Last month the French bank hit back at the defections by filing a $750 million lawsuit citing damage to its CDO business. But Mizuho wasted no time in firing off a sharp riposte. It read: "Calyon’s former employees left Calyon for Mizuho of their own volition. They were not recruited by Mizuho directly or through a search firm. None of the former Calyon employees had employment, non-compete or non-solicitation agreements with Calyon. Calyon’s allegations of damage to its CDO business caused by the individuals’ resignations and their alleged misappropriation of significant, proprietary intellectual property are unsupported by the facts and are inconsistent with Calyon’s own public statements about the continued success of its fixed income group."
Mizuho says it has investigated Calyon’s allegations appropriately and says the litigation is without merit.