Express consent for her child to take part in a trial was never gained, she said.

BBC: 'I didn't know it was a trial'

First, it is ethically-questionable whether users with public streams should be retweeting private tweets without express consent.

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For example, express consent from the individual must be obtained in connection with the transfer of personal information to any other organization.

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In Australia, facial recognition templates may soon be regulated as Sensitive Information, which will require express consent of their subject prior to collection (tagging) and not mere notification after the event.

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As Kashmir wrote, the company could have used that technique to automatically segment users into Facebook Groups, but would likely have incurred the same privacy wrath that Google faced when its Google Buzz trick exposed who users were most often chatting with without their express consent.

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The settlement requires Facebook to take several steps to make sure it lives up to its promises in the future, including by giving consumers clear and prominent notice and obtaining their express consent before sharing their information beyond their privacy settings, by maintaining a comprehensive privacy program to protect consumers' information, and by obtaining biennial privacy audits from an independent third party.

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However, if we wish to combine your personal and cookie or click stream information in this manner, we will obtain your express affirmative consent.

NEWSWEEK: Privacy Policy