The change follows the $3.7bn acquisition of Sotheby’s by Patrick Drahi, a deal which was completed last month and took the company into private ownership after 31 years as a public company trading on the New York Stock Exchange.
Smith will now become a shareholder of the company and act as a senior adviser to Stewart.
The appointment Stewart means three senior executives have been replaced since Drahi took control of the company. It emerged earlier this month that both Sotheby’s chief financial officer Mike Goss and executive vice president and chief commercial officer John Cahill were leaving the company, with the CEO of Drahi’s family office Jean-Luc Berrebi now also taking on the role of Sotheby’s CFO.
Stewart served as co-president and chief financial officer at Altice USA since 2016, having previously worked for more than two decades in operations, financial and corporate leadership roles in the US, Latin America and Europe, most recently as CEO of Itau BBA International plc.
Prior to that, he spent 19 years at Morgan Stanley as an investment banker in various leadership and client-facing roles, based in New York, Brazil and London.
As with Smith, who joined Sotheby’s from MSG Media and MSG Entertainment, he enters the auction industry from a background outside the traditional art market.
Stewart helped grow the technology, telecommunications and entertainment branches of Altice USA and, notably, also led the company’s $2.1bn initial public offering on the New York Stock Exchange, the largest telecom IPO in 15 years.
Drahi said: “Charlie is a talented executive who brings years of international experience to Sotheby’s. I have known him for many years and have been impressed by his appetite for innovation, taking smart risks, and challenging the status quo.
“He has a proven record of driving growth and is ideally positioned to create value for Sotheby’s clients and our outstanding team.
“I also want to thank Tad Smith for his leadership over the past four and a half years. Sotheby’s reached a new level of success during his tenure and I am delighted we will continue to benefit from his experience in an advisory capacity.”
Stewart said: “I am thrilled to be joining such a successful and storied organisation… I look forward to adding my expertise to the talented global team and building on the success that has been established over nearly three centuries.”