From Volume 76, Number 4 (May 2003)
Are Internet advertisers trespassing on our computers? The question arises due to the increasing reliance upon cookie technology by Internet advertising firms as the primary means to match online ads with the specific interests and characteristics of individual Internet users.
It seems that whenever we visit a Web site, we are barraged with an increasing number of blinking banner advertisements hocking products and services of every imaginable sort. More than sixty billion advertisements per month are carefully selected for us and sent to our computers by a single Internet advertising firm, DoubleClick, Inc. In order to increase the effectiveness of the ads, DoubleClick deposits small text files or “cookies” on our computers in addition to sending us the banner advertisements. Like most other Internet advertisers, DoubleClick uses cookie files to collect and maintain detailed consumer profiles that reflect the online practices, preferences and other personal characteristics of each individual who surfs the Web. Based on those detailed consumer profiles, DoubleClick places on the pages of affiliated sites various banner advertisements of client companies that target the specific interests of individuals who happen to visit any DoubleClick affiliated site. Since its inception, DoubleClick alone has placed billions of targeted banner advertisements for client companies on sites across the Internet and some estimate that those ads have been viewed by a majority of all Internet users. To date, DoubleClick has compiled perhaps as many as 100 million user profiles in its databases and, with more than 11,000 affiliated commercial Web sites, DoubleClick remains the largest Internet advertising firm in the world.