Without trust, Microsoft thinks, nobody is going to use any cloud services, and the Snowden revelations put the trustworthiness of all technology suppliers in the spotlight. So when a warrant arrived at Microsoft’s Dublin data centre one day in 2013, a not uncommon occurrence for a cloud host, Microsoft was ready to kick back.

What Microsoft has done is refuse to comply, putting itself voluntarily in contempt of court. At issue is a piece of legislation called the 1986 Stored Communications Act, and the software firm is challenging two key things about it. Firstly, that the act covers private data that happens to be stored on your behalf by a third party (in this case Microsoft). Microsoft argues that the personal data is not its own, much as a UGC hosted YouTube argues that it doesn’t own material that is “stored at users’ direction”
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“These are the private communications of our customers. They’re not ours. We don’t have access to them. We don’t want access to them,” he told an audience this week. “That’s a very different position to saying that any data stored with a cloud provider is a business record of that cloud provider, that can then be turned over to the government. That is a very dangerous precedent.”

And an interview with The Register clarified that point further: “By design we tell customers it is yours, we’re not going to access your data.”

Source: Microsoft legal eagle explains why the Irish Warrant Fight covers your back