BRUSSELS (Reuters) – The EU plans to set out criteria specifying the kind of dominant companies that will face tougher rules, Europe’s antitrust chief said on Monday, in a move that will likely affect Apple, Amazon, Facebook and Google.

Competition Commissioner Margrethe Vestager, who is drafting rules known as the Digital Services Act which will spell out how data should be shared and how digital marketplaces should operate, said she was looking into a list of criteria to define market influence or weight.

“Well obviously it will not be targeted at any specific company or any specific nationality. What is important is that they target a certain market weight, market influence and this is what will be guiding these criteria that we will set out,” she told Reuters in an interview.

“We are not done yet with this list of criteria but obviously we do not work backwards, from a list of companies to a list of criteria.

“We try to sort of set out a list of criteria so that businesses that have that kind of weight in the market, that kind of market influence where they do their business, that they will be within the scope of the legislation,” Vestager said.

She said working with a list of criteria rather than a list of names would be a more durable approach.

Vestager is scheduled to announce her proposal on Dec. 2 after which the Commission will negotiate with EU countries and the European Parliament to agree on legislation, a process which could take a year or two.

Apple, Facebook and Google have said any new rules should be reasonable, proportionate and based on clear parameters.