Dutch lender Rabobank, which sponsors rugby's RaboDirect Pro 12, has been fined €774m (£663m) by UK and overseas regulators as it became the fifth group to reach a settlement over the Libor rate-rigging scandal.
The group's penalty includes a £105m fine imposed by Britain's Financial Conduct Authority (FCA) for "serious, prolonged and widespread misconduct" relating to interbank lending rates, while it has also agreed penalties with regulators in the Netherlands, United States and Japan.
Rabobank chairman Piet Moerland quit immediately and apologised for the "inappropriate conduct" of around 30 employees found to be involved in attempting to fix the interbank lending rates.
He said he was "shocked" by their behaviour and added the bank also failed to "sufficiently appreciate" the risks of Libor and Euribor submitting processes.
The FCA's fine is the third biggest imposed by the regulator and its second highest for Libor manipulation.
It found more than 500 attempts within Rabobank to manipulate Libor, with the group's London office significantly involved in the scandal, alongside offices in Utrecht, the US, Japan, Singapore and Hong Kong.
Rabobank employs up to 200 front office staff in London, including its money market traders.
The FCA said Rabobank's misconduct was "among the most serious" uncovered so far by the regulator in relation to Libor.
It found emails and communication revealing hundreds of requests to manipulate the rate, which governs the price of hundreds of trillions of pounds of loans and transactions around the world, including mortgages.
In one example, a Rabobank manager said to another trader who had made requests to Libor submitters that he was "fast turning into (that trader's) bitch!!!!".
Another Libor submitter said to a trader that he'd "never change libors without consulting you", adding "we are on the same team".
Rabobank's fine comes just a month after City broker ICAP was hit with a £54m penalty by American and UK regulators, following a £290m fine for Barclays, £940m for Swiss bank UBS, and £391m for the Royal Bank of Scotland.