Tan Chi Min, who is suing RBS for wrongful dismissal, alleges that the bank's minutes of his disciplinary meeting held in September last year did not accurately reflect what was discussed and omitted details of conversations about how traders at the bank tried to influence RBS's interbank lending rate submissions.
More than a dozen banks are currently under investigation by regulators in the United States, Europe and Asia for suspected rigging of the London interbank offered rate (Libor), which is used to price trillions of dollars worth of financial products.
RBS confirmed earlier this month in its half-year results that it was among those banks being investigated. Last month rival lender Barclays Plc was fined $453 million in July by U.S. and UK regulators after its staff reported false interbank rates.
Tan was sacked from his Singapore-based role as head of delta trading for the bank's Global Banking & Markets division in November 2011 for trying to improperly influence the bank's rate setters. Delta trading involves using derivatives to mirror the price moves in a basket of securities.
In papers dated Aug. 10, Tan says the information omitted from the minutes includes reference to a conversation from March 2008 about the submission of Libor rates. Tan claimed that a trader for the bank, Will Hall, changed the Libor submission himself even though he was part of the Japanese yen swap desk in London.
The papers say Tan then raised the issue at his disciplinary meeting, saying that the bank's internal procedure in London seemed to be that "anyone can change Libor".
He also claims the meeting referred to a Bloomberg messenger conversation on March 14, 2011, during which Paul White, who was a rate setter for the bank, informed trader Robert Brennan that he wanted Libor to be fixed high. Brennan then mentioned this to traders on a subsequent conference call, according to the documents.
White declined to comment when contacted by Reuters on Thursday. Reuters could not locate the other traders.
Tan filed his lawsuit against the bank late last year, claiming the practice of traders making requests to the bank's rate setters was well known by RBS management. These latest filings come in response to requests from RBS that he provide specific examples of when this alleged input occurred.
RBS is disputing the allegations, saying Tan was dismissed for gross misconduct and that it followed its company disciplinary policy in deciding to terminate his contract. It has already announced that it has dismissed several employees in r elation to its inquiries into its interbank rate setting.
"We confirm, per our disclosures during our interim results on 3rd August, that we have dismissed a number of employees for misconduct as a result of our investigations into the setting of LIBOR and other interest rates," said a spokeswoman for RBS in Singapore.
"RBS Group continues to co-operate fully with ongoing investigations relating to the setting of LIBOR and other interest rates."
Tan is claiming a loss of bonuses from the bank comprising S$264,522 ($211,300), 71,563,061 yen ($903,000) and 3.3 million RBS shares.
Thomson Reuters Corp is the British Bankers' Association's official agent for the daily calculation and publishing of Libor.
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