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Government Uses Color Laser Printers to Track Documents.
From: Feher Tamas <etomcat () freemail hu>
Date: Tue, 23 Nov 2004 21:32:58 +0100 (CET)


Government Uses Color Laser Printer Technology to Track
by Jason Tuohey, Medill News Service, 22 November 2004

Practice embeds hidden, traceable yellow data in every page

Next time you make a printout from your color laser printer,
shine an LED flashlight beam on it and examine it closely
with a magnifying glass. You might be able to see the small,
scattered yellow dots printed there that could be used to
trace the document back to you.

According to experts, several printer companies quietly
encode the serial number and the manufacturing code of their
color laser printers and color copiers on every document
those machines produce. Governments, including the United
States, already use the hidden markings to track counterfeiters.

Peter Crean, a senior research fellow at Xerox, says his
company's laser printers, copiers and multifunction
workstations, such as its WorkCentre Pro series, put the
"serial number of each machine coded in little yellow dots"
in every printout. The millimeter-sized dots appear about
every inch on a page, nestled within the printed words and

"It's a trail back to you, like a license plate," Crean says.

The dots' minuscule size, covering less than one-thousandth
of the page, along with their color combination of yellow on
white, makes them invisible to the naked eye, Crean says.
One way to determine if your color laser is applying this
tracking process is to shine a blue LED light--say, from a
keychain laser flashlight--on your page and use a magnifier.

Crime Fighting vs. Privacy

Laser-printing technology makes it incredibly easy to
counterfeit money and documents, and Crean says the dots, in
use in some printers for decades, allow law enforcement to
identify and track down counterfeiters.

However, they could also be employed to track a document
back to any person or business that printed it. Although the
technology has existed for a long time, printer companies
have not been required to notify customers of the feature.

Lorelei Pagano, a counterfeiting specialist with the U.S.
Secret Service, stresses that the government uses the
embedded serial numbers only when alerted to a forgery. "The
only time any information is gained from these documents is
purely in [the case of] a criminal act," she says.

John Morris, a lawyer for The Center for Democracy and
Technology , says, "That type of assurance doesn't really
assure me at all, unless there's some type of statute." He
adds, "At a bare minimum, there needs to be a notice to

If the practice disturbs you, don't bother trying to disable
the encoding mechanism--you'll probably just break your printer.

Crean describes the device as a chip located "way in the
machine, right near the laser" that embeds the dots when the
document "is about 20 billionths of a second" from printing.

"Standard mischief won't get you around it," Crean adds.

Neither Crean nor Pagano has an estimate of how many laser
printers, copiers, and multifunction devices track
documents, but they say that the practice is commonplace
among major printer companies.

"The industry absolutely has been extraordinarily helpful
[to law enforcement]," Pagano says.

According to Pagano, counterfeiting cases are brought to the
Secret Service, which checks the documents, determines the
brand and serial number of the printer, and contacts the
company. Some, like Xerox, have a customer database, and
they share the information with the government.

Crean says Xerox and the government have a good
relationship. "The U.S. government had been on board all
along--they would actually come out to our labs," Crean says.


Unlike ink jet printers, laser printers, fax machines, and
copiers fire a laser through a mirror and series of lenses
to embed the document or image on a page. Such devices range
from a little over $100 to more than $1000, and are designed
for both home and office.

Crean says Xerox pioneered this technology about 20 years
ago, to assuage fears that their color copiers could easily
be used to counterfeit bills.

"We developed the first (encoding mechanism) in house
because several countries had expressed concern about
allowing us to sell the printers in their country," Crean says.

Since then, he says, many other companies have adopted the

The United States is not the only country teaming with
private industry to fight counterfeiters. A recent article
points to the Dutch government as using similar
anticounterfeiting methods, and cites Canon as a company
with encoding technology. Canon USA declined to comment.

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