DEFINITION of 'Mr. Copper'
Otherwise known as Yasuo Hamanaka, Mr. Copper was a trader in the copper market who lost over $2.5 Billion for his employer, Sumitomo Corp. (in Japan). The losses amassed from unauthorized trading in secret accounts between 1985 and 1996.
BREAKING DOWN 'Mr. Copper'
He was also referred to as "Mr. 5%" because at one point he controlled 5% of the world copper market. Hamanaka's scandalous activities represent the greatest unauthorized trading loss in history.