Hundreds of public bodies, including local councils, can request communications data, including when and to whom e-mails are sent and phone calls made.

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Data obtained under a Freedom of Information Act request by David Patch, a well-known blogger in the movement to eradicate manipulative naked short-selling, showed an astonishingly high degree of trade settlement failures in Global Links shares in the days and weeks following a 350-to-1 reverse split in February 2005.

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For sensitive data such as telephone numbers, postal and e-mail addresses, social security numbers or financial data, a site would have to explicitly request a user's permission to track and store the information.

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The Journal obtained a limited set of Medicare data in 2010 after going through a lengthy and onerous request process usually reserved for academics conducting health-care studies.

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The data was obtained through a Freedom of Information request made by Tom Kearney, a cyclist who suffered life-threatening injuries after being struck by a bus in Oxford Street in December 2009.

BBC: London buses 'hit two pedestrians or cyclists a day'

The goods and services under inspection--including housing, transportation, food, leisure and household supplies--are representative of executive spending patterns, and the selection of the cities reflects the request for corresponding data from the groups that use the study's findings.

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