Mozilla has described its proposal for the technology which allows users to opt-out of the online behavioral advertising (OBA). According to this proposal, users will be allowed to set a browser preference to disable the OBA, and this information will be sent to websites using HTTP header.
Do Not Track
Mozilla’s Alexander Fowler describes, "We’re pleased to be able to share one of these efforts today in the area known as “Do Not Track,” which is best understood in current policy discussions to provide a way for people to opt-out of online behavioral advertising (OBA). [...] The Do Not Track header builds on the work the advertising networks have done to date without the cookie-based systems they make available to people online. The advantages to the header technique are that it is less complex and simple to locate and use, it is more persistent than cookie-based solutions, and it doesn’t rely on user’s finding and loading lists of ad networks and advertisers to work.".
More information on Mozilla’s Do Not Track is available here.
Google’s "Keep My Opt-Outs"
According to WSJ, Google may announce a privacy tool called "Keep My Opt-Outs" for Chrome users to opt out of ad-targeting.