Noble shares take second-day drubbing

Noble Group's shares faced a second wave of selling despite analysts' skeptical view of an anonymously written critical research report comparing the company to Enron and assigning a 10 Singapore cent price target. 

"Neither of those was really supported in the document," Conrad Werner, head of research at Macquarie, told CNBC. 

Iceberg Research published a report headlined "Noble Group, a repeat of Enron," and saying more critical reports are on the way. The report alleges that the Singapore-listed commodities trader's accounting treatments were "unusual," result in "fabricated" profit and "intentionally misleads credit agencies and investors."

In a statement to the Singapore Stock Exchange Monday, Noble said it "completely" rejected" the allegations, adding that all the information cited in the report was in the public domain. After the market close, Noble issued an additional statement via SGX, disputing several of Iceberg's assertions and noting it had "a solid balance sheet and industry leading liquidity headroom." 

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That didn't support the share price, which closed down 5.4 percent at 1.05 Singapore dollars in mid-day Tuesday trade after dropping 7.9 percent Monday.

Interestingly, Iceberg agreed with Werner's assessment, saying in emailed comments Tuesday that its first report didn't support a comparison with Enron, but advised staying tuned for its second and third reports. 

Werner specifically criticized Iceberg's assessment of Noble's 13 percent stake in Australia-listed coal company Yancoal. Iceberg claims Noble is valuing its stake at 55 times the market value of its stake, but Werner noted this has largely been true since Yancoal was listed in 2012. 

Noble wrote down the value of the stake in 2013 and with coal prices remaining weak, another writedown may be on the cards this year, Werner noted. 

"But Iceberg are suggesting that the whole asset needs to be written down to zero, which we think is sensationalistic and an extreme conclusion," Werner told CNBC. 

Noble weighed in on the valuation question. "The carrying values of our associates, including Yancoal, are tested for impairment using discounted cash flow models that are updated every quarter," it said in Tuesday's filing with SGX, adding that the valuation is currently being audited for its upcoming results release.

In a report, Macquarie noted Noble uses a financial model to value the stake, a process reviewed by its auditors Ernst & Young, to compensate for the thin trading in Yancoal's shares. The stake is currently valued at $677 million on Noble's balance sheet, compared with a stock market value of $11 million, Macquarie said.

But Iceberg appears unwilling to accept the use of a financial model. "You cannot seriously explain a $600 million gap by saying shares are thinly traded," it said in an email that used the first-person "I," in a departure from Monday's use of "we." 

Macquarie, which is sticking with its Outperform rating and 1.60 Singapore dollar target price on the stock, isn't the only one questioning Iceberg's analysis of Noble. 

"The question really is, from a credit perspective, is the cash really there? And so far I don't think there have been any allegations that the cash isn't there," Joe Morrison, a senior analyst at Moody's Investors Service, told CNBC. "Mark-to-market isn't a cash flow item." 

There are few clues about the identity of Iceberg. Its website is a Wordpress blog, it has no archived reports and the "about" section claims only that Iceberg identifies earnings misrepresentations. Its Twitter account has sent only a handful of tweets. 

People often ask us: how do you make money? We don't now. But if our research is credible, it will be an asset later on for Iceberg.

Iceberg's motivations are somewhat mysterious. It claims it has no positions in Noble's stock and is acting only as a whistleblower.  

"You should assume that Iceberg Research has and/or will file as a whistleblower with regulators," the report said. SGX said it wasn't aware of a "registry" for whistleblowers in Singapore.

Noble also questioned Iceberg's motives. "If their intention, as claimed in the report, was to highlight supposed deficiencies in our accounting principles for the benefit of investors, it would have been normal to approach the group to discuss their concerns, rather than publishing a report of this kind shortly before our annual results announcement and just before a holiday period," the company said in its filing Tuesday.

But the validity of Iceberg's allegations may be irrelevant for the stock price. 

"The near-term uncertainty is likely to linger, if the previous Olam-Muddy Waters episode is anything to go by," Carey Wong, an analyst at OCBC, said in a note Tuesday, putting its Buy call and 1.30 Singapore dollar fair value under review. 

Wong noted that the "blackout" period before Noble releases its full-year results on Feb. 26 may prevent the company from pro-actively meeting with investors. 

Iceberg said Tuesday that it published the report at this time because it was ready, adding it didn't believe the quiet period impacted Noble's ability to respond. 

In 2012, Carson Block – the short-seller who founded research firm Muddy Waters – issued an attack on Olam, alleging accounting irregularities and criticizing the company's high debt levels. Olam denied the allegations in a long rebuttal, but its stock dropped sharply and it still hasn't fully recovered.

—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1