DA XEROX CODE
Early in 2005, Internet Archive founder Brewster Kahle noticed something a little weird about the color copies he was making. When he looked at the pages really closely, he could see hundreds of tiny yellow dots — and they looked like they formed some kind of pattern. He recalled seeing an article in PC World about how the Secret Service busted counterfeiters by using marks on the fake bills that could be traced back to the printers that made them. If these dots were a method of tracking, then Kahle wanted to know exactly what information they contained.
He turned to Electronic Frontier Foundation technologist Seth Schoen for answers. Schoen, with the help of EFF intern Robert Lee, combed through hundreds of pale-yellow-speckled color
Xerox research fellow, who confirmed their worst suspicions: yes, the dots were for tracking. How widespread was this practice? Was it just Xerox?
To find out, Schoen posted a call for color copies on the EFF website. He soon received hundreds of printouts from all over the world. “One was from an ice cream parlor in Australia,” he recalls. “Another was from a symphony orchestra.” All of them had the telltale yellow dots.
It turned out that companies like Dell, IBM,
Canon, Lexmark, Toshiba, and many others were
creating the dots on color laser printouts (for a
list of printers that gen-
erate tracking dots, see Barely visible dot-matrix
eff.org/Privacy/printers/ “fingerprints” enable
list.php). Schoen specu- any page to be traced
back to its color printer.
References:
Archives