SINGAPORE (Feb 24): Another damning report from secretive stock research firm Iceberg Research sent shares of commodity trader Noble Group plunging on Friday, triggering an unusual trading activity query from the Singapore Exchange.

At the close on Friday, Noble shares were down 16.7% or 4.5 cents to 22.5 cents with 623.4 million units traded, making it the most active stock of the session.

Noble's slide prompted a trading query from SGX at 3.20pm. In a response at 3.46pm, Noble said that apart from the Iceberg report, it was not aware of any undisclosed matter that could have accounted for the trading activity.

It was also unaware of any information not previously announced that triggered the surge in volume of its shares traded.

In its latest report, Iceberg questioned the surge in Noble's share price following the Sinochem speculation. Iceberg argued that Noble has been struggling to find a good strategic investor because of doubts over the value of its commodity contracts.

Noble has also been forced to sell some of its businesses to obtain capital because its contracts could not be sold, and has not made the management changes required to improve the situation, Iceberg alleged.

Since Iceberg's first report questioning the value of Noble's assets, the company has seen its share price fall 81%, lost its investment-grade credit rating and had to swallow more than US$1 billion of impairments.

In a note on the event, BNP Paribas analyst Sneha Kohli says she did not find any new information in Iceberg’s report.

“The concerns they had on the contract valuation have been an old and recurring theme. Based on the information available to us, we think that Noble’s operations have been improving in 2016.”

However, Kohli added that the insufficient disclosure on the gains/losses on commodity/ derivative contracts have concerned BNP too and that the research house have provided feedback to Noble.