Based on a recent study conducted in a major motor vehicle sales jurisdiction within North America, Auto Ad SentryTM reduced the presence of unlicensed motor vehicle dealers (curbstoners) in online classifieds websites by 24%. The study was carried out using data gleaned from a popular online classified from June through December 2012. Curbstoners were identified as having 3 or more motor vehicles listed for sale within that time period. From September through December 2012, Auto Ad Sentry contacted 850 curbstoners using a combination of pre-recorded telephone messages, and SMS text messages. The study found that 201 curbstoners stopped posting ads after being contacted by Auto Ad Sentry. By taking away the primary marketing tool for curbstoners, a state regulator can curtail such unlicensed motor vehicle sales in their jurisdiction with a cost-effective strategy.