Patrick Drahi, the French-Moroccan billionaire currently making waves at BT, is mulling a listing of the Sotheby's auction house. Drahi has hired bankers to weigh up the potential for a float on the US stock market in 2022. Sotheby's was listed on the stock exchange for three decades before Drahi's swoop two years ago, with its possible return to the market coming after a strong year.