Stamp auctioneer David Feldman has filed papers against the estate of notorious Qatari sheikh Saud bin Mohammed Al Thani following the sale of John du Pont's renowned collection of British Guiana stamps in June.
The sale saw dramatic results as the sheikh, renowned for his world-class art collection and failure to pay at several previous auctions, bid heavily for the British Guiana rarities.
Among the star lots was an 1850-51 2c, which saw a 90% increase on its $133,992 estimate to make $254,585.
Al Thani had agreed before the sale to make a 35% payment on his winning bids, with the rest due in instalments. However, by late September, he had already fallen behind on payments, and the Swiss auction house was forced to negotiate a new payment plan, which included an $872,000 down payment on his debt of $7.5m.
The sheikh died of unknown causes at the age of 48 on November 9, just one day before his Henry Graves Supercomplication watch - the most valuable in the world - auctioned for $24m.
The watch is said to be cursed, having brought bad luck to several of its past owners. Yet perhaps it is the Du Pont Collection of British Guiana that holds the curse, with John E Du Pont meeting an unhappy end following his purchases.
David Feldman states that it had obtained references for the sheikh prior to the sale from several other auction firms, despite Al Thani being well known for his big bids that rarely come to fruition. The suit states the company "reasonably believed that Sheik Al-Thani had the capability and intention of paying for any items he might purchase."
The sheikh is a distant cousin of the current Emir of Qatar and was given the role of Qatar's minister of culture from 1997-2005. However, he was dismissed from the job and placed under house arrest while his purchases were investigated, and later focused on private collecting.
His assets were frozen in 2012 following a dispute with Baldwin's and M&M Numismatics after he defaulted on bids he made during the sale of the Prospero collection of Greek coins.
Sotheby's name appears on the papers issued by David Feldman, with watches, books, diamonds, African masks and a Faberge egg among items still awaiting payment. However, it appears Al Thani was not behind the world record $9.5m purchase of the British Guiana 1c Magenta in June, which Sotheby's has already confirmed as paid for.
Sotheby's Financial Services is holding a large amount of Al Thani's valuables as collateral, and David Feldman is hoping that these can be sold to settle his debts with both Sotheby's and itself.
With Al Thani's bids pushing up prices at auction, and in some cases raising the market value to inflated prices, there are concerns among collectors that the value of their British Guiana stamps will be subject to a sharp correction. Other collectibles markets may also be affected by the sheikh's reckless bids.