Printers betray document secrets

Ian Grigg iang at
Mon Oct 25 18:19:05 EDT 2004

Ben Laurie wrote:

> This only works if the marks are not such that the identity of the 
> printer is linked to the marks (as opposed to being able to test whether 
> a particular document was produced by a particular printer).
> To be really safe, I'd suggest going somewhere without surveillance 
> cameras, buying a printer for cash, using it and then destroying it.
> Don't forget not to use your car and leave your mobile phone behind. Oh, 
> and take the RFID tags out of your clothes.

It's actually quite an amusing problem.  When put
in those terms, it might be cheaper and more secure
to go find some druggie down back of central station,
and pay them a tenner to write out the ransom demand.
Or buy a newspaper and start cutting and pasting the

In more scientific terms, is there a way to efficiently
print an anonymous paper document?  (By anonymous,
I mean a document that leaves no easy clues back to
the author.)  When creating ones anonymous political
pamphlets revealing the latest government scandal,
one might need the help of RFC 666, "how to print
anonymous pamphlets with modern printers."

E.g., something like:  acquire a HP inkjet and a
Brother laser.  Disengage the ink drying fan in the
Brother.  Print the page through the Brother then
print the same page (wet!) through the HP within 5
seconds.  For paper, use fish&chip wrap, cleaned
with sarsons and dried for 30 mins under a tanning
lamp with the UV filter removed...


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