Traders Said to Rig Currency Rates to Profit Off Clients

Traders at some of the world’s biggest banks manipulated benchmark foreign-exchange rates used to set the value of trillions of dollars of investments, according to five dealers with knowledge of the practice.

Employees have been front-running client orders and rigging WM/Reuters rates by pushing through trades before and during the 60-second windows when the benchmarks are set, said the current and former traders, who requested anonymity because the practice is controversial. Dealers colluded with counterparts to boost chances of moving the rates, said two of the people, who worked in the industry for a total of more than 20 years.