Ann Freedman has filed a defamation suit against old master dealer Marco Grassi who was quoted in New York Magazine doubting whether the former Knoedler dealer had done any due diligence on the works she bought from Glafira Rosales. The suit will necessarily dwell on the definition of proper due diligence in an art transaction. Freedman’s suit claims the dealer received informal authentications. Whether this fits the definition of due diligence will likely become a pivotal fact of the case:

Presenting the case that she did due diligence in researching a collection of works that had never before been seen, Ms. Freedman in the lawsuit lists some 20 experts she says told her they were real, including curators from the Museum of Modern Art, the National Gallery of Art and the Solomon R. Guggenheim Museum. […]

According to the suit, she showed the paintings to a host of modern-art experts, and hired E.A. Carmean Jr., the former head of 20th-century art at the National Gallery of Art, to undertake a multiyear research project on a deceased art adviser who had purportedly played a role in their original sale.

“I believed, along with many, many other people, they were the real McCoy,” Mr. Carmean said.

The fact that they all turned out to be fake “does affect me,” he said. “I simply won’t offer an opinion as to whether something’s authentic again in the future. That’s done.”

In many cases, the opinions that Ms. Freedman gathered were informal, rather than official authentications. A curator at the National Gallery called two works “beautiful,” and a Guggenheim curator borrowed one for an exhibition, according to the suit.

Gallery President Files Defamation Suit (Wall Street Journal)