What is the DoubleClick cookie doing on my computer?

If you have a DoubleClick cookie in your Cookies folder, it is most likely a DART cookie. The DoubleClick DART cookie helps marketers learn how well their Internet advertising campaigns or paid search listings perform. Many marketers and Internet websites use DoubleClick’s DART technology to deliver and serve their advertisements or manage their paid search listings. DoubleClick’s DART products set or recognize a unique, persistent cookie when an ad is displayed or a paid listing is selected. The information that the DART cookie helps to give marketers includes the number of unique users their advertisements were displayed to, how many users clicked on their Internet ads or paid listings, and which ads or paid listings they clicked on.

Why does your cookie keep coming back after I delete it?

When you visit any website or search engine on which DoubleClick’s DART technology is used, our servers will check to see if you already have a DART cookie. If the servers do not receive a DART cookie, the servers will try to set a cookie in response to your browser’s “request” to view that Web page. If you do not want a DART cookie with a unique value, you can obtain a DoubleClick DART “opt out” cookie. Alternatively, you can adjust your Internet browser’s settings for handling cookies. This is explained in the next question.

Use of Advertising Cookies

Certain 3rd party advertisers use cookies to serve advertising content based upon your prior search history, and activity on this site, which helps to display content most relevant to your needs. The Doubleclick Dart Cookie enables this functionality for Google.

If you don’t want cookies being used to track your browsing history, you can opt out of the Dart Cookie, or you can also opt out of other 3rd party cookies via the Network Advertising Initiative.