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Digital tracking explained

How ad tracking and real-time bidding work

An ad auction is a market for an impression. The information sent with a bid request deserves attention too.

Sources checked .

Conceptual illustration

An auction while a page loads

Google describes real-time bidding as buying and selling advertising inventory in less than a second. Its Authorized Buyers documentation says a buyer can evaluate and bid on individual ad impressions. This is a description of that system, not proof that every website uses it. Google: real-time bidding

What a request can carry

Google lists parameters including targeting information, an IP address, a referrer for branded sites and user identifiers. Which information is supplied depends on the request. A bid request and a completed ad impression are different events. Google: real-time bidding

Recognition is a separate mechanism

Cookies, pixels, browser characteristics and mobile ad identifiers can help recognize activity. An auction chooses an ad; tracking mechanisms can help connect the activity used for targeting. FTC: online tracking

Choose controls by collection route

Review browser cookie choices for websites and app tracking or advertising-ID choices on a phone. Mozilla also documents browser tracking protection. These controls address different parts of the process. Mozilla: tracking protection · Google: advertising ID · Apple: app tracking controls

Questions and answers

Does every bid request contain a name?

Google's introduction lists technical and targeting fields, not a guarantee that each request includes a person's name. Avoid treating a field specification as proof of an individual disclosure. Google: real-time bidding

Can browser controls help?

Yes, but their scope differs. Mozilla describes protections against several kinds of trackers, rather than a guarantee that all observation stops. Mozilla: tracking protection

Sources and scope

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