TORONTO — The chief executive of Manulife Financial Corp. says the insurer is "highly confident" it will prevail in its legal battle with hedge fund Mosten Investment LP over insurance contracts. Roy Gori told a conference call discussing its latest quarterly results today that he's not sure when a decision will be rendered in the case brought against Manulife's life insurance subsidiary, but the company is "prepared to see this through." The trial involving one of Manulife's insurance contracts purchased by Mosten wrapped up last year.