How the DNT Header-based Opt-out Mechanism Works

The DNT header is a universal opt-out mechanism that your end-users can use to opt out of the tracking and targeting associated with audience segmentation. This opt-out mechanism does not rely on the opt-out cookie; rather, it relies on a privacy setting within a user’s web browser.

If a user’s browser passes the DNT header with a value of 1 (true), then OpenX behaves as if the user has an active opt-out cookie set in the same ad serving domain (it stops tracking the user). The location of the DNT setting varies between web browsers.

For example, Mozilla Firefox users can access the DNT setting through the Firefox > Preferences menu (the Privacy tab).

If a user selects the check box, their browser will pass the DNT: 1 header, turning off tracking for them.