The Euronext Liffe London futures exchange suffered a four hour outage on Monday after monitoring systems for trades broke down.
The outage lasted from 7am until 11.15am, with many trades having to be cancelled by the exchange, after they slipped through the net when most trades were blocked following the outage.
This happened after the market opened automatically before the shutdown was fully completed by the exchange, as it sought to fix the trade monitoring outage.
Some trades on some markets carried on for a full 20 minutes before Liffe could complete the shutdown.
This was the first major outage since last December, when an outage lasted an hour, but there have been other minor outages since then.
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