Lord Renfrew of Kaimsthorn--the former Disney Professor of Archaeology at Cambridge University--made a speech in the House of Lord, part of the UK Parliament, at the end of October 2009. He was concerned that auction-houses in the UK continued to sell antiquities that had undocumented provenance. In other words their "collecting histories" could not be traced back to a period before the 1970 UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property. Renfrew drew particular attention to the case of a London auction-house that had to withdraw a large number of lots on the eve of its October 2008 sale at the request of the Italian government. It appeared that items featured in photographs seized during a police raid in a warehouse in Switzerland. Renfrew added, "It is scandalous that this practice continues."

It has now emerged that two ancient pots, an Apulian situla and an Athenian red-figured pelike, have been seized by agents of the US Immigration and Customs Enforcement (ICE) after passing through a New York sale earlier in the summer. Both appear to have surfaced through an antiquities gallery in Beverly Hills before passing into a private North American collection. Initial reports suggest that the two pieces also feature in the Geneva dossier.

In early June this year a Corinthian wine-mixing krater was seized by agents of ICE at a New York auction-house. The krater also featured in the Geneva photographs and is reported to have first emerged on the market through a London auction-house.

These seizures are a reminder that objects that have been ripped from their archaeological contexts continue to surface on the antiquities market. Some may have passed through a series of earlier sales or private collections.

These "toxic" lots can weaken confidence among buyers. Should auction-houses and dealers in such archaeological material decline to handle material that was not recorded prior to 1970?