The Hong Kong Monetary Authority says UBS traders tried to manipulate the city’s benchmark interest rate between 2006 and 2009, Bloomberg reports.

Read: More traders suspended in currency probe

The authority says around 100 internal chat messages between UBS employees show traders requesting that the bank alter its data for the Hong Kong Interbank Offered Rate, says Bloomberg.

The tinkering had a negligible impact on rates, the authority says, and UBS doesn’t face any fines. But, the authority did ask that UBS discipline the traders.

Read more here.

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