Professional investors have slammed an “embarrassing” technical glitch for the ASX, which saw price-sensitive announcements unable to be published for several hours this morning, resulting in about 50 companies being placed in trading halts for much of the day.

The ASX apologised for the disruption to trading, and said on its website that: “All company announcements post 11:22am AEDT have been published. ASX is working with listed companies to publish impacted announcements submitted before 11:22am AEDT.”

Grocery and hardware wholesaler Metcash was one of the companies put in a trading halt, ultimately falling 9.2 per cent when its shares resumed trade in the afternoon, following a poorly received interim result.

Professional investors like Wilson Asset Management lead portfolio manager Matthew Haupt said the outage was frustrating.

“We were there waiting, especially with companies like Metcash coming out with their results, obviously a big day for them and unfortunately unable to trade, and it happened to quite a few holdings today,” he told The Business.

However, he said it was unlikely to have caused losses for most investors.

“If it was material information, they’ve been in a trading halt,” he observed.

“But, obviously, you want to trade on all the available information. So not having information out is incredibly frustrating.

“So it is a big deal, but as far as materiality goes, unlikely to be big misses there, but it’s just more of a nuisance than anything else.”

It was more than a nuisance for the ASX, which itself finished down 2.8 per cent to $56.58, hovering just above what would be its lowest levels in seven-and-a-half years.

Australia’s major stock exchange has been plagued by a raft of technical problems, with the greatest being a settlement platform, CHESS, that is many decades old and long overdue for replacement.

Its previous proposed successor, based on blockchain technology, was beset with problems, delayed by years and ultimately shelved, taking the ASX back to the drawing board.

The exchange is also now under intense scrutiny from its main regulators, ASIC and the Reserve Bank, who are becoming increasingly worried about its aging, and at times failing, technology.

ASX closes lower as AUB shares dive

Overall, the benchmark ASX 200 index completed its day-long trudge downhill to close the session 0.6 per cent lower at 8,565 points.

Energy, buoyed by higher oil prices, basic materials and utilities were the only sectors to make any headway, while health care was dragged down by selling in the sector’s heavyweight CSL (-1.4 per cent) along with a steep fall for Resmed (-4.6 per cent).

The big loser was insurance broker AUB, crashing 17.8 per cent after a private equity consortium bailed out on a takeover bid.

Treasury Wine Estates fell moderately after announcing a big impairment charge against its US business, but its share price is already at its lowest levels since 2018.