A Sotheby's employee walks past Luciano II painted in 1976 by Franz Gertsch.

While the art market has shown signs of strength since the election, Sotheby's CEO Tad Smith credits Donald Trump's policies more than Trump himself.

"It doesn't matter who is president," he told CNBC. "What matters is whether the policies are pro-growth. Whether they're friendly for taxation, whether they're friendly for economic development.
As long as we have that, I think people will feel better."

Growing confidence in the art market helped lift Sotheby's earnings in the fourth quarter and helped lift the company's share price 15 percent Monday. Its share price has doubled over the past year.

Investors are betting that the art market slowdown, which began at the end of 2015 on China fears, may be reversing and that Sotheby's will be better able to capitalize on the growth under Smith's leadership and after changes at the company.

Sotheby's kicks off Wednesday its important London sales, offering up more than $300 million worth of art for auction. The sales will be a big test of the market after Trump's inauguration.