The question of the existence of the mysterious Onecoin blockchain was advanced this week by two IT expert witnesses, clearing the air in what may be the biggest crypto fraud case of all time.

Ruja Ignatova, the founder of the supposed cryptocurrency Onecoin, allegedly collected more than $4 billion from investors between 2014 and 2017. Critics call Onecoin a pyramid scheme that uses a form of direct sales to persuade customers to become distributors themselves and recruit more customers.

Prosecutors are convinced that several million euros originating from Onecoin sales were moved to Germany. A Munich lawyer and a couple from Greven now have to defend themselves in court against the accusation of having helped in the billion euro fraud.

The question of whether Onecoin is actually a cryptocurrency and whether a real blockchain ever existed is central during the trial.