At Art Fraud Trial, Sotheby’s Is Pressed on Role in Sales to Russian Oligarch

The painting Sotheby’s was trying to sell was a newly discovered work by one of the world’s greatest artists, Leonardo da Vinci. It was known as the “Salvator Mundi” and was a depiction of Christ.

But it had a code name: Jack.

Samuel Valette, a Sotheby’s specialist, testified in a Manhattan courtroom on Wednesday about how one day in March 2013 he had taken the painting crosstown in an S.U.V. from the auction house’s headquarters on York Avenue to a premier apartment overlooking Central Park.

It was one of the many trips he had made to display paintings for a prospective buyer, Valette said. He was, as usual, accompanied by security personnel, and the painting, already valued at tens of millions of dollars, was in a protective crate.

The apartment was owned by Dmitry Rybolovlev, a Russian oligarch who has sued Sotheby’s, accusing the auction house of aiding a Swiss dealer who he says defrauded him in the sale of several masterpieces.

Valette said he had not known whose apartment it was when he visited 15 Central Park West. Inside the home were two men, he said: the Swiss dealer, Yves Bouvier, a frequent client who had arranged the viewing, and Rybolovlev, whom he had met before.

But Valette insisted under questioning by Rybolovlev’s lawyer, Daniel J. Kornstein, that he had no idea whom the apartment belonged to.