Which Browsers Do and Don't Use "Do Not Track”

By Katie Kindelan Comment

Just one month after the federal government issued calls for a “Do Not Track” option to regulate online advertising, both Mozilla and Google announced that they will be offering up ways for Firefox and Chrome users to opt out of behavioral tracking. But where can consumers find the new features, what exactly do they offer, and will they really work?

The new steps from Google and Mozilla come on the heels of Microsoft’s announcement a few months back that it would introduce a “Do Not Track” tool on the next generation Internet Explorer, and polls showing widespread public support for such an option. Mozilla’s steps, in particular, make Firefox the first Web browser to specifically follow the Federal Trade Commission’s model of a do-not-track system.

Here is an overview of the latest options:


Google’s new “Keep My Opt-Outs” privacy feature is available now as an extension for download in Chrome and enables you to opt out permanently from ad tracking cookies. It’s essentially a browser extension that strengthens the Network Advertising Initiative system that has been in place for years. Under this system, consumers can, and must, ask to opt-out of being tracked by NAI members. The participating members then embed a cookie in the user’s browser to stop the tracking and stop sending targeted ads to the user. This latest tool, though, enables users to save their opt-out preferences even when a browser’s cookies have been cleared. Before, once a user’s history was erased, so too was their opt-out preference. Another benefit is that the new tool allows users to opt out of all participating ad networks at once, rather than one at a time, but users will still be required to opt-out of ad tracking themselves.

Internet Explorer 9

The privacy feature in IE9 looks a lot like Google’s Chrome feature, except that it will monitor clickstream tracking and targeted ads from a list of ad networks and block them, eliminating the Chrome “middle man” syndrome of having to rely on NAI members to send users a cookie to honor the opt-out requests. But, still to be determined and finalized is just where the list of ad networks will come from. One option on the table is to have consumers create their own lists of ad networks they want blocked, or to choose from lists compiled by privacy groups. And, left up to consumers, will be the task of updating their IE9 browsers with their latest list of preferred ad networks to block.

Mozilla Firefox

Firefox is proposing an alternate to Google’s solution that will rely on HTTP headers rather than cookies. In this case, a “Do Not Track” header would be appended to indicate to the service that the user does not want to be tracked. But their “Do Not Track” feature has one big loophole: for the tool to work, ad tracking companies must opt-in to the system, and agree not to monitor web-surfing habits of users who have chosen to opt-out. However, so far at least, according to the Wall Street Journal, no companies have agreed to participate in Firefox’s “Do Not Track” program. “Mozilla recognizes the chicken and egg problem,” Alexander Folower, Mozilla’s global privacy head, wrote in a blog post announcing the new tool. Mozilla has not made clear if the new tool will be ready to be included in the upcoming Firefox 4.0 release, or a later version of the software.

The jury is still out among tech experts and privacy advocates on whether any of these tools will actually work. We’ve reported ourselves on why the “Do Not Track” feature may not do for online behavioral targeting what it did for telemarketing.

TechNewsWorld calls Mozilla’s effort a “PR ploy,” but the company is widely being praised by both the FTC and the privacy advocacy group EFF for the new header tool. Google, on the other hand, is garnering less praise, mainly because the system remains “opt-out,” dependent on cookies, and only applicable within the top 15 advertising networks.

As they stand now, the Mozilla approach appears much closer to what both the FTC and Commerce Department have proposed. An F.T.C. spokeswoman remarked to the New York Times, “We’re pleased that Google is engaged in the process, but Mozilla and Microsoft are clearly steps ahead.”