Dark web in the dark: Investigating when transactions take place on cryptomarkets

Online illicit marketplaces known as cryptomarkets have gained considerable attention from the media, government authorities, law enforcement agencies, and researchers. An increasing number of studies have investigated various aspects of these cryptomarkets' characteristics, such as product categories, sale volumes, and the number of listings and vendors. However, there is a gap in the literature regarding whether illegal transactions (of illicit drugs) take place during the day or week. This study fills this gap by tracing Bitcoin addresses associated with the six previously leading and most active cryptomarkets—Silk Road, Silk Road 2.0, Agora, Evolution, Nucleus, and Abraxas—to identify the specific timings of these transactions. This study reveals clear patterns of activity on the marketplaces. First, transactions more often take place at night in European countries (Germany, Netherlands, the UK), the US, and Canada, where the cryptomarket drug trade is most active. Second, there are more transactions on Mondays, Tuesdays, and Wednesdays, and fewer on Saturdays and Sundays. This indicates that the retail drug trade accounts for a large part of the cryptomarkets. Further, this study examines the impact of a cryptomarket policing effort known as Operation Onymous, and indicates that this policing effort only displaced users among these marketplaces and did not deter their activity, even in the short-term. It also suggests that Operation Onymous did not alter users’ transaction patterns.