The Australian Stock Exchange is investigating the cause of a system error that prevented a large number of stocks from being traded on Monday 19 September.
The error was caused by a hardware failure in the equities trading system’s main database, though the ASX is still investigating the root cause of the problem.
The market was unable to open at its scheduled time of 10am due to the error, with a staggered opening commencing at 11:30am announced instead, the ASX said.
The ASX explained that securities within the alphabetic range of A – M were then able to trade as expected, however those in the S – Z range experienced further delays due to an operational error, with market open pushed back until 12pm.
The market was incorrectly opened at 11:10am for securities in the N – R range, during which time a number of trades were made, however this group was then put back in to trading halt, with all trades made during the incorrect opening cancelled, and the new open delayed until 1:20pm.
The trading platform then experienced a further disruption at roughly 1:40pm, and 25 minutes later the entire market was halted, the ASX said, before announcing at 3:35pm that the market would not be reopening for the day.
“A full detailed incident report will be provided to Participants later this week.
“ASX will also schedule a customer forum next week to discuss the operational impacts, the communication process, and preventative actions,” the ASX said.
ASIC noted that market participants had a “legitimate expectation” that markets would perform to the highest standards, adding that it “will examine the cause and any effects of [Monday’s errors] as a priority and as part of our close oversight of market operators”.
“Historically, Australian trading platforms like ASX have at least met global benchmarks for up-times and reliability, with up-times on an annual basis regularly around 100 per cent,” the regulator said.
“We expect Australian market operators to continue to target this level of performance."