Your private data isn’t so private

Scientists have managed to demonstrate that private data is not quite so private after tracking down individuals based on their credit card transactions and social media posts.

In research published in the journal Science, data experts looked at credit card transactions made by 1.1 million anonymous people in more than 10,000 shops over three months. The dataset, from a bank that wishes to remain anonymous, did not contain any obvious identifiers such as name, address or account numbers and the shops were distributed throughout America but it did include the date of transactions, the type of shops and the amount spent.

Researchers managed to identify 90 per cent of consumers with their data after combining the data with publicly available information such as Twitter or Instagram. "The message is that we ought to rethink and reformulate the way we think about data protection,” said lead author Yves-Alexandre de Montjoye. "The old model of anonymity doesn’t seem to be the right model when we are talking about large-scale metadata."

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