In 1967, the aristocratic Hungarian art collector Elmyr de Hory told his neighbor a secret. All the modern masters on the walls of his Ibiza mansion were fakes; he was the real painter. Others that he’d made, including artwork attributed to Henri Matisse and Pablo Picasso, had been sold to museums around the world. He’d lost his family fortune with the Second World War. Forgery was how de Hory made his living.

http://www.forbes.com/sites/jonathonkeats/2014/03/27/at-this-massachusetts-art-museum-some-forgeries-are-faker-than-others-but-better-not-trust-your-eyes/