OneCoin

thumb|OneCoin logo on the door of their office building in Sofia, Bulgaria, in 2016

OneCoin is a fraudulent cryptocurrency scheme conducted by offshore companies OneCoin Ltd (based in Bulgaria and registered in Dubai) and OneLife Network Ltd (registered in Belize), both founded by Ruja Ignatova in concert with Sebastian Greenwood. OneCoin is considered a Ponzi scheme due to its organisational structure of paying early investors using money obtained from newer ones. It was also a pyramid scheme due to the recruiting of investors without providing any actual product. The company maintained its own database of coins rather than using a blockchain and had no mining process which limited its ability to release and circulate coins. Many of the people central to OneCoin had been previously involved in similar schemes and business malpractice. OneCoin was described by The Times as "one of the biggest scams in history".