<< Imagine that every time you printed a document, it automatically included a secret code that could be used to identify the printer – and potentially, the person who used it. Sounds like something from an episode of "Alias," right?

Unfortunately, the scenario isn't fictional. In a purported effort to identify counterfeiters, the US government has succeeded in persuading some color laser printer manufacturers to encode each page with identifying information. That means that without your knowledge or consent, an act you assume is private could become public. A communication tool you're using in everyday life could become a tool for government surveillance. And what's worse, there are no laws to prevent abuse. >>

http://www.eff.org/issues/printers
http://w2.eff.org/Privacy/printers/docucolor/

It is not new. I even seen it once on CSI:Miami ^^

This has been the case with colour photocopiers for at least 20 years.

I really wonder what pressure or inducement is applied to the photocopier or printer makers. Why don't they just say "no"? After all, the coded dots are reducing the quality of their product's output, so they must be getting something in return.

> I really wonder what pressure or inducement is applied to
> the photocopier or printer makers. Why don't they just say "no"?

Sometimes tech companies will just do whatever is requested of them and often also only care about the revenues (and the quality difference may not be an issue with most consumers, privacy notwithstanding).
Maybe the problem is the government applying such rules or the laws allowing the gov't to do so... maybe people should ask to amend those.

Well the printed copy doesn't automatically identify John Doe as the owner of the printer. The authorities just know that an HP OfficeJet XX printed the document. No where does it have your name included.

Colin There is also an unique serial number ;)

There are serial numbers in lots of things we do these days. Like posting digital photographs onto public websites. Most digital cameras save their serial numbers to each photo taken. This still doesn't point to a specific person UNLESS you register your products with the company that made it. Product registration is not mandatory, its more of a way for the companies to gain more personal information on all of their customers which they can turn around and sell to 3rd party companies anyways.

> Maybe the problem is the government applying such rules or the
> laws allowing the gov't to do so... maybe people should ask to
> amend those.

As far as I know, there is no law requiring this. Some government department asks the printer manufacturer, and for some reason the printer manufacturer agrees. I'm just wondering if some kind of "behind-the-scenes" inducement is offered.

A related technology prevents copying currency notes issued by the US, the UK, the Euro, and some other countries. The currency notes have a pattern of dots in some mathematically-significant spacing (squares-of-the-integers I think). A colour photocopier detects this and won't print it. Certainly the Xerox colour photocopiers implement this.

Something similar is in some software too. Try loading an image of US currency into Photoshop or Paint Shop Pro – you'll get an error message saying that it doesn't support the unauthorized processing of banknote images. (But it works in open-source software such as Gimp).

A computer program called Eurionize lets you add the anti-copying pattern to a PostScript document of your own.

More details:
http://en.wikipedia.org/wiki/EURion_constellation

Printers, encode a serial Number

Adobe photoshop, will change slightly the colors

The press release of EFF is extremely old...