'Censorship creep': Pirate Bay block will affect one-third of U.K.
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Designed by telecommunications giant British Telecom (BT), "Cleanfeed" was used to filter out child abuse imagery, and it did so with great success.
In 2007, Home Office minister Vernon Coaker ordered all U.K. ISPs to subscribe to Cleanfeed to prevent access to scenes of sexual abuse and "criminally obscene" content.
In April 2011, the High Court in London ruled BT must block access to file-sharing site Newzbin2 at ISP level -- using none other than the Cleanfeed system. It was widely seen as a "test case" building up to forcing bigger file-sharing sites off the British Web.
Almost exactly a year later, six of the U.K.'s largest broadband providers were told by the same High Court to impose a block on their customers from accessing magnet-link sharing site The Pirate Bay.