A privacy group says it cracked the code used by color printers to leave an identifying watermark on documents that can be traced by the U.S. government.
Cyber sleuths at San Francisco's Electronic Frontier Foundation announced this week that the virtually invisible lines of tiny yellow dots laid down on a page identify not only the individual printer but the date and time the document was printed.
The tracking system was devised to allow the Secret Service to track down currency counterfeiters; however, the foundation warned that the technology could be used as well to identify users who print flyers or other documents critical of the government.
"Even worse," said EFF Attorney Lee Tien, "it shows how the government and private industry make backroom deals to weaken our privacy. The logical next question is: what other deals have been or are being made to ensure that our technology rats on us?"
The foundation said it had only unraveled the code on the Xerox DocuColor printer but knows it exists on machines from other manufacturers.
Copyright 2005 by United Press International
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