
"The Court of Justice declares that the (European) Commission's US Safe Harbour Decision is invalid," it said in a decision on a case brought against Facebook by Austrian law student Max Schrems.
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The court said Irish authorities now had to decide whether transfer of data from 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 complaint focuses on the "Safe Harbour" deal signed in 2000 between Brussels and Washington that allows data transfers by thousands of businesses on the grounds that US laws offer similar protection to those in the 28-nation European Union.
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Schrems, a right-to-privacy campaigner in his native Austria, filed the case against Ireland's data protection authority because Facebook's European headquarters are based there.
He had argued that the 15-year-old Safe Harbour deal is too weak to guarantee the privacy of European residents in the wake of details provided by Snowden.
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