Porter left Christie’s at the end of 2015 and has been on garden leave for a year, which included a two month trip to Turkey.
He will start the New York based role on January 17 as chairman of the auction firm’s recently created Fine Art division. The division, which focuses on 20th and 21st century art, was formed a year ago and is also chaired by Amy Cappellazzo and Allan Schwartzman who became part of Sotheby’s when their firm Art Agency, Partners was purchased for $50m.
Porter, who spent 25 years at Christie’s, is a law graduate and began his career at New York law firm Proskauer Rose.
At Christie’s, where his roles included chairman and president of Christie’s Americas, he was credited with securing major private collections such as those of actress Elizabeth Taylor and US collector and dealer in Asian art Robert Ellsworth.
Sotheby’s chief executive Tad Smith, said: “With more than 25 years in the art market, Marc is uniquely suited to take on an important leadership role at our company.”