By Amanda Cooper, Ankur Banerjee and Tom Westbrook
Global futures markets were disrupted for several hours on Friday after CME Group, the world’s largest exchange operator, suffered one of its longest outages in years, halting trading across stocks, bonds, commodities and currencies.
By 1335 GMT, trading in foreign exchange, stock and bond futures 
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CME blamed the outage on a cooling failure at data centres run by CyrusOne, which said its Chicago-area facility had affected services for customers including CME 
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The disruption stopped trading in major currency pairs on CME’s EBS platform, as well as benchmark futures for West Texas Intermediate crude 
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‘A BLACK EYE’
Trading volumes have been thinned out this week by the U.S. Thanksgiving holiday and with dealers looking to close positions for the end of the month, the outage posed a risk of spurring volatility, market participants said.
“It’s a black eye to the CME and probably an overdue reminder of the importance of market structure and how interconnected all these are,” Ben Laidler, head of equity strategy at Bradesco BBI, said.
“We complacently take for granted much of the timing is frankly not great. It’s month end, a lot of things get rebalanced.”
Still, the timing of Friday’s outage, during a shortened U.S. equity trading session with thinner volumes, helped limit its market impact.
“If there was to be a glitch day, today’s probably a good day to have it,” Joe Saluzzi, co-manager of trading at Themis Trading in Chatham, New Jersey, said.
Futures are a mainstay of financial markets and are used by dealers, speculators and businesses wishing to hedge or hold positions in a wide range of underlying assets. Without these and other instruments, brokers were left flying blind and many were reluctant to trade contracts with no live prices for hours on end.
“Beyond the immediate risk of traders being unable to close positions – and the potential costs that follow – the incident raises broader concerns about reliability,” said Axel Rudolph, senior technical analyst at trading platform IG.
A few European brokerages said earlier in the day they had been unable to offer trading in some products on certain futures contracts.
“My anticipation is that life goes on but everybody will have yet another look at their data centre arrangements and invest more in ensuring reliable supply because the importance of data center uptime is higher and higher,” Mikhail Zverev, Portfolio Manager at Amati Global Investors in London.
Regulators are tracking the situation, with both the Commodity Futures Trading Commission and Securities and Exchange Commission confirming they are aware of the issue and conducting ongoing surveillance.
BIGGEST EXCHANGE OPERATOR
CME is the biggest exchange operator by market value and says it offers the widest range of benchmark products, spanning rates, equities, metals, energy, cryptocurrencies and agriculture.
Average daily derivatives volume was 26.3 million contracts in October, CME said earlier this month.
The CME outage on Friday comes more than a decade after the operator had to shut electronic trade for some agricultural contracts in April 2014 due to technical problems, which at the time sent traders back onto the floor.
More recently in 2024 outages at LSEG and Switzerland’s exchange operator briefly interrupted markets.
CME’s own shares were up 0.4% in premarket trading.
