Singapore's central bank and stock market operator are conducting an extensive review of recent share price volatility in three inter-linked Singapore companies, which wiped out billions of dollars in combined market value from the firms.
Singapore Exchange Ltd, which is both the market operator and the regulator, suspended trading in shares of Blumont Group Ltd, Asiasons Capital Ltd and LionGold Corp Ltd on Oct. 4, after sharp declines in their stock prices.
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It then slapped trading restrictions on them for two weeks.
"MAS and SGX are conducting an extensive review of the activities around these stocks," the Monetary Authority of Singapore (MAS) told Reuters late on Thursday in an e-mail response to questions.
"We cannot divulge more information at this point so as not to undermine potential investigations. This episode has also surfaced broader issues regarding the market structure and practices which MAS and SGX intend to review thoroughly. Upon completion of the review, we will consult the public if changes are required," it said.
The comments from the MAS, which oversees the SGX, follow criticism in the local media that SGX had stepped in too late to tame the volatility.
SGX's dual role as market operator and regulator has in the past raised questions about a conflict of interest as it regulates listed companies that are also its clients.
The remarks from Singapore's central bank are also the first confirmation that authorities had kicked off an investigation into the activities surrounding the three stocks.
The stocks lost up to S$8.7 billion ($7 billion) in combined market value in a few sessions this month, and fell back to being the penny stocks they were before dramatic gains earlier this year.
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Blumont's stock closed at S$0.20 on Thursday, compared with a high on Oct. 1 of S$2.50. Asiasons Capital fell 2 percent to S$0.23 at Thursday's close, against a high of S$2.80 at the beginning of the month.
Under the trading curbs, the first to be imposed on any Singapore-listed stocks for five years, SGX declared the stocks as "designated securities." That meant traders could not short-sell them and had to pay for any purchases with cash upfront.
Traders have said several brokerages in Singapore could lose millions of dollars following those big price falls.
The MAS however said the operations and financial positions of broking firms exposed to those stocks remain sound and it will continue to keep a close watch on the brokerages.
"MAS has been closely monitoring the exposure of the broking firms by collecting reports on losses and major counterparty exposure arising from their exposures to the three counters."
Earlier on Thursday, an association representing Singapore's retail investors called for a probe into the three stocks.
Analysts had said sharp gains seen in the three stocks earlier this year had not been backed by obvious business fundamentals.