It is the first legal claim to be filed since it emerged last year that Old Masters purportedly produced using replica materials have been traded for large sums of money and exhibited at leading museums.
Sotheby’s made a complaint in a New York court last week against the consignor of Saint Jerome, an oil on panel offered at auction in New York in 2012.
Catalogued as ‘Circle of Parmigianino (1503-40)’, the painting was estimated at $500,000-700,000 and sold at $800,000 (£509,650).
It was later loaned to the Met in New York and displayed as “attributed to Parmigianino”.
However, testing by forensic scientist James Martin, whose firm Orion Analytical was acquired by Sotheby’s last year, found traces of a modern synthetic pigment in “each and every one of  samples”.
The vendor is named in the complaint as Lionel de Saint Donat-Pourrieres who has refused to return the $672,000 he received from the sale, according to Sotheby’s claim.
Sotheby’s believe the picture is connected to the ‘Frans Hals’ portrait sold in a $10m private deal but which the company has since declared a fake. Sotheby’s has also confirmed that they are investigating two further works with a “combined value of less than £40,000”.
In a statement, Sotheby’s said: “We informed the purchaser from our January 2012 auction and initiated a process including technical analysis that established that the work was undoubtedly a forgery.”