The Commission has opened a formal probe into Luxembourg’s tax treatment of fast food giant McDonald’s having taken a preliminary view that Luxembourg granted a tax ruling which breached EU State aid rules.

According its press release, the Commission will assess whether Luxembourg authorities selectively derogated from the provisions of their national tax law and the Luxembourg-US Double Taxation Treaty and thereby gave McDonald’s an advantage not available to other companies in a comparable factual and legal situation.

Since June 2013, the Commission has been investigating the tax ruling practices of Member States. It extended this information inquiry to all Member States in December 2014. The Commission in October 2015 decided that tax rulings for Fiat in Luxembourg and Starbucks in the Netherlands granted illegal selective tax advantages to the companies in breach of EU state aid rules. The Commission also has ongoing state aid investigations into tax rulings concerning Apple in Ireland, Amazon in Luxembourg and Belgium’s “excess profit” ruling system.