The Electronic Frontier Foundation and other privacy advocates have long warned that some color laser printers produce a nearly invisible grid of yellow dots on documents that store the serial number of the printer and the date stamp of the printed page. Now Benjamin Mako Hill and other members of MIT Media Labs' Computing Culture research group have established seeingyellow.com to spotlight this practice as an incursion on the civil liberties of the users of the laser printers. The yellow-dot "watermark" allows the US Secret Service to enlist the help of the manufacturers in tracking counterfeit currency generated on laser printers. A statement on seeing yellow.com calls this practice a "direct attack on the privacy of the owners and users of printers, and in particular, on their right to free, anonymous speech."
The Electronic Frontier Foundation previously reported on this issue and has posted a DocuColor Tracking Dot Decoding guide that explains how the Xeroc DocuColor model printers produce the yellow dot pattern. It also provides a utility for translating your particular dot pattern to determine what information it stores. The DocuColor pattern is a repeating 15 x 8 grid of yellow dots on the entire page that encodes up to fourteen 7-bit bytes of data, such as model number, serial number, and date of printing. Other manufactures such as Brother, Hewlett Packard and so on also produce similar tracking patterns.
On his blog Mako points out that "The Federalist Papers were one of the most important set of documents in early US political history and they have fundementally shaped the way the US and its governments grew. They were (originally) published anonymously and there's reason to believe that they would have said what they did or even been published at all if were immediately traceable to their authors."
Alexander Hamilton co-authored the Federalist Papers, before being blackmailed by James Reynolds for having an affair with his wife, Maria Reynolds. Mr. Reynolds was later arrested for counterfeiting.