The move follows a case brought by Austrian law student and privacy activist Schrems about Facebook’s handling of his data in the US.
He made his complaint in Dublin, home to Facebook’s European HQ, where it was taken up the Irish Data Protection Commissioner Helen Dixon.
Irish High Court Judge Caroline Costello ruled on Tuesday that the Commissioner had raised, "well-founded concerns that there is an absence of an effective remedy in US law compatible with the requirements of Article 47 of the Charter (of Fundamental Rights).
As a result, she said she had decided to ask the European Union Court of Justice (CJEU) for a preliminary ruling in the case: "European Union law guarantees a high level of protection to EU citizens…they are entitled to an equivalent high level of protection when their data is transferred outside of the European Economic Area," Costello said.
While the Schrems case specifically cites Facebook's use of so-called standard contractual clauses (SCCs), the case covers the validity of all European Commission agreements on how data is transferred between the US and EU, which also includes Privacy Shield agreement.