The European Commission's ruling has serious consequences for those with money invested in Arco. The European Commission says that those with money invested in Arco are share-holders rather than savers.
The fact that Europe has now said that the Belgian's state's guarantees for money invested in Arco are illegal means that, in principle, investors in Arco have lost their money.
The outgoing Finance Minister Koen Geens plans to take the case to the European Court. However, he intends to study the commission's ruling in detail before doing so.
Mr Geens adds that a legally-sound solution for Arco investors should be high on the agenda once talks to form a new federal coalition get started.
"Because if you have been promising people since 2008 that they won't suffer if Arco goes under, it is difficult to explain that a reimbursement won't be forthcoming.