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2
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3answers
326 views

How can U.S. prevent counterfeit if the U.S. dollar bills have no expiry date? [closed]

Counterfeit bills are a big problem for governments, so they periodically update their bills to add several security features aimed at preventing counterfeit bills. But I imagine that for this to ...
4
votes
1answer
457 views

Is the $5 USD bill from Series 2006 supposed to glow brightly under ultraviolet?

So my company just changed offices recently and for some odd reason or another the server room in the new building has a black light which was installed by the previous tenants. Aside from the oddity ...
39
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5answers
17k views

How common is counterfeit money in circulation?

I've noticed recently that several places where I paid with a $20 bill, the cashiers used a small marker to detect whether the bill was counterfeit or not before accepting it. Like so: I saw this ...