The brokers who have been acquitted are Colin Goodman and Danny Wilkinson, who both used to work at ICAP, Noel Cryan, formerly from Tullett Prebon, and Terry Farr and James Gilmour, both formerly of RP Martin.
The verdict for the sixth broker, Darrell Read, who used to work for ICAP, is still being considered. The jury has acquitted Read on one count of conspiracy to defraud but is considering another count.
The jury initially retired to consider its verdict on Tuesday morning.
The brokers were brought to trial as a result of an investigation by the Serious Fraud Office (SFO), which alleged that they had conspired with Tom Hayes to skew Libor.
"The key issue in this trial was whether these defendants were party to a dishonest agreement with Tom Hayes," said David Green, director of the SFO. "By their verdicts the jury have said that they could not be sure that this was the case. Nobody could sensibly suggest that these charges should not have been brought and considered by a jury."
A statement from law firm Bark & Co said that Cryan, their client, was "delighted" with the verdict, and continued: "Mr Cryan is relieved finally to be able to put this matter behind him, and looks forward to being able to get on with his life after two years with this hanging over his head."
Hayes, who used to work for UBS and Citigroup, was convicted in August of last year. His prison sentence was later reduced from 14 years to 11 years on appeal.
The case of the brokers was heard at London's Southwark Crown Court by Mr Justice Hamblen, and the trial formally started more than four months ago, in October of last year.