Euronext apologises for the inconvenience caused by the trading interruption and closing process issue on Euronext’s cash and derivatives markets (except Oslo Børs) on Monday 19 October 2020. The root cause was a technical issue affecting a third-party middleware system. Actions have been taken to ensure that a similar issue does not happen again. Euronext was in a position to secure a smooth market opening on 20 October 2020. The official closing prices of 19 October 2020 are available here.
As a reminder, on Monday 19 October 2020, due to a technical issue impacting all Euronext cash and derivatives segments, trading was halted at 9.48 CEST on all Euronext segments.
The root cause of the technical issue which triggered the market halt was identified and resolved. It was a technical issue affecting a third-party middleware system in charge of managing the persistence of data, and was not related to a cyber-attack. The initial issue impacted the closing process: trading continued during the pre-auction process, after 17.30 CEST, creating, in some cases, a sudden share price movement, due to orders that should not have been executed during this phase, and inaccuracy of some closing prices. As these issues were considered as improper trading conditions, Euronext had to cancel all trades performed after 17.30 CEST, except for commodities, and reset order books for all Euronext instruments.
Euronext’s trading rules required updating the closing price to the last executed price. All market participants and data vendors were asked to realign on the corrected levels; however, 19 October 2020 prices across providers may not all be updated yet.
The correct closing prices of 19 October 2020 for the main indices are as follows:
- PSI20: 4,214.10
- AEX: 567.52
- ISEQ20: 1,162.82
- CAC40: 4,942.62
- BEL20: 3,262.38