Drawing heavily on the case brought by New York's attorney general last April, they also accused the defendants of manipulating the market by printing unbacked tethers.

Bitfinex denied the accusations, describing the case as "mercenary and baseless," stating it would contest any "nuisance settlements".

In November, Tether published a letter of intent to file a motion to dismiss another separate class action that seeks retribution for manipulating the bitcoin price, claiming damages of more than $1 trillion.

The letter, released more than a month after the Lawsuit was originally filed , claimed plaintiffs were unable to prove Tether or Bitfinex's involvement.

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