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UV Verification of the $100 Bill

Many of our customers ask us - Why is the UV security feature on the $100 bill more difficult to see than it is on the other denominations?

It is a good question, and one which users of the FraudFighter™ line of UV currency detectors have asked for years.1 bill image

To give a little background, in 1996, the Bureau of Engraving & Printing (BEP) released the first major redesign of the US currency in decades.  The redesign was conducted in order to combat a rising tide of high quality counterfeit dollars produced by “off-set” printing techniques. The new design were often called “big heads” by collectors and others in the field due to the fact that the portrait of the U.S. historical figure depicted on the banknotes were increased in size by more than 400% from the previous design.  When compared side-by-side, the difference is immediate and apparent.100 bill image

At the time this redesign was performed, a number of new security features were introduced.  We have covered these features in an earlier post. Among the security features added was to introduce UV $50 Security Thread Magnifiedfluorescence into the security strip, a thin Teflon strip built into the currency paper.  The security strip is visible when viewed with a light bulb held behind the bank notes.  You can see the security strip, with repeating  micro-printed text “USA $100” on the $100 bill, “USA $20” on the twenty dollar bill, and so on.

The Teflon strip had been added to the bills in 1988 when the BEP did a minor redesign of the notes.  Unfortunately, crafty forgers learned a variety of different techniques to replicate the strip.  In some cases, clever printing could give the appearance that a strip was present. In other cases, counterfeit paper stock was created with a darker material inserted to create the illusion of a security strip.

In order to overcome this, during the major 1996 redesign, the BEP added a new element to the security strip.  During the process of producing the strips, an ultra-violet fluorescent compound was added to the chemical mix.  This compound, when exposed to long-wave (ca. 375 nanometer) UV light, will fluoresce, or “glow” a unique color.  Each new banknote denomination was created so that the security strip inside the note would glow a different color – red for $100, yellow for $50, green for $20, and so on.

UV fluorescence US dollar

For each of the denominations, this glowing thread inside the bill is clearly visible and easy to see – with the notable exception of the $100 bill. For reasons that have never been made clear (despite directly asking the chief designer of the $100 bill at the Bureau during a tour of the facility by yours truly!) the glowing feature in the $100 bill is not as clear or as bright as the other denominations.

Conspiracy theories abound as to why this may be the case.  Most of them center around the concept that, perhaps, for some reason, our government never really intended for the $100 bill to be secure. 

We believe it was simple design flaw, although, one has to ask the question – why has the problem not been fixed during the 16 years since the original production run of the new $100 was made?  It couldn’t have been a difficult fix…..

Regardless of the reason, the fact is that the security strip in the $100 can be difficult to see, even under the most powerful UV counterfeit detector available, the UV-16.

Now, for some good news.

  1. The new-design $100 being released New Design $100 bill“sometime soon” does have an improved fluorescent strip. We know because we have been given samples of the bill and have viewed them under one of our UV-16 machines.
  2. The current $100 bill can be verified by checking the paper upon which the bill is printed.  Genuine US banknotes are printed on “UV-dead” paper, which does not reflect UV light.  Counterfeit notes will usually reflect the UV light, thus, counterfeit money will “glow” blue as it reflects the UV light back to your eyes.  One way to verify that is to take a known good bill – we recommend a $5 bill – and hold it next to the suspect $100.  If you see the $100 having a blue glow to it that is the first sign it is probably counterfeit.
  3. A few years ago, Fraud Fighter™ developed a unique fluid material that makes the $100 bill strip glow more brightly.  This comes in a pen, called the UV Brite-Stik.  Just swipe the fluid in the pen across the strip, then view under the UV-16 or other Fraud Fighter model, and that strip becomes a bit easier to see.
Counterfeit Currency Detection Whitepaper