There are many creative ventures intended to support long term retention of data while still making that data accessible.

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They believe it is necessary to extend the retention of data to emails and internet traffic in order to combat serious crime, including terrorism.

BBC: Public consultation on 'web snooping' plans ends

Home Secretary Alan Johnson told the Commons that DNA profiles had had a "profound impact" in bringing criminals to justice, defending the retention of data even of people who were not convicted of a crime.

BBC: Crime and Security Bill

However, the further retention of the data should be allowed where it is necessary for historical, statistical and scientific research purposes, for exercising the right of freedom of expression, when required by law, or where there is a reason to restrict the processing of the data instead of erasing them.

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That's a pretty significant change, as the previous policy boasted data retention limits of only 90 days.

ENGADGET: Yahoo to retain search data for 18 months, says it's in your best interest

Increasing compliance requirements force longer retention of more information, regulating the amount of data that needs to be stored.

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For Google, which holds more than 70% of the search-engine market by some counts, data retention is one area where the company may be vulnerable.

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Many factors are at play here dealing with individual or third-party data retention policies sometimes beyond your control as well as continued usage of the same private encryption key and password.

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More important, it trumps Google's own bid to reassure users of their privacy: In September, the search giant cut its data retention period from 18 months to nine months.

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