f13.net

Just because a document from a color laser printer doesn't carry your name doesn't mean no one can trace it back to you, privacy advocates warn.

The Electronic Frontier Foundation says it has cracked the tracking codes embedded in Xerox Corp.'s DocuColor color laser printers. Such codes are just one way that manufacturers employ technology to help governments fight currency counterfeiting.

"Underground democracy movements ... will always need the anonymity of simple paper documents, but this technology makes it easier for governments to find dissenters," said Lee Tien, EFF senior staff attorney. "Even worse, it shows how the government and private industry make backroom deals to weaken our privacy by compromising everyday equipment like printers."

Researchers found patterns of yellow dots arranged in 15 by 8 grids and printed repeatedly over every color page, said Seth Schoen, a staff technologist at the San Francisco-based civil-liberties group.

The dots are visible only with a magnifying glass or under blue light, which causes the yellow dots to appear black.

By analyzing test pages printed out by supporters worldwide and by staffers at various FedEx Kinko's locations, researchers found that some of the dots correspond to the printers' serial numbers. Other dots refer to the date and time of the printing.

So why not just counterfeit currency from a different country?

Heh.  AFAIK, and my spouse worked at Xerox, and one of my good friends writes code for them, all their copiers will stop functioning if you try to copy money.  There are algorithms to detect the image of US currency which then burn out a part inside.

Cool, looks like we're going to be getting a new copier on my floor if this works.  So long, shit-box!

By disclosing this information, they're just making it harder to catch counterfeiters, a la "forewarned is forearmed".

Heh.  AFAIK, and my spouse worked at Xerox, and one of my good friends writes code for them, all their copiers will stop functioning if you try to copy money.  There are algorithms to detect the image of US currency which then burn out a part inside.

So why not just counterfeit currency from a different country?

I asked a few Xerox technicians about this today at work and they called bullshit.  They did, however, admit they don't know every single detail about every Xerox machine.  Considering all the ways around these algorithms, I don't think Xerox would waste their time on it, but I'll ask an analyst or engineer the next time they pop up around here.

Because US currency is ridicoulusly easy to copy compared to that of countries that stay with the times.
(I know there's some reason connected to State and Federal law, that prevents the US from just changing the dollar bills like the rest of us do with our currency, but I can't be arsed to look it up...)

Heh.  AFAIK, and my spouse worked at Xerox, and one of my good friends writes code for them, all their copiers will stop functioning if you try to copy money.  There are algorithms to detect the image of US currency which then burn out a part inside.

IIRC, You can't manipulate images of US currency using Photoshop either.  There are guidelines and restrictions on how you can use color images of money though, but the software seems to prevent even legit uses.