"It is imperative that EU and US governments ensure that they continue to provide reliable methods for lawful data transfers and resolve any issues relating to national security," a Facebook spokeswoman said in an emailed statement to AFP.
"This case is not about Facebook. The Advocate General (top adviser to the EU court) himself said that Facebook has done nothing wrong."
The decision followed a complaint lodged by Max Schrems, an Austrian privacy campaigner, with Irish authorities over data transferred to the United States from Facebook's European base in Ireland.
In response, the European Court of Justice on Tuesday said the 2000 "Safe Harbour" data transfer deal between the US and EU that enables those transfers was "invalid" because of concerns over privacy raised by the case of whistleblower Edward Snowden.
It said the effect is that the Irish data commissioner will now be required to examine Schrems' complaint "with all due diligence."
Once it has concluded its investigation, the authority must "decide whether ... transfer of the data of Facebook's European subscribers to the United States should be suspended on the ground that that country does not afford an adequate level of protection of personal data," the court said in a summary of its ruling.
Written with agency inputs
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