Google's use of the DoubleClick cookie enables it and its partners to serve ads to your users based on their visit to your sites and/or other sites on the Internet.
Users may opt out of the use of the DoubleClick cookie for interest-based advertising by visiting Ads Settings.
Notify your site visitors of the third-party vendors and ad networks serving ads on your site.
Provide links to the appropriate vendor and ad network websites.
(The DoubleClick cookie)
The DoubleClick cookie is used by Google in the ads served on the websites of its partners, such as websites displaying AdSense ads or participating in Google certified ad networks. When users visit a partner's website and either view or click on an ad, a cookie may be dropped on that end user's browser.