The traditional auction house was founded in London in 1744 by the bookseller Samuel Baker (+1778), later George Leigh (+1816) and Baker's nephew John Sotheby (1740-1807) also joined the auction house. The last member of the Sotheby family to bear the name died in 1861, making Sotheby's about 15 years older than its direct competitor Christie's. The first auction took place on 11 March 1744 and included several hundred valuable books. Over the years, the business field expanded to include prints, medals, coins and paintings, and ultimately expensive wine rarities. In 1964, the American auction house Parke-Bernet was acquired, making Sotheby's the largest US auction house. Until 1977 Sotheby's was a British public limited company, in 1982 the company headquarters were moved to New York and one year later the US businessman Alfred Taubman took over the company. Approximately 1,500 employees work at 90 locations in 40 countries; around 300 auctions are held annually worldwide. In 2013 the company achieved a turnover of 854 million dollars.