Two senior banking executives formerly of the firm Martin Brokers have been fined and banned by the Financial Conduct Authority (FCA) for compliance and cultural failings relating to Libor manipulation.
Martin Brokers former chief executive David Caplin was fined £210,000, while former compliance officer Jeremy Kraft was fined £105,000. Martin Brokers was also fined £630,000 in 2014 for the offence.
The pair have also been banned "from performing significant influence functions at financial services firms".
The regulator added that their conduct at the firm led to a culture where Libor manipulation became acceptable and they allowed it to continue undetected for some time.
Georgina Philippou, acting director of enforcement and market oversight at the FCA, said: "Mr Kraft and Mr Caplin were responsible for setting the right culture at Martins and ensuring that the firm's risk management systems and controls were adequate to oversee its broking activities. They failed to do this.
"Proper systems and controls were non-existent and there was a culture at Martins where revenue came first and compliance was seen as unimportant rather than as an integral part of the running of the firm.
"Both individuals also ignored obvious risks such as the risk that brokers would give or accept inducements. This risk did in fact crystalise when brokers at Martins were induced to assist in Libor manipulation in exchange for corrupt brokerage payments. Consequently, the integrity of the financial markets was compromised."
Caplin and Kraft received a 30% discount on their fine as a result of settling with the regulator early.