Ruja Ignatova (Bulgarian: Ружа Игнатова) (born 30 May 1980) is a Bulgarian-German convicted fraudster. She is best known as the founder of a Ponzi scheme known as OneCoin, which The Times has described as "one of the biggest scams in history".[3][4][5] She was the subject of the 2019 BBC podcast series The Missing Cryptoqueen.[6]