I first posted about this case back in 2017 under the headline "Here's what can happen when you say a work is fake."
The district court dismissed the case in 2018.
Now the Ninth Circuit has reversed. You can read the decision here.
The main grounds for reversal had to do with the issue whether the defendant had to have known the specific identity of the plaintiff at the time of the allegedly defamatory statements (answer: it did not), but the Court also threw in the following:
1. Rejection of the district court’s conclusion that a jury could not conclude that certain of the statements at issue -- which remember were typical authenticity statements -- implied “an assertion of objective fact under the circumstances." In other words, a statement that a work is inauthentic can be considered an assertion of fact for purposes of a defamation claim.
2. Rejection of the argument "that an assertion that a painting is a fake is categorically not a communication that may be defamatory of a seller who has sold—and warranted—it as authentic." In other words, a statement that a work is inauthentic can, depending on the circumstances, form the basis of a claim that the seller has been defamed.
3. Holding that, whether or not the authentication claims "might be understood as an opinion," a jury "could easily find otherwise given the language used." In other words, a statement that a work is inauthentic is not necessarily opinion (and therefore can in theory form the basis of a defamation claim).
So once again: here's what can happen when you say a work is fake. As a general rule, it's still a good idea to keep quiet.