Since June 2013, the European Commission started a sweeping crusade against tax rulings, alleging that companies have received state aid in form of tax relief through tax rulings.
"The main reason behind our state aid action is the realization that governments can distort competition in the Single Market not only by granting subsidies but also by offering sweetheart tax deals. In particular, the deals we have identified benefit only a handful of large multinationals that can put enticing investments and job opportunities on the negotiating table. Smaller companies cannot wield the same bargaining power."
February 3, 2015: EU Commission starts proceeding against Belgium's excess profit ruling system
February 25, 2015: "Unhappy Meal" report - EU/US trade unions call for action from EU Commission
May 26, 2015: Amazon introduced a new tax structure in the UK, Germany, Italy and Spain. The Commission said it "will consider changes to the group tax structure, but these changes going forward don't affect any advantages the company may have received in the past."
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 in-depth state aid investigations into tax rulings concerning Apple in Ireland, Amazon in Luxembourg and Belgium's "excess profit" ruling system.
More information: https://zwitsersbankgeheim.wordpress.com/2016/01/01/taxation-and-eu-state-aid-law/