• by Wendy Davis , Staff Writer @wendyndavis, February 24, 2011

In the fall of 2007, a coalition of privacy groups and digital rights advocates first proposed that consumers should be able to eschew all online tracking through a comprehensive do-not-track list.

It took a while for the idea to catch on with regulators, but the Federal Trade Commission made clear in December that it likes the concept. Even more significant, the major browser manufacturers are on board.

Microsoft's IE9, Mozilla's Firefox and Google's Chrome all are offering variations of do-not-track. Firefox is offering a do-not-track header, which alerts other sites that visitors don't want to be tracked. But that system is voluntary, meaning that it only works if the Web sites that use tracking data agreed to honor the headers. Google's Chrome browser is now offering a "Keep My Opt-Outs" extension that allows users to permanently opt out of online tracking and ad targeting, but only by the companies