The Court of Justice has given a judgment in the case Salomie and Oltean.
The principles of legal certainty and of the protection of legitimate expectations do not preclude, in circumstances such as those of the dispute in the main proceedings, a national tax authority from deciding, following a tax audit, to subject transactions to value added tax and to impose the payment of surcharges, provided that that decision is based on clear and precise rules and that that authority's practice has not been such as to give rise, in the mind of a prudent and well-informed trader, to a reasonable expectation that that tax would not be levied on such transactions, this being a matter for the referring court to determine. The surcharges applied in such circumstances must comply with the principle of proportionality. Council Directive 2006/112/EC precludes, in circumstances such as those of the dispute in the main proceedings, national rules under which the right to deduct input value added tax, due or paid on goods and services used in the context of taxed transactions, is refused to the taxable person, who must nevertheless pay the tax that he ought to have paid, for the sole reason that he was not identified for value-added-tax purposes when he carried out those transactions, so long as he has not been duly identified for value added tax purposes and the tax return for the tax due has not been filed.