cookie files received from cookie file sources are screened based upon the recommendations of a service provider which downloads privacy protection criteria in the form of a “ watch list ” to a subscriber &# 39 ; s client machine . a user - friendly interface allows the subscriber to optionally modify the watch list prior to it being used at the subscriber &# 39 ; s client machine by assigning known cookie file sources to either a “ trustlist ” or a “ blacklist .” a “ composite list ” is then generated and used by the client machine to screen cookie files . the subscriber receives updates from the service provider on either a periodic or “ as - needed ” basis using a “ quick update algorithm .” a “ privacy scanning algorithm ” runs on the client machine and has two different modes of operation . the first is a continuous mode where unwanted cookie files are blocked from being stored at the client machine . the second is a periodic mode where the client machine is “ scrubbed ” of unwanted cookie files according to the privacy protection criteria .