The onus to stop payments would ultimately be on Western banks, the researchers conclude.

"If (i.e.,banks that provide credit cards to U.S. consumers) were to refuse to settle certain transactions (e.g., card-not-present transactions for a subset of Merchant Category Codes) with the banks identified as supporting spam-advertised goods, then the underlying enterprise would be dramatically demonetized. Furthermore, it appears plausible that such a "financial blacklist" could be updated very quickly (driven by modest numbers of undercover buys, as in our study) and far more rapidly than the turn-around time to acquire new banking resources --a rare asymmetry favoring the anti-spam community. "