Third Point urges Sotheby's chief William Ruprecht to quit Activist investor Dan Loeb launched a blistering attack on Sotheby's chief executive William Ruprecht on Wednesday, accusing him of lacklustre leadership and his managers of extravagant wining and dining that had cost shareholders "hundreds of thousands of dollars." The public attack, in an open letter addressed to Mr Ruprecht on Wednesday calling for his resignation, came after a federal filing revealed Mr Loeb's Third Point had upped its stake in Sotheby's to 9.3 per cent from 5.7 per cent. The hedge fund is now the largest shareholder in the New York-based auctioneer. IN Luxury 360 "Sotheby's is like an old master painting in desperate need of restoration," said Mr Loeb, adding that he was willing to join the Sotheby's board and that his team had already started to meet potential candidates to replace Mr Ruprecht. "While you were an able caretaker of Sotheby's during times of crisis, you have not shown the innovation or inspiration the company sorely needs to play offence today," he wrote in a letter disclosed in a regulatory filing. Mr Loeb said Sotheby's management had not fully grasped the importance of contemporary and modern art to Sotheby's future, and failed to develop a successful online sales strategy. He also accused the company's senior management of lavish and wasteful business practices, including expensive lunches and dinners where, he said, they "feasted on organic delicacies and imbibed vintage wines at a cost to shareholders of multiple hundreds of thousands of dollars." "We acknowledge that Sotheby's is a luxury brand, but there appears to be some confusion - this does not entitle senior management to live a life of luxury at the expense of shareholders," he said. The auctioneer responded with a statement saying that "rather than debating incendiary and baseless comments, we are focused on serving our clients" needs during this critical autumn sales season." It said it would comment on Mr Loeb's letter "at the appropriate time." "Sotheby's actions as a leader in the global art business have been producing superior results - including a share price increase exceeding the Standard & Poor's Midcap index over the one, five and 10-year periods," it added. Sotheby's has been under growing pressure from investors to review its financial policies in recent months. In September the company put its Manhattan headquarters up for sale, as Mr Loeb and others insisted management find ways of returning more cash to shareholders. Several high-profile Wall Street hedge funds alongside Third Point have consolidated long positions in the auctioneer this year, including Marcato Management, which announced it had taken a 6.6 per cent stake in August, and Trian Partners, which has a 3 per cent holding. The company has long enjoyed a near-duopoly in fine art auctions alongside London-based rival Christie's. However, in 2012, sales at Sotheby's totalled $5.4bn, down 7 per cent from 2011. In August, the company announced net profit in the first half of 2013 fell 7 per cent to $69.4m. Christie's, on the other hand, announced total 2012 sales of $6.27bn, up 10 per cent from the previous year, as well as grabbing valuable market share from Sotheby's in emerging markets. Mr Loeb has carved a reputation for himself as an incisive and often brutal adversary, unafraid of taking on recalcitrant executives or involving himself in potentially difficult situations. Earlier this year the 51-year-old Mr Loeb called on Japanese electronics group Sony to sell its entertainment business, raising eyebrows not only in Japan, a country where no love is lost for activist investors, but also closer to home, in Hollywood. Actor George Clooney labelled Mr Loeb a carpetbagger. It was only in July this year that Mr Loeb pulled out of another controversial activist position at Yahoo. Third Point bought into the company in 2011, ousted its management after an acrimonious proxy battle - in which it revealed chief executive Scott Thompson to have embellished qualifications on his résumé - and made about $1bn in profits after forcing through the sale of Yahoo's non-core assets and instituting a share buyback. Additional reporting by Sam Jones in London