The exchange had 2,549 listed companies at the end of February with a combined market capitalisation of HK$52.9 trillion (US$6.8 trillion).

While there is probably no sinister reason involved, it may be interpreted as a way to pre-empt any negative investor reaction. Investors are wary of sudden stock suspension. It rekindles memories of the misuse of trading rules during China’s last stock market crash in 2015.

Then, more than 1,000 companies, or about half of the publicly traded companies on the Shanghai and Shenzhen exchanges, requested trading halts in a bid to avert a sell-off.

That eventually prompted complaints from overseas investors. Global index compiler MSCI warned in early 2016 about the misuse of suspension rules as one of the conditions for adding China’s yuan-denominated shares into its emerging market indices.

The suspension also clouded a strong market start to the second quarter, as the Hang Seng Index jumped more than 1 per cent in a holiday-shortened week. The market will close for three trading days from April 2 to 6 for Easter. 

The massive suspension also put to test the rebound in Asia’s third-largest capital market, which had been roiled by rising US bond yields and the fallout from the implosion of Archegos Capital Management.

Many of the companies have applied for a trading halt for failing to disclose their preliminary unaudited results by the March 31 deadline.

“The auditor is still auditing the information provided by the company so as to clarify the management accounts, thus to complete the audit procedures,” said Hainan Meilan in an exchange statement. China Huarong and GCL-Poly said their auditors would need more time to review the accounts.

The shares of the three companies fell at least 1.2 per cent on Wednesday.