Starbucks (Photo: John Disney / ALM)

Margrethe Vestager, the EU's antitrust czar, has suffered a partial setback in her drive to stop EU countries from granting sweetheart tax deals to multinational companies.

The EU's General Court ruled today that the commission was wrong to order Starbucks to pay €30 million ($33 million) in unpaid taxes to the Netherlands. In a separate judgment, it ruled that the commission was correct in ordering Fiat Chrysler Finance Europe to repay a similar amount to the Netherlands.

Responding to the rulings, Vestager, who has just been nominated for a second term as commissioner for competition, said in a statement: "All companies, big and small, should pay their fair share of tax. If member states give certain multinational companies tax advantages not available to their rivals, this harms fair competition in the EU.

"Today's judgments," she continued, "give important guidance on the application of EU state aid rules in the area of taxation. At the same time, each case has its specificities and involves complex legal questions."

She said the commission would study the judgments carefully before deciding on possible next steps.

The commission has the right to appeal the court's ruling in the EU's Court of Justice, the bloc's highest court.

Vestager said the commission would "continue to look at aggressive tax planning measures under EU state aid rules to assess if they result in illegal state aid".

The court was ruling on two decisions taken by the commission in 2015: one against Starbucks and its tax arrangements in the Netherlands, and one for Fiat Chrysler Finance Europe in Luxembourg.

Both commission decisions were based on the argument that the companies benefited from special arrangements, granted by the tax authorities in the countries in which they were operating, which meant they paid lower taxes than their competitors.

In the case of Starbucks, the EU court found the commission had failed to prove that the company benefited from the tax arrangement.

For Fiat Chrysler Finance Europe, the court found that a ruling by the Luxembourg tax authorities approving arrangements did benefit the company compared to its competitors.

The companies and the governments that granted the tax deals have the right to appeal the court's decisions.

Vestager's drive to clamp down on EU governments granting sweetheart deals to multinational companies was a major part of her five years as commissioner for competition. She also ordered Apple to repay $14 billion in unpaid taxes to Ireland. A judgment in that case is expected in the coming months.

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