PMG Counterfeit Detection: Altered Serial Numbers on Chinese Notes

Posted on 3/16/2021

A recent submission to PMG included three notes whose fancy serial numbers were not genuine.

In paper money collecting, a fancy serial number can greatly add to the value of a banknote. Indeed, for many modern notes, the only elements that can add value are a fancy serial number or an error.

There are different types of fancy serial numbers. They include “solid,” in which the serial number contains the same repeated digit; “ladder,” in which each successive digit within the serial number increases or decreases by one; and radar, in which the serial number is the same forward as it is backward. (You can learn more about fancy serial numbers here.)

PMG attributes qualifying fancy serial numbers on the certification label. Before PMG does that, however, the grading team checks to make sure the entire note, including the serial number, is genuine. PMG recently received a submission that included three notes with altered serial numbers.

An altered China 2005 5 Yuan (Pick #903b) and two examples of an altered China 2005 100 Yuan (Pick #907b).
Click images to enlarge

At first glance, each of these notes appears to have what is called a “Super Radar Serial Number,” which includes the numbers from the red prefix. Like other fancy serial numbers, this would bring a numismatic premium.

Close-up of the serial number on each altered note.
Click images to enlarge

But take a closer look at the digits in each series number. Do any of them seem slightly wobbly or uneven?

The serial numbers on a genuine China 2005 100 Yuan (Pick #907b) and a genuine China 2015 100 Yuan (Pick #909), which shows an updated style for the digits.
Click images to enlarge

The font used for the serial numbers in the altered notes would make it easy for a counterfeiter to turn the digit 3 into the digit 8. Compare these digits to a later generation of Chinese currency. You can see the 3 now has a flat top, while the 8 does not.

Two of the altered serial numbers under special lighting.
Click images to enlarge

The PMG team often examines elements of a banknote under special lighting during its authentication process. In this case, special lighting had no effect on the serial numbers. But when we use high magnification, the deception is a little easier to see.

High magnification of the altered digit in each serial number.
Click images to enlarge

In each, the width of the 8 appears uneven in the places where ink was added to the original 3. In addition, there is a subtle difference between the shade of the original serial number ink and the ink added by the counterfeiter. After using image editing software to significantly increase the exposure of the images, the location of the added ink becomes clearer.

Close-up of altered digit in each serial number, with increased exposure.
Click images to enlarge

Eight is considered a lucky number in China because its pronunciation sounds similar to that of the word "wealth" — this forger may have attempted to turn these 3s to 8s to make the notes more desirable. Remember: Any banknote certified by PMG is backed by our PMG Guarantee of grade and authenticity.

By the way, if you like fancy serial numbers, PMG features them every Friday on its Facebook, Twitter and Instagram pages. Find links to them and learn how to receive PMG's free monthly newsletter via email at

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