A trial over a multimillion-dollar art-forgery scandal that toppled one of New York’s most respected art galleries abruptly came to a close when the gallery, Knoedler & Co., and a related company settled a $25 million lawsuit filed by art collectors Domenico and Eleanore De Sole.

Lawyers for Knoedler and the De Soles announced the agreement Wednesday morning, the day the gallery’s former president, Ann Freedman, and owner, Michael Hammer, were expected to testify in Manhattan federal court.

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