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EU: CJEU reiterates conditions for setting aside A1-declarations in Vueling Case

In the joined cases ‘Vueling Airlines’ (C-370/17 and C-37/18), the Court of Justice of the European Union has confirmed the conditions for national courts to set aside the binding force of A1-declarations in case of fraud.

Regulation no. 883/2004 ensures that only one social security system applies, even when a worker is posted to another Member State. In principle, the social security system of the Member State where the person normally carries out his activity will be applicable. In case of posting of workers, the sending Member State will deliver an A1-declaration (also called ‘E-101 form’) to the posting employer, which proves that its social security legislation is applicable for the worker, as the posted worker will only temporarily perform work in the other Member State. These A1-forms are binding for all the other EU Member States, as they should be able to trust each other regarding the fact that they have correctly granted an A1-declaration. However, in reality, it seemed relatively easy to receive an A1-declaration in certain Member States, also when the posted worker does not normally carry out his activities in this Member State, or even if he does not have any connection to this particular country (e.g. when the establishment of the posting employer turns out to be merely a mailbox).

In the case at hand, Spanish workers of the Spanish air carrier Vueling airlines, received A1 -declarations from Spain and were posted to France. However, the French Social Inspection was of the opinion that the A1-declarations were granted based on incorrect information, and the Spanish workers should be subjected to the French social security system.

In the Altun Case (C-359/19) of 2018, the CJEU already stated that national courts of the hosting Member States can set A1-declarations aside, on the condition that a request for reconsideration or withdrawal of the A-declaration has been sent to the issuing institution of the sending Member State, and that this institution has failed to take the data and facts into account with a view to a possible reconsideration or withdrawal of the forms.

However, in the Vueling Case, the French Social Inspection only filed a request with the Spanish Social Security Administration following the decision of the French Court of Appeal (after which the French ‘Cour de Cassation’ also determined to take this procedure into consideration).

The true question in this case, was whether such a request to the sending Member State was an absolute condition for the National Court to disregard the binding effect of the A1-declarations. Advocate-General Saugmansgaard was of the opinion that this is not the case. However, the CJEU decided differently and reiterated the conditions it posed in the Altun Case:

  • A prior request was addressed to the authorities that issued the A1- declaration to review it;
  • This request was not followed up satisfactorily (i.e. no further investigation was carried out nor a decision taken within a reasonable period of time); and
  • The evidence at hand shows that fraud was committed, taking into account the guarantees attached to the right to a fair trial (the employer/employee should be given the possibility to rebut the data on which the proceedings by the authority of the hosting Member State are based.

To read the full text of the case, click here.


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