A new study published by INFORMS Information Systems Research suggests that the selective targeting of large vendors on darknet markets may be a more cost-effective approach to combatting dark web drug sales than coordinating the takedown of entire markets. The study found that news of the arrest of a major vendor tended to have an impact on vendors on the same market, discouraging them from continuing sales, while also having a dampening effect on the activity of smaller vendors selling similar products.
The study, which analyzed mainly older, defunct darknet markets (including Silk Road 2, Evolution, and Agora) also found that the total number of vendors on a market tended to drop after the arrest of a major vendor on that market. Most of the vendors leaving a market after an arrest were smaller in terms of sales. Conversely, sales from the largest vendors, who tended to remain, actually increased after an arrest, picking up customers from the fallen vendor.

Study figures indicate a sharp drop-off in total reviews left and vendors remaining on a darknet market within a few weeks after news of the arrest of a major vendor on the market.
The authors of the study thereby concluded that the targeting of high-level vendors on a darknet market by law enforcement presented a cost-saving alternative to attempting to shut down the market itself. It is suggested to be an effective alternative due to an average decline of transactions on a market after a large vendor bust of about 39%, with a decrease in total vendors on the market of 56% over the same period.
โBy looking at various outcomes from the policed site Silk Road 2 with those from nonpoliced sites, Agora and Evolution, we find that enforcement efforts on the policed site dramatically reduced subsequent transaction levels and the number of remaining vendors,โ said Jason Chan, one of the studyโs principal authors. โThis result suggests that the policing effort induced a negative shock to the dark web ecosystem in which a significant proportion of drug sellers decided to exit altogether,โ he concluded.
The study also found that arrests of major vendors of more dangerous drugs tended to have a greater โshockโ effect on smaller vendors and were more likely to encourage them to cease their career as a vendor. Meanwhile, arrests of large vendors offering less dangerous drugs were less likely to have such an effect on smaller vendors of the same drugs.