http://www.chron.com/cs/CDA/ssistory.mpl/nation/3403012
WASHINGTON - It sounds like a conspiracy theory, but it isn't. The pages coming out of your color printer may contain hidden information that could be used to track you down if you ever cross the U.S. government.
Last year, an article in PC World magazine pointed out that printouts from many color laser printers contained yellow dots scattered across the page, viewable only with a special kind of flashlight. The article quoted a senior researcher at Xerox Corp. saying that the dots contain information useful to law-enforcement authorities, a secret digital "license tag" for tracking down criminals.
The content of the coded information was supposed to be available only to agencies looking for counterfeiters.
Now, the secret is out.
Tuesday, the Electronic Frontier Foundation, a consumer privacy group, said it had cracked the code used in a widely used line of Xerox printers, an invisible bar code of sorts that contains the serial number as well as the date and time a page was printed.
With the Xerox printers, the information appears as a pattern of yellow dots, visible only with a magnifying glass and a blue light.
The EFF said it has identified similar coding on pages printed from nearly every major printer manufacturer, including Hewlett-Packard Co., though its team has so far cracked the codes for only one Xerox model.
The U.S. Secret Service acknowledged that the markings, which are not visible to the human eye, are there. "It's strictly a countermeasure to prevent illegal activity specific to counterfeiting," agency spokesman Eric Zahren said.
