Color printers include back door for Secret Service

Color printers include back door for Secret Service

Summary: Many color laser printers spray an invisible pattern of dots that lets the U.S. Secret Service identify which printer produced the print. It's an anticounterfeiting measure with serious privacy ramifications.

TOPICS: Printers, Hardware

Concerned that color laser printers could be used to produce counterfeit currency, the Secret Service secretly worked with printer manufacturers to include a code that identifies the date and time of every printout, as well as the printer's serial number, the Electronic Frontier Foundation reports

EFF worked with printouts from Xerox DocuColor printers to discover the meaning of a pattern of hard-to-see yellow dots produced by the printes. "We've found that the dots from at least one line of printers encode the date and time your document was printed, as well as the serial number of the printer," said EFF Staff Technologist Seth David Schoen. EFF provides details and a program for decoding your own printouts:

You can see the dots on color prints from machines made by Xerox, Canon, and other manufacturers (for a list of the printers we investigated so far, see: The dots are yellow, less than one millimeter in diameter, and are typically repeated over each page of a document. In order to see the pattern, you need a blue light, a magnifying glass, or a microscope (for instructions on how to see the dots, see:

The Secret Service denied the agency is interested in tracking users, according to the SF Chronicle. "It's strictly a countermeasure to prevent illegal activity specific to counterfeiting," agency spokesman Eric Zahren said. "It's to protect our currency and to protect people's hard-earned money."

Topics: Printers, Hardware

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  • Money

    I find this mildly disquieting.

    While I deplore counterfeiting; I'm not so sure I want Uncle Sam to be tracing who printed what from what printer. It might work well for tracing notes involved with kidnapping, ransom, extortion, blackmail etc. But it also opens the door for them to trace political commentaries, activist, lobbyist, and dissenter activity. And tracing is only one step removed from monitoring; which can lead to manipulating or suppressing.
    • RE: Money by Dr_Zinj

      Boy, you said a mouthful!!! I'm with you.

      While counterfeiting MAY be a problem for SOME, there ARE extremely simple ways of identifing counterfeit money. There are waaaaay toooooo many builtin features of the original bill that simply can NOT show up on a copied bill even WITH a laser printer. I know this because as a Black Jack Dealer for a local casino we all had training by the FBI itself on how these built-in features can be seen as well as by the way the paper feels to the touch.

      I feel that you are particularly correct in that "it also opens the door for them to trace political commentaries, activist, lobbyist, and dissenter activity. And tracing is only one step removed from monitoring; which can lead to manipulating or suppressing." It's just another way The First and Fifth Amendments of the Constitution of the United States is being ignored, trampled and destroyed.
    • YEAH.........................

      What Doc said
  • Old news...

    EFF has been talking about this for several months already. They have pages you can print to examine for the marks, and they ask that you send printed pages to them with your printer type and serial number for their database. They have begun a list of printers that use this technology...
  • Color Copiers and Yellow dots.

    Interesting that EFF has just picked up on this. I am a color copier technician, and this practice has been going on for years now with color copiers. The yellow dots giving the serial number of the copier has been in place for at least five years, or more.

  • Colour printers

    While I value my privacy, stiffing a merchant because I accidently picked up a counterfeit bill as change or a payment from someone else.
    The merchant is the one who loses the money because the bill is counterfeit is not something most of do not want to do.
    So do we all need to buy a machine that detects bad bills?
    No, because then it would be our loss. Some merchants already have bad-bill detectors installed at each checkout location. And all that causes us to avoid using cash, even for our kids' weekly allowances.

    So, dots on colour copiers is a way to protect us all from bogus bills. There is no way that any government agency can look at billions of pieces
    of paper. And we can still use black and white for our secure items or ink-jet colour printers for our own documents.
    • Might Not Be Your Loss

      for many folks, homeowner's insurance will reimburse them for counterfeit currency that might happen to come their way.

      mark d.
      • Maybe, but at what cost?

        These days, most of us have cranked up the deductible on our
        homeowners (or renters) insurance to try to keep the premium
        down--so it becomes catastrophe insurance, not something to
        use for a fake $100 bill.

        Worse, there is a lot of press about insurance companies "firing"
        customers after any claim, or only a couple of claims, by simply
        denying them coverage. Then you face a surcharge premium at
        the next company because the industry database shows you
        were denied coverage--so YOU must be a problem! Pathetic.
  • Much ado about nuthin

    Soooo, you have the Serial # of the printer, BIG DEAL! How do you find the owner of that printer if they did not register it with the MFG??

    If it is a CORPORATION and the printer is on a shared network, how do you determine WHO actually made the printout??

    What if it was made on a "Demonstrator" still sitting on the shelf in an retail store?? You are never going to be able to find out who made it then.
    • Re: Much ado about nuthin

      Dude, wake up!

