Three former traders at ICAP, the world's largest inter-dealer broker, have appeared in a London court charged with running a four-year scheme to manipulate Libor benchmark interest rates.
The men, who spoke only to confirm personal details such as addresses, bring to nine the number of people facing criminal charges in Britain over allegations they rigged the London Interbank Offered Rate (Libor), which is used to price about $450tn of products from complex derivatives to home loans.
The hearing at Westminster Magistrates' Court on Tuesday is the latest in an investigation that stretches from North America to Asia, shaking public faith in the financial industry.
The scandal has so far led to fines of $6bn imposed on 10 banks and ICAP, according to the Reuters news agency.
Traders are alleged to have fixed Libor, which is based on a survey of what banks would charge each other for loans, by submitting answers that could nudge the reported rates by amounts that were tiny, but translated into big profits.
Former ICAP derivatives broker Darrell Paul Read, 49, his supervisor Daniel Martin Wilkinson, 47, and 52-year-old Colin John Goodman, a cash broker, are all charged with conspiracy to defraud between August 2006 and September 2010.
Britain's Serious Fraud Office (SFO), which brought the charges last month, alleges the three men conspired with Tom Hayes, a former yen derivatives trader who has already been charged with eight counts of conspiracy to defraud and is due to stand trial in January 2015, while he was working at UBS in Tokyo between 2006 and 2009.
They dishonestly agreed to procure or make submissions of yen Libor rates that were false or misleading and were intended to benefit Hayes' trading, the SFO said in documents outlining the charges.
Goodman and Read continued to work with Hayes in the scheme when the trader moved to Citigroup in 2010, the documents say.
The trio, who like Hayes have also been charged by US prosecutors, did not indicate any plea and have been granted conditional bail.
They will next appear at the higher Southwark Crown Court on April 30 for a case management hearing.