The antiquities catalogues of major auction houses comprise an accessible long-term source of information about the auction market in antiquities and the market in antiquities more generally. The information contained in these catalogues has been used to investigate the nature and scale of the market and to assess the impact of legal and normative measures of market control. But, by way of two case studies, referencing Iraqi and Cambodian material sold at the New York branch of Sotheby’s, this article argues that, while auction catalogues do provide an invaluable source of information for investigating the antiquities market, it can be misleading. Changing material or monetary statistics might reflect commercial factors unrelated to market control. For more reliable research, long-term auction data should be contextualized with information available from other sources.