For real?

"The notable connoisseur and onetime director of the Metropolitan Museum of Art Thomas Hoving famously claimed in 1996 that approximately 40 percent of all art in museums is either a fake or a forgery. More recently, Yann Walther, the chief of Switzerland's Fine Art Expert Institute claimed that estimates of 50 percent of art on the market being forged or misattributed are likely conservative. Whether or not theses figures are accurate, there clearly exists in the art world a problem with fraud."

Amore, A. (2015). The Art of the Con. New York, NY: Palgrave Macmillan Trade. p.9