The BOJ is also giving out more information on its bond purchases than it used to, in order to give investors advance notice of its large orders.

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The central bank is also giving out more information on its bond purchases than it used to, in order to give investors advance notice of its large orders.

WSJ: Rising Japan Bond Yields Underscore BOJ's Challenge

They soon noticed a quirk in the Nasdaq software: If they were to place a SOES bid that said "I'll buy at the offer or up to 20% over it, " their order would automatically take precedence over all other market orders and would give them an advantage in a rising market.

FORBES: Guerrillas on Wall Street