That has a logic condition, no?

Not sure what you mean - there's a pattern of dots (the EURion constellation) on the banknotes of a number of countries that photocopiers recognize and will refuse to copy.

	▲	_boffin_ a day ago \| parent [-]
		I could have been more descriptive, but yes, exactly what you described. The logic of: if i see this exact pattern, refuse to duplicate or make extremely apparent it's a fake.