A research team led by the Electronic Frontier Foundation (EFF) recently broke the code behind tiny tracking dots that some color laser printers secretly hide in every document.

The U.S. Secret Service admitted that the tracking information is part of a deal struck with selected color laser printer manufacturers, ostensibly to identify counterfeiters. However, the nature of the private information encoded in each document was not previously known.

"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.

According to this page, the Secret Service was the only organization that has the ability to decode the information in the dots. That means that its usage is (was?) limited to investigations on counterfeiting operations and threats against government personnel. That's the only stuff that falls under the Secret Service's jurisdiction.

I would be curious if the FBI has the ability to use this encoding system in investigations. I'd find it strange if they couldn't. Now that the information about how its encoded is public knowledge, its arguable that any government investigative agency could use it. Once the serial number of the printer is obtained, who it was sold to is just a subpoena ot two away.

EFF Breaks Secret Tracking Code in Color Printers