The judge has not yet said what the family should be paid in compensation.

A wealthy Kuwaiti family has won a lawsuit against Credit Suisse over the loss of $29 million invested with the Swiss banking giant during the 2008 financial tsunami. 

Mahmoud Haji Haider Abdullah and his sons, Maytham, Mahdi and Mansour, had lost the sum at the end of October 2008, Judge Andrew Baker said earlier this week. He did not rule how much money they can recover, however. Court filings allegedly state the family is worth at least $500 million. They were clients of Credit Suisse’s London-based private banking unit. 

Baker said Credit Suisse was responsible for “actionable breaches of duty” over the family’s purchase of a $20 million three-year note in May 2008. In October that year, Maytham and Mahdi chose not to meet a margin call issued by the bank, and subsequently suffered “a total loss of their net investment” in a series of notes and were left overdrawn at Credit Suisse by $336,275.60. 

The bank had argued that the family’s refusal to meet the margin call “was so unreasonable as to amount to a failure to mitigate loss”, and that the losses “resulted from the extreme nature and severity of the 2008 crash”, the judgment says. But Baker said “it was not unreasonable to prefer to exit their investments and stop their losses as they did”.

WealthBriefing has contacted Credit Suisse for comment on the matter and will update coverage accordingly. 

The story originally appeared in Bloomberg. 

Baker did not determine what Credit Suisse should pay the family as further calculations would be required before setting a figure in stone.