The Limitations of a Counterfeit Pen

| 25 Apr 2017

The Limitations of a Counterfeit Pen

Every year, millions of "fake" notes are passed over retail counters. The majority are not identified as counterfeit until they're examined by a bank.

Often retail staff aren’t trained on how to tell the difference or they rely on the simplest of all anti-counterfeiting tools; the counterfeit pen.  Unfortunately, relying on the pen alone is not going to catch anyone other than an amateur, printing money on a laser printer.

It’s Not Magic!

Counterfeit pens contains a tincture of iodine as ink which, when drawn over a legitimate note, will make a temporary amber mark. 

The iodine will react with any starches present in the paper.

Starch is the primary component used to make white paper look brighter. Most commercial paper, made from wood pulp, is brown unless bleached and starched. 

If there is starch present in the paper then the mark will be dark brown or black and will not fade, indicating that the note is suspicious.

The problem with relying on the pen alone is that sophisticated counterfeiters may not use paper that contains starch. Instead they may obtain or replicate paper that is made from cotton fibres like those used in genuine currency, worldwide.

One method that has been used to obtain "legitimate" paper is to wash a small denomination banknote in bleach and use the resulting paper to print a larger denomination banknote.  When a counterfeit pen is used on one of these notes it will appear as legitimate.

Another method is to obtain actual currency paper.  While this is not usually an available option for the average counterfeiter, large scale operations often do have access to starch free cotton fibre paper.

Common Sense Is Required…

It is vital that you know the limitations of any devices you are using to detect counterfeit currency and it is advisable not to rely on only one method.

It is also imperative that anyone handling cash in your business is familiar with the security elements of the notes they are handling. More information on the latest design and security features of Euro banknotes can be found at

Ultra Violet lights are also a widely used counterfeit detection method but it is has been found recently that counterfeiters are painting sun block type solutions on the fake notes to ‘fool’ the bulbs.

The goal should be to put as many obstacles as possible between the counterfeit note and your back office.

So What Should I Buy?

The most effective counterfeit detection strategy is one that employs multiple detection methods.

Our compact and inexpensive Motorised Currency Detector uses ICD (Intelligent Code Detection), IR (Infrared), and MG (Magnetic Ink) & MT (Magnetic Thread) to identify counterfeit notes; each of which are explained in more detail below.

Motorised Currency Detector


This technology determines whether money is genuine or counterfeit by searching for a code hidden inside the security thread of a banknote. To find the security thread of the ES2 note without an ICD machine, look at the banknote against the light. The security thread appears as a dark line. The € symbol and the value of the note can be seen in tiny white lettering in that stripe.


Infrared is essentially invisible to the human eye. Paper money with Infrared Ink (IR) requires a scanner which can render IR visible to the human eye. Under infrared light, on the front of the ES2 banknote, only the emerald number, the right side of the main image and the silvery stripe are visible. On the back, only the value numeral and the horizontal serial number are visible.


Some Central Banks use ferromagnetic Ink in the serial number of their currency along with a magnetic thread woven throughout the paper. A magnetic detection machine enables the cash handler to identify the authenticity of money by scanning for traces of magnetic ink in the letterpress and magnetic thread patterns throughout the banknote.

Sources: |

Share This...

Back to news listings

Latest News

For Cash Handlers In All Sectors

Latest articles

See all news articles

Subscribe Now

The latest news - direct to your inbox; counterfeit note alerts, cash handling case studies, product & industry news and notifications on new ECB banknote releases.