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Some can, not all. Also, many printers are cheap, so if you are worried about this just buy them used and change them periodically. Good luck tracking someone down who bought their printer off Craig's list or at a pawn shop.

Older printers don't add identification to printed pages. I don't remember the exact year but I think the rule of thumb is that anything from the 80's or older is safe.

Also, it's notoriously hard to obtain a copy of a printer's driver source code.

Time to hoard type writers?