1. Context

When sending employees to work abroad, an employer must apply for certain certificates, such as an A1 secondment certificate.

This certificate is a declaration regarding the social security scheme applicable to the employee when working in more than one EU Member State. The certificate confirms the applicable social security scheme for the period indicated in the declaration and states in which country the employee must pay social security contributions.

The A1 secondment certificate is in principle binding for the authorities of the other Member States, as long as the certificate has not been withdrawn or declared invalid by the issuing Member State.

2. Case history

The case which led to the ruling of the Supreme Court of 19 June 2018 concerned criminal proceedings against a Belgian construction company. During the criminal investigation, it was determined that the company contracted with Bulgarian subcontractors whose sole activity appeared to be posting employees from Bulgaria. The concerned employees possessed an A1 secondment certificate issued in Bulgaria, but all the evidence indicated that the Bulgarian subcontractors were merely a cover to circumvent the Belgian social security legislation.

The appeal to the Supreme Court was directed against the ruling of the Antwerp Court of Appeal of 10 September 2015, in which the Court did not consider itself bound by the A1 secondment certificates, as they had, according to the Court, been obtained fraudulently.

By the ruling of 7 June 2016, the Supreme Court decided to question the European Court of Justice regarding the possibility for Belgian courts, notwithstanding the existence of an A1 secondment certificate, to subject workers to the Belgian social security scheme in case of fraud or abuse.

In its ruling of 6 February 2018, the European Court of Justice decided that if an A1 secondment certificate is obtained fraudulently, the issuing authority must re-examine the approval process in light of the submitted information and, where appropriate, withdraw it. However, this must be done within a reasonable period and the undertakings that have been working with posted employees covered by such certificates must be able to exercise their rights of defence.

3. Ruling of the Supreme Court of 19 June 2018

The Supreme Court confirms the ruling of the Antwerp Court of Appeal as it decided not to take into account the A1 secondment certificate in accordance with the criteria set out by the Court of Justice.

Therefore, it is clear that European law cannot be used abusively to circumvent the normally applicable social security scheme. The judge in the receiving Member State can therefore (under certain conditions) refuse to take into account an A1 secondment certificate if it has been obtained fraudulently.