Ink-stained banknotes
Banknotes stained by Intelligent Banknote Neutralisation Systems
Intelligent Banknote Neutralisation Systems (IBNS) are used to secure the transportation and distribution of cash. In case of an attempted robbery or theft, the system is activated and the banknotes are rendered useless or neutralised.
Different neutralisation technologies are available in the market. The system that is most often used stains the banknotes with an ink and generates the so-called 'ink-stained banknotes'.
The use of intelligent banknote neutralisation systems is a preventive measure designed to ensure that criminals do not profit from their crime after stealing cash from an ATM or from a valuables transport box. This decreases the risk of retailers, banks and other professional cash handlers becoming victims of criminal actions.


How to recognise an IBNS ink-stained banknote
When a banknote is stained by an IBNS, the security ink used by the system soaks into the banknote paper and is generally more pronounced at the edges. Usually, the ink flows from the edges to the centre of the banknote, making a distinctive pattern.
The most common colours for security inks used by IBNSs are violet, green, blue, red or black.
Sometimes, criminals try to wash the stained banknotes and this creates variations in the original colour of the security ink due to the chemical reactions between it and the reagents used to wash the banknotes. This procedure may also alter the original colours of the banknote and damage or eliminate some of its security features.
Below are some photographs illustrating banknotes stained by IBNSs, some of which have been washed.






IBNSs that render banknotes useless using glue
To prevent stolen banknotes being used, some intelligent banknote neutralisation systems use glue to permanently and irreversibly bond all the banknotes together into a solid brick.
It is impossible to peel off individual banknotes without tearing them to small pieces.


Legislation
The Decision of the ECB of 19 April 2013 on the denominations, specifications, reproduction, exchange and withdrawal of euro banknotes, sets forth in Article 3 (2) that banknotes damaged by intelligent banknote neutralisation systems will only be exchanged when the applicant is the victim of the criminal activity leading to the damage to the banknotes. Under the terms of this Decision, where a national central bank knows or has sufficient reason to believe that the banknotes have been intentionally damaged, it should refuse to exchange and should withhold the banknotes, in order to avoid the return of such euro banknotes into circulation or to prevent the applicant from presenting them to another central bank for exchange.
In Portugal, the installation of new neutralisation systems and the introduction of changes to systems being used must be previously tested by Banco de Portugal. These tests focus on how these systems operate and on their results.
The use of IBNSs is regulated by Instruction of Banco de Portugal No 1/2011, as amended by Instruction of Banco de Portugal No 37/2012 and by Circular Letter No 66/2019/DET.
IBNS Frequently Asked Questions
What is an Intelligent Banknote Neutralisation System – IBNS?
Intelligent banknote neutralisation systems are security mechanisms installed in ATMs or in valuables transport boxes that stain or partly damage banknotes following an attempted theft or robbery.
The IBNS's goal is to remove the reward of the theft, making it harder or even impossible to use the banknotes as a means of payment, and to increase the probability of catching the criminal.
These systems render banknotes useless by staining them with ink or by other means, such as glue.
During an attempt to steal cash from an ATM or valuables transport box protected by a neutralisation system using security ink, the banknotes are extensively and permanently stained.
During an attempt to steal cash from an ATM or valuables transport box protected by a neutralisation system using glue, the banknotes are permanently and irreversibly fused into a solid brick. If one tries to peel off single banknotes, they will tear to small pieces.
What should I do if someone offers me an ink-stained or discoloured euro banknote?
A stained banknote is quite probably a stolen banknote. Do not accept it and ask for another banknote.
The ink stains on the banknote may have been made by an intelligent banknote neutralisation system. Intelligent banknote neutralisation systems are security mechanisms installed in ATMs or in valuables transport boxes that stain or partly damage banknotes following an attempted theft or robbery.
Sometimes, criminals try to remove the security ink staining by washing or bleaching. This is why you should refuse to accept discoloured banknotes.
What is the risk if I accept a clearly ink-stained banknote?
A banknote stained by an intelligent banknote neutralisation system has quite probably been stolen. Therefore, you should not accept stained banknotes.
If you try to exchange the banknote stained by an intelligent banknote neutralisation system at any agency of Banco de Portugal or at another Eurosystem national central bank, the banknote will be withheld and you will be required to fill in a form. The competent authorities (police) will be involved in the investigation.
In principle, a banknote stained by an intelligent banknote neutralisation system will not be exchanged.
Banknotes damaged by IBNSs will be exchanged only at the request of the owner or otherwise authorised applicant who is the victim of the crime.
The exchange of damaged euro banknotes, including those damaged by intelligent banknote neutralisation systems, is governed by the rules set forth in the Decision of the European Central Bank of 19 April 2013.
What should I do if I find I have accepted a banknote stained by an intelligent banknote neutralisation system?
If you have accepted a banknote stained by an intelligent banknote neutralisation system you should take it to a branch of a credit institution or to Banco de Portugal or to any other Eurosystem central bank and provide information on the origin of that banknote.
Any credit institution that receives such a banknote will send it to the respective national central bank (in Portugal, Banco de Portugal). If necessary, the competent authorities (police) will carry out a criminal investigation.
What should I do if someone gives me an incomplete banknote or a set of glued banknotes?
This type of damage could also be due to the activation of an intelligent banknote neutralisation system following an attempted robbery or theft of an ATM or valuables transport box.
You should ask for another banknote that is not damaged.