LONDON (AP) — Ireland's High Court has asked the European Court of Justice to decide whether Facebook's Dublin-based subsidiary can legally transfer users' personal data to its U.S. parent, saying there are "well-founded concerns" the practice violates European law.

In a case brought after former U.S. defense contractor Edward Snowden revealed the extent of electronic surveillance by American security agencies, the court found that Facebook's transfers may compromise the data of European citizens.

The case has far-reaching implications for social media companies and others who move large amounts of data via the internet.

Ireland's Data Commissioner had previously issued a preliminary decision that such transfers are illegal because agreements between Facebook and its Irish subsidiary don't adequately protect the privacy of European citizens.