The action by the European Commission comes two months after it ordered Luxembourg to recover up to 30 million euros ($31.7 million) from Fiat Chrysler Automobiles (FCAU) and the Dutch to do the same for Starbucks (SBUX) because their tax deals were seen as unlawful aid.

The E.U. competition enforcer said McDonald’s has not paid any corporate taxes in Luxembourg or the United States on royalties paid by franchisees in Europe and Russia since 2009 as a result of two tax rulings by the Luxembourg authorities.

“The purpose of double taxation treaties between countries is to avoid double taxation – not to justify double non-taxation.”

The Commission said McDonald’s Europe Franchising was exempted from paying taxes on this income in Luxembourg on the grounds that the profits were subject to taxation in the United States. However, when the ruling was granted in 2009, these profits were not subjected to tax in the United States.

In a second ruling, Luxembourg agreed that McDonald’s did not have to prove that this income was subject to U.S. tax, the Commission said.

The case presents yet another headache for Commission President Jean-Claude Juncker as Luxembourg developed its favorable tax system during the near quarter-century that he served as the Grand Duchy’s finance minister or prime minister.

Vestager’s move against McDonald’s came following media reports on tax dodging and evidence from trade unions.

“For too long, McDonald’s has stashed billions in tax havens and ducked contributing to state coffers while simultaneously imposing poverty wages on its workers… and it’s time that the company be held accountable” Scott Courtney, organizing director at SEIU, said in a statement.

SEIU represents 2 million healthcare, public sector and property service workers in the United States, Canada and Puerto Rico.