Two major financial players are now suing the London Metal Exchange for a total of nearly half a billion dollars, after the exchange earlier this year suspended nickel trading and cancelled some trades following wild swings in the metal’s price.

The activist hedge-fund manager Elliott Management is seeking more than $456m, and has now been joined by market-maker Jane Street, which is claiming about $15.3m, according to Hong Kong Exchanges & Clearing, which owns LME.