The watermarks, generally in the form of tiny yellow dots, are used in some commercial and consumer digital printers "in a purported effort to identify counterfeiters", according to consumer privacy body the Electronic Frontier Foundation (EFF).

Frattini, who is also responsible for justice, freedom and security, said that while the EC did not know of national laws governing the tracking mechanisms, "such processing may give rise to the violation of fundamental human rights, namely the right to privacy and private life".

Frattini raised the issue in response to a question from Finnish Green Party representative Satu Hassi, who said that "manufacturers have stated these measures were implemented to deter counterfeiting".

Hassi said: "Manufacturers have not publicly described how the tracking codes work or what information is coded. Recent research by [the EFF] indicates that some printers and photocopiers are coding their serial numbers and the date and time of printing into each page."

US-based EFF has compiled a list of models that output yellow tracking dots, including toner-based production presses from leading manufacturers.

EFF said the US government had been responsible for "persuading some colour laser printer manufacturers to encode each page with identifying information", and that the Secret Service could use the codes to "secretly trace the origins of non-currency documents".

---

Got a view on this article? Comment in the space below or head to the printweek.com forums to have your say.