Sotheby's says a 16th century Italian painting sold by the auction house for $842,500 in 2012 is actually a modern fake, according to a complaint filed in U.S. District Court in New York on Tuesday.

The auction house is suing the collector who consigned the painting, arguing that he must pay back at least the $672,000 he personally made on the sale. Sotheby's says its contract with the man, Lionel de Saint Donat-Pourrieres, allows the company to rescind the sale if a painting turns out to be a counterfeit.

The painting, titled St. Jerome, had previously passed through the hands of an art dealer under investigation for allegedly trafficking multiple forged works.

It was displayed at Vienna's national gallery before it was auctioned off. The gallery identified it as the work of a man known as Parmigianino, an Italian Renaissance master who worked in Parma, Italy, in the early 1500s.

By the time Sotheby's received it in 2011, disputes among art historians had led many to conclude that the painting might have been created by someone close to Parmigianino, but not necessarily by the artist himself. One scholar, the auction noted in its catalog, thought the painting might actually be by another Renaissance-era Italian, Michelangelo Anselmi.

But no one disputed the basic origin of the painting. It was more than 400 years old, everyone who examined it agreed. That is, until a man named James Martin turned his attention to St. Jerome.

James Martin and the modern forgeries

Martin, the investigator behind Sotheby's complaint, is an art conservator and forensic scientist. One colleague referred to him as "the 'rock star' of his field," in an interview with Art New England magazine.

In October 2016, Martin's art analysis company, Orion Analytics, shocked the art world when it reported a painting attributed to a 17th century Dutch artist appeared to be a forgery. It contained materials that had not been invented until the 20th century.

What's more, the Dutch painting had come from the same art dealer as another suspected fake, signaling a master forger might be at work. The Financial Times reported that the news sent the market for paintings by so-called Old Masters reeling.

Sotheby's acquired Orion Analytics in December and made Martin the head of its new Scientific Research Department. Meanwhile, the auction house had begun to suspect that St. Jerome might be a fake. It had passed through the hands of an art dealer named Giuliano Ruffini, who the court complaint notes "is under investigation for selling a considerable number of Old Master Paintings that are considered to be modern forgeries."

Martin took pigment samples from 21 areas of St. Jerome, analyzing the composition of the paint and comparing the chemicals it contained with paints invented at different points in history.

"Each and every one of those samples (none of which were taken from areas of restoration) contained the modern synthetic pigment phthalocyanine green," the complaint stated.

That pigment was "first used in paints nearly four centuries after Parmigianino died."

"A wake-up call"

"It's one of the biggest scandals in my memory," Richard Feigen, an Old Master art dealer in New York, told Bloomberg after last year's revelations about forgeries in the market. "It's going to make people very wary, extremely careful about things they are offered and the sources of those things."

The St. Jerome complaint only exacerbates that concern. Bob Haboldt, a dealer in Old Master art, told The New York Times that Tuesday's court complaint was "a wake-up call."

"It'll make people look at what they have on the wall or what's on consignment or what's been purchased in the recent past more closely. People are scrutinizing what's in their collections, and I think that's an ongoing process."

But, Haboldt told the newspaper, "I don't think it'll shake up the market more than it already has, because if you notice, the sales results at auction and in the market haven't changed."

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