It will be interesting to see the extent of an auctioneer's responsbility for opinions expressed about the authenticity and legitimacy of artefacts it handles which will emerge from a case going through the courts at the moment:
Sotheby’s is being sued for damages over a work it attributed to a “follower” of Caravaggio that sold at auction in London to the late collector and scholar Sir Denis Mahon in 2006, for a hammer price of £42,000. Mahon subsequently identified the painting as a work “by the hand of Caravaggio” and obtained an export licence for it that gave an estimated selling price of £10m, according to a claim filed at London’s High Court of Justice. The claimant is Lancelot William Thwaytes, who consigned the work to auction in 2006 [...] Thwaytes seeks unspecified damages, interest and costs relating to the price difference between the £42,000 the painting sold for in 2006 and “what its true open market value was in 2006”, had it been attributed to Caravaggio and to be determined by expert evidence. The filing includes the claim that Sotheby’s did not undertake the necessary research and analysis prior to the work’s sale.I would see this sort of process operating in future the other way round, a collector buys an item presented as from a legitimate source by the catalogue - suggesting a 'reputable' auctioneer had done the research to verify that - but then finds the object unsaleable for anything like the price they paid for it because it then transpires that previously to coming to the auctioneer, the object had 'surfaced' (from underground?) on the market in the hands of a dealer known to be trading in illicit artefacts, with no traces of any earlier collecting history.
Sotheby's downplay their own role in the affair:
Sotheby’s adds: “Our view is also supported by the market, which gave its verdict on this painting when it set the price at £50,400 [the hammer price plus the buyer’s premium] at Sotheby’s sale in December of 2006. The catalogue in which the painting was included was distributed among the world’s leading curators, art historians, collectors and dealers—had they deemed the attribution different to that given in the catalogue, the price realised would doubtless have reflected that”.So now they are suggesting that their catalogue descriptions are meaningless? They might as well have offered it as "painting, looks a bit like a Caravaggio" and let the mrket sort it out. Likewise: "A vase, looks ancient Greek, pretty clean", "sculpture, believed to be marble, a bit battered and stained but pretty", "metal thing, found by metal detectorist in Europe, state as in photograph".
Melanie Gerlis, 'Sotheby’s sued over Caravaggio attribution', The Art Newspaper February 14 2013. February 15, 2013
Vignette: A version of the "Cardsharps".