Huh. I have a crappy home scanner/copier/printer thing that does that… I didn’t realize that was the reason it happened, but it makes sense. (And thinking back, it did only happen with photocopies, not with print outs.)
At my last job we had these awesome color laser printers. Just to test, we copied a 20 dollar bill and it came out really really well. The only thing that flagged that it was not real was that the dichroic ink did not copy correctly. But, otherwise, it was so well made that we panicked and shredded it.
Maybe, the printer would have rejected the old older type, like from the 80s. Or, it would have reproduced it super awesome.
Responses suggest that there’s no regulation of scanners or printers, just copiers. This agrees with my vague memories from working at the company which made copiers, scanners and printers.
… And confirms that the Secret Service’s concern isn’t people with savvy, just teenagers stopping at Kinko’s to make some quick bucks! 
:smack:
My brothers friend worked at Canon years ago when colour laser copiers were just new. He copied a $5 bill on one side only. He cut it out and stuck it in his wallet to show friends. I saw it and it looked good if you only looked casually. It was on regular bond paper and didn’t feel right and was too white to be a real note, but the image of the face of the bill was really good.
At the end of the night he realized that he spent it by mistake at a movie theatre.
Or you could flush it and hopefully not clog the toilet.
Hope your friend appreciates the bullet he dodged there. The Secret Service does not make exceptions for ‘I was just kidding around’, counterfeiting like that is a Federal offense. If he’d been caught best he could hope for would be like a 1-year suspended sentence. And a felony conviction on his record.
I just realized that I’ve had a Brother all-in-one machine for over two years and never tried scanning money. Just doing it now, I don’t get any threatening messages, but the scanner will only scan half the bill. Actually, the scanner head goes the full way across, but only half the bill’s picture appears. Tried it few different ways, it definitely ‘knows’ its scanning currency!
Gotta go, someone is pounding on my door… 
I’ve just tried to copy a £10 note on our office copier/scanner (a Canon).
This is the image that it produced:
So it will allow the scan to take place but it disrupts it to the point where it’d be useless to any would-be currency faker.
And even when I tried to open this disrupted image in Adobe Photoshop I still got an error message saying:
Something odd considering this, I went to Wikipedia and they have high resolution images of US currency! Didn’t save one and see if my printer would print it, I still don’t have a shredder!
You don’t need a shredder. Just cut the paper with scissors one way, then turn the paper 90º and cut it again into tiny squares. A bit more work but it shreds.
Or take a match to it.
Even the microprint comes out clearly.
Well I remembered that my dad has a shredder, so I saved the Wiki 5MB image of a $10, had to do a little math to shrink it to the right size with MS Paint, and sent it to my printer. Did the same thing as when I tried to scan it, it only printed the top 50% of the image. No warnings or sirens, but still kinda neat that it can detect this.
Just have to get an eeprom writer and desolder its firmware chip and reverse engineer the code out of it!
nm
At my work we have a large Toshiba machine much like the one pictured here: http://www.nsditoshiba.com/images/estudio4520c.jpg
When they came to install it, the techie gave us a speech on copying banknotes, with the dire warning that any attempt to do so will result in the machine locking up and having to be reset by a factory-appointed specialist.
I’ve never felt brazen enough to test this…
We actually do work with photocopies of currency; when cash is seized from a drug bust, or when cash will be used to do a drug buy with a confidential informant, the cash is photocopied so that it can be positively identified later. Of course, we make the photocopies in black and white, and they come out fine, so either the PD has an older copier, or the black and white copying doesn’t trigger the anti-counterfeiting circuits.
Well, in the interests of increasing knowledge, I just tried it. It stops at 50% of the bill if I scan in color or even greyscale! Only if I choose Black & White will it show the whole bill!
What kind of a fascist police state do we live in!?!
How exactly is this supposed to help? I print out the currency, and then what can I do with it? The paper is thicker, the stuff in the middle is different. And here’s a big one–the grain is clearly printed on, not actually in the paper.
At least the dithering fingerprints make sense–making all printouts trackable to a specific device. But this? It sounds like restrictions from people who didn’t really know what they were doing.
Pass it on to someone lacking in common sense (i.e. most people). If you can photocopy currency then it becomes easy to make lots and lots of small denomination notes which cashiers won’t bother to examine closely. “These feel funny!” - “They’re brand new” - “Oh. OK”.