Nine people appeared in court over their alleged involvement in an £81 million fraud operation on the Royal Mail.
Eight of the defendants connected to four logistics companies are accused of abusing a self-declaration system for large postage firms by only declaring approximately a quarter of the mail actually sent through the post.
The defendants are from Slough, Buckinghamshire, Oxfordshire and London.
The court heard that it went on over a period of nine years, between May 2008 and May 2017.
The alleged under-declaration allowed the companies to make illegal profits and pass on some savings to customers in order to gain an advantageous market share.
The four companies involved in the alleged fraud are Packpost International Ltd; Global Express Worldwide Ltd; Tiger International Logistics Ltd and Worldwide Transport Express Ltd.
The companies have been charged with conspiring together to commit fraud by false representation against postal operators intending to cause a loss to Royal Mail and other postal operators or to expose them to loss.
The case was sent to Southwark Crown Court in January where a provisional date of May 2022 was set for a 12 week trial.
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