The Irish Council for Civil Liberties is suing a branch of the Interactive Advertising Bureau (IAB) and others over what it describes as “the worlds largest data breach”. The IAB Tech Lab, whose members include Facebook, Google and Amazon, which is based in New York, develops digital ad industry standards.

The case brought by Johnny Ryan centres on the data shared between ad brokers and other firms while ad space is being auctioned as a site loads.

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