Do (some) 3D printers produce anti-conterfeiting marks like color laser printers?
Color laser printers do print anti-conterfeiting marks (small yellow dots) on every printed page:
https://en.wikipedia.org/wiki/Laser_printing#Anti-counterfeiting_marks 
They do this since end of the 80s, but that became known publically only 2004.
I doubt that 3D printers do similar, but thought that I can just ask.
Something not in gcode, but added by printer firmware.
Of course open source firmware would allow this to be detected, so maybe on closed firmware 3D printers?
RE: Do (some) 3D printers produce anti-conterfeiting marks like color laser printers?
You know, I've actually wondered this myself, but I'm inclined to think it doesn't happen.
I don't know of any other mechanism on the printer to produce a mark or leave material in such a manner that it would be difficult to detect, and escape notice from those who are familiar with the code for driving the printer and resultant g-code processed by the machines.
Aaron
RE: Do (some) 3D printers produce anti-conterfeiting marks like color laser printers?
There is at least one company with a method to watermark 3d models. Maker's Muse did an episode discussing the technology.
The stated purpose was to prevent people from claiming other's work as their own, but if you put a watermark in all of the original prints any print without the watermark could be assumed to be counterfeit.
A person who never failed never tried anything new. -Einstein
RE:
I am interested in buying a printer for our office at residential structural engineer's in Australia. Please help me to find a good thing. Your help would be appreciated.
RE:
I don't think there is anything inside firmware. Marlin as open source firmware for printers, there someone would notice something like that.
If you look on the printing, printer FW cannot recognize wrong setup or problematic HW configuration. Like over/underextrusion, nozzle size or bad PID and so on. And every time you print the HW configuration change a bit (belt get more loose, PID, filament irregular diameter, skew, hot plate on bed shift, screw get more loose .... So even if there where some special marks, not much to be visible for human eye, then they would be probably hidden by printer's inaccuracy. Like I wanted to print a caliper and I had really problems to have the numbers there correctly.
For STL, if you slice it and notice the sliced model, you would see some irregular things there and after some searching (load in CAD software), you can easy remove possible hidden marks or something that looks "stupid" without even knowing that it is author's hidden watermark.
Best option would be for you to pay-share the 3D/STL model into a known webportal. And on claim copyright notice, you point that your model was like few months online before his.