Stanford University researchers found that at least one ad network apparently is still using the technique to gather information about what links users have clicked on and which sites they ve visited. Epic Marketplace was using a script to test thousands of URLs per second against a user s history to see whether the user has been to the sites. Epic said in a blog post responding to the Stanford research, Epic officials disputed the researchers findings and said that what the script is doing is called segment verification
Source: https://threatpost.com/researchers-find-browser-history-sniffing-still-ongoing-072211/75462/