Warning - our printer has a watermark

Martin · Post by **Martin** » Sun May 11, 2008 8:57 am

This may be of concern to some users of our printer.

Like many color printers, ours prints a hidden watermark with the time, date and serial number of the printer.

This watermarking system was developed to help trace counterfeiters, but the encoding has now become public knowledge, which means that in theory anyone - not just some shadowy government agency - with the right equipment and some time could identify the printer your document came from and when it was printed.

Some general information on this from the EFF:

http://www.eff.org/issues/printers

What the watermarks look like and how to interpret them:

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

List of printers that are known to do this or not:

http://www.eff.org/pages/list-printers- ... cking-dots

Ours is a Konica/Minolta Bizhub C252.

swithun · Post by **swithun** » Sun May 11, 2008 10:31 am

That's good to know. I'll have to print my yellow bank notes somewhere else.

chombee · Post by **chombee** » Mon May 12, 2008 1:03 pm

Maybe print out the EFF info and stick in on the printer as a warning.

martinmckenna · Post by **martinmckenna** » Mon May 12, 2008 3:10 pm

maybe just make posters with only the dots , can you get uv toner ?