Two international conwomen – Evelyn Burton and Lyla Andre – were warned that they face going to jail after their case was heard at London’s Wood Green Crown Court.
Among those cheated by the “ruthless” pair was the actress Susan George, who is still waiting for prize-money from one horse show.
They also promised show jumper Nick Skelton that they would sponsor him for £1million a year for five years.
Another rider who became a target was Lisa Murphy, who was conned when Burton promised to buy her a horse for £70,000 and lease him back to her and pay her £3,000 a month.
In 1997 Burton also promised to sponsor some of the shows for the Arab Horse Society and promised substantial prize money.
Probably their biggest coup was meeting the Queen and Duke of Edinburgh in May 1997 after handing over a sponsorship cheque for the Royal Windsor Horse Show, which subsequently bounced.