The court ruled that the US government cannot force Microsoft to give it access to its foreign servers. The justice department was demanding access to an Irish server of the company, as part of a drugs case investigation.
Microsoft, which was supported by Amazon, Apple and Cisco, said the ruling meant that people could trust cloud computing services (storing data and programs using the internet).
Data privacy groups have also celebrated the ruling. Myles Jackman, the legal director of the Open Rights Group, which campaigns for digital rights said that as a consequence, US law enforcement agencies must respect European citizens digital privacy rights and the protection of their personal data.
Microsoft had said that if the appeals court backed the government, it could result in other countries trying to accessUS-backed servers, leading to an erosion of global data privacy rights.
The justice department can still appeal the verdict, which would push the case up to the Supreme Court.
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