Meta, and Google, is being investigated for possible violations of the 2022-introduced Digital Markets Act (DMA).
The companies may be hit with hefty fines equal to 10% of their yearly revenue if it is determined that they violated the regulations.
On Monday, EU antitrust chief Margrethe Vestager and industry president Thierry Breton announced the investigations.
Three weeks have passed since the EU fined Apple €1.8 billion (£1.5 billion) for breaking music streaming competition laws.
In the meantime, the US claimed Apple was monopolizing the smartphone market in a landmark lawsuit against the tech giant that was filed last week.
According to the EU’s inquiry, which was made public today, Apple and Alphabet are restricting anti-steering, or making it more difficult for apps to inform consumers about alternatives to using the app stores’ in-app purchases for cheaper prices.