Hedge fund customer took them to arbitration seeking $1-3M in damages for their auto-liquidation. At issue was closing transactions executed at prices away from the market, which when used to remark their book, increased the size of the call dramatically and resulted in even more liquidation.
http://www.reuters.com/article/2015...active-auto-liquidation-idUSL1N0VS1PH20150218
http://www.reuters.com/article/2015...active-auto-liquidation-idUSL1N0VS1PH20150218
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