      >>>Soooo, you have the Serial # of the printer, BIG DEAL! How do you find the owner of that printer if they did not register it with the MFG?? <<<

      To which distributor/reseller did the manufacturer send the printer? To who did the d/r sell that printer to? Screw registration, they can find you by tracing the route the printer took from manufacturing.

      >>>If it is a CORPORATION and the printer is on a shared network, how do you determine WHO actually made the printout?? <<<

      If they are using any version of Windows as of NT 3.51 or later, or any version of Unix, admins can tell you when and who printed anything.

      >>>What if it was made on a "Demonstrator" still sitting on the shelf in an retail store?? You are never going to be able to find out who made it then.<<<

      You're assuming that retail stores don't keep at least three years of archived in store security footage... say, like Best Buy does? My best friend is a security consultant for their security division out of the Bay area...
  • Is it April 1st already?

    As usual we get all the phobias commenting. So what if somebody can trace you? Who cares? Next we'll be getting number plates off cars in case it helps track down who mowed little Johny down as he crossed the road going to church.
    It's all about amassing specific evidence form 'a source' not about Joe Bloggs and his word doc. Anyway, all printers have the facility to 'correct' or change the serial number to anything we want (We're meant to do it every time we swap the main engine board). So sleep easy, unless they change it to the number of your machine! That would be funny.

    ps The stores in my area wouldn't take a hit.... they'd simply pass it on to the next unsuspecting mug (you or me)!
    • I agree but.

      While I agree with you this comes dangerously close to compelling a person to provide evidence against themselves. While I can see the benefit from the government's side I do question the uses such technology would actually be put to by any government.

      The fact is that any government is going to abuse the power given it. Just look at our own we've granted it only a small portion of the our personal soveriegnty and see how it invades and pervades our lives.
      • It depends on your views...

        Personally I prefer Dilberts crime busting ideas.. take DNA at birth, hoover the crime scene, get the culprit! If you've nothing to hide, they won't find it! And why the paranoia? Who is gioing to be interested in looking at my boring data for any length of time?

        Think about one thing. Suppose something happened to your kids (hopefully it wont) would you still want the goody goody lets see if there is good evidence OR (my preference) we know who did this and we're popping round to get answers. If they don't talk, or they lie, they're guilty of something. My personal view is that the crooks have too many 'get out of jail cards', 'chance cards', and the cops are forced to play blind. It's a mad situation when folk are happier to let folk off the hook rather than just ask and see if they're lying.

        I'll bet you don't treat your kids freedom/rights the way you're suggesting we treat crooks (regardless of the crime). I ask mine and I know when they're fibbing, and I let them know. They don't get smacked as they know what's right, and know they're going to be questioned. Now if they told me they wanted a lawyer or didn't answer..... I might just be tempted.
  • To all you nay sayers

    Obviously you have no knowledge of intelligence gathering; nor do you have any comprehension of real detective work.

    Sure, you'd probably object if there were one source for someone to pull up every bit of information on you for your entire life history. However, that sort of El Dorado rarely occurs.

    Intelligence work consists of gathering individual bits and peices of data to assemble into a logical pattern. One or two pixels doesn't make a picture. Nor does a screen-full of unrelated pixels make a picture. But give someone enough pixels, and a way to link them to the right spots, and then you have the picture.

    Let me toss in one more tidbit. Commercial explosives contain tracers to identify where they came from. The same thing could be done with automotive paints. There isn't any reason why Uncle Sam couldn't have toner manufacturers doing the same thing.

    So now I know the manufacturer of the printer, the serial number, where the printer was obtained from (bought, borrowed or stolen), I know when the document was printed, I know the same data about the toner cartridge, all I need to get lucky is to have the store keep security archives to pull up a photo of the purchaser(s). Did you buy with case or credit card? 9 times out of 10 the printer will be with a card. Ooo Now I know who you are, your entire credit history, where you live, etc. I can access your phone use history, your TV viewing habits from the cable company, your electrical usage, etc. I know who you are. I can trace your insurance companies to find your accidents, your health care payments, what your health problems are. (HIPAA may work okay in obstructing the idley curious or the semi-serious data gatherers; it won't stop a Cat 5 hurricane of a serious government sponsored investigation.)

    Ah, but we all know that all the cops are good honest people. They'd never arrest an innocent person. (How many innocent people were released from death row last year?) So are our politicians. (I never had sex with that woman. We'll get those weapons of mass destruction.) The FBI would never make a mistake. (Who was that innocent woman they shot at Ruby Ridge? Who was that doctor from Oregon accused of bombing the Madrid train?)

    No, you sheep can just keep your heads down. Let the wolves tell your where to go, what to do, how to do it. I hope you enjoy being sheared every year; and butchered when you're no longer of any use to those in power.