The Tokyo Stock Exchange plans to resume normal operations Friday after it halted trading for the entire day Thursday owing to what it said was a malfunction in its computer systems — the worst such outage ever.
There was no indication that the outage at the world’s third-largest exchange resulted from hacking or other cybersecurity breaches.
“We are extremely sorry for the troubles we have caused,” Koichiro Miyahara, president and CEO of the exchange, told reporters late Thursday.
The exchange issued a statement later saying it would open as usual Friday. It said it foresaw no problems with resuming trading.
Miyahara and other exchange officials said a computer hardware device they called “Machine 1” failed, and the backup, “Machine 2,” didn’t kick in, so stock price information was not being relayed properly.
The officials characterized the problem as a memory malfunction.
They said that rebooting the system during a trading session would have caused confusion for investors and other market participants.
Perplexed passers-by studied quote-less electronic screens in Tokyo’s financial district, and newspapers’ evening editions carried listed companies’ names but blank prices.
Brokerages fielded a flood of calls from frustrated investors.
“There should be a Plan B,” Norihiro Fujito, chief investment strategist at Mitsubishi UFJ Morgan Stanley Securities, told broadcaster NHK.
The Tokyo exchange is the world’s third-largest bourse after the New York Stock Exchange and Nasdaq, with a market capitalization of nearly $6 trillion.
Foreigners account for about 70% of all brokerage trading in the Tokyo exchange, both in terms of value and volume, so news of the outage left investors both in Japan and overseas wondering what happened.
The malfunction of basic hardware drew attention to vulnerabilities in the country’s digital systems. Newly appointed Prime Minister Yoshihide Suga has made upgrading such infrastructure a priority, viewing it as