Former JP Morgan Chase trader Javier Martin Artajo was arrested in Spain today. The arrest came. Javier Martin Artajo was the supervisor of Bruno Iksil, who executed to trading losses know as the "London Whale" in which $6.2 billion was lost. Martin Artajo and a low level trader, Julien Grout, were charged with wire fraud and conspiracy to falsify books and records related to the trading losses. l.