The Globe and Mail reports in its Wednesday edition that Mastercard is warning partners responsible for adding merchants to its network that unlicensed vape sales violate its standards. A Reuters dispatch to The Globe says U.S. state attorneys-general in an April letter pushed Mastercard and other major card networks or payment processors to take stronger action to prevent their networks from being used to facilitate illegal vape sales. Those partners, also known as acquirers, are financial institutions that act as a go-between to complete credit-card transactions. Mastercard's global notice said when acquirers register a merchant they are "attesting that all appropriate controls are in place" to make sure their activities don't violate the law. It recommended those companies implement controls involving reviewing and approving a merchant's product inventories, along with transaction and invoice monitoring. Mastercard said it would launch investigations if stores selling illegal vapes used its services, potentially targeting both retailers and acquirers, with the risk of fines if they do not comply with their standards. "We have zero tolerance for unlawful activity on our network," Mastercard said in its notice.