Ink-stained banknotes (IBNS)

Intelligent banknote neutralisation systems (IBNS) are used in anti-theft devices such as in cash machines (ATMs) or in safes in cash transportation vehicles. Their purpose is to prevent theft or unauthorised access to banknotes. When a robbery is attempted or actually carried out, the banknotes are deliberately damaged to make stolen banknotes unusable and worthless. This serves to reduce the risk for retailers, banks and other professional users of cash of becoming victims of crime, and contributes to greater security and confidence in the system of banknote administration.

How can you recognise banknotes damaged by an IBNS?

Various technologies are used within the IBNS. One of the most common involves system that soak security ink into the banknote and leave traces, while a less common method is bonding system that use strong and permanent glue to bond the banknotes into a solid block.

Ink-stained banknote

The use of security ink ensures that banknotes marked by the activation of the IBNS can be easily identified. The security ink soaks into the banknote and leaves traces. The ink usually flows from the edges towards the inner part of the banknotes and leaves a characteristic pattern (waving effect). The original colours of the most commonly used security inks are purple, green, blue, red or black. 

Sometimes criminals try to wash off the banknotes, but such attempts are usually unsuccessful. They use chemicals that should remove the security ink, but usually they just reduce it or change it to a different colour. Often, attempting to remove the security ink will result in damage to the banknote's security features.

IBNS ink-stained banknotes have a recognizable color and pattern of staining. Do not accept such banknotes under any circumstances, as they are most probably stolen.

Some photos of IBNS ink-stained banknotes:

Glued banknotes

Some IBNS are based on the use of strong and permanent glue that bond the banknotes into a solid block. Removing single notes is not possible without being torn into small pieces, which prevents their further use as a means of payment.

Photo of banknotes glued together (IBNS):

Frequently asked questions

Are all stained banknotes stolen?

No. If there are small stains on a banknote but not on the edge of the note, and if the edges of the banknote are undamaged, then it is most probable that the stains are not from an activated IBNS.

Examples of stained banknotes that are not the result of IBNS activation:

What should I do if someone offers me ink-stained or bleached banknotes?

Refuse to accept the banknote and request other ones. The lawful owner of stained or bleached banknotes must themselves bring them to Banka Slovenije to change them. The staining on banknotes can indicate that they were involved in a crime where an IBNS was activated. Refuse also bleached banknotes, since this can indicate an attempt to remove the IBNS ink-stains caused by activation of the IBNS.

What should I do if I have received ink-stained banknotes?

Bring the banknotes to Banka Slovenije and explain how you obtained them. Banka Slovenije will check if the banknotes were stained using an IBNS.

  • If it turns out that the banknotes were stained by activation of an IBNS, you will not be entitled to exchange them. Banka Slovenije only exchanges such banknotes at the request of the original owner who has been the victim of a crime that caused the banknotes to be stained by an IBNS. In the event of suspicion of a crime, the competent authorities (police) will be involved in further investigations.
  • If it turns out that the stains were not caused by activation of an IBNS, you will be entitled to exchange them.

What should I do if someone offers me glued banknotes?

Hand the banknotes back and request other ones. The lawful owner of glued banknotes must themselves bring them to Banka Slovenije to change them. Such banknotes were most probably glued together on activation of an IBNS during an attempted robbery or theft.