(FT.com) Five broker-dealers accused of conspiring with Tom Hayes to manipulate the Libor benchmark have been found not guilty in a London court, in a major setback for the UK’s Serious Fraud Office.

The brokers – Danny Wilkinson and Colin Goodman from ICAP, Noel Cryan from Tullett Prebon and RP Martin’s Jim Gilmour and Terry Farr – stood trial at London’s Southwark Crown Court for about 15 weeks in the SFO’s prosecution over alleged efforts at Libor manipulation. The jury is still considering one count against Darrell Read from ICAP.

Mr Hayes was found guilty of rigging Libor last August, and sentenced to 14 years in prison, though that sentence was later reduced.

Prosecutors alleged the men acted as go-betweens by passing along requests between traders for what number the rate should be set at on a given day. The SFO also alleged that Mr Goodman, in his daily emails, would suggest where he thought Libor would be set that day, and would alter the figure to appease Mr Hayes’s requests.

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The prosecution also alleged that the brokers, with nicknames such as “Big Nose,” “Lord Libor” and “Sarge,” were rewarded by Mr Hayes, one of their biggest clients because of the volume of trading he conducted, with extra commission for their help.