Noble has suffered repeated blows over the past year. Already hit by the global slump in commodities prices, the traders' stock has tanked sinc February 2015, when Iceberg Research published a report alleging that Noble's accounting treatments were creating "fabricated" profits.
Despite Noble's vociferous denials - it alleges Iceberg is run by a disgruntled former employee - and the implementation of a program of asset sales to bolster its balance sheet, the company was cut to junk status in January by ratings agencies Moody's and Standard & Poor's.
In February the company reported its first annual loss since 1998, on the back of a $1.2 billion writedown on weak coal prices.
On May 17 Fitch Ratings became the last of the big ratings houses to remove Noble's investment grade rating, saying that the company's debt maturity profile was weakening. It gave the trader a "stable" outlook.
Noble's shares closed down almost 75 percent on Friday from their level in the days before Iceberg's report was published, then lost more than 3 percent to trade at 30 Singapore cents each early on on Monday after Alireza's exit was made public.
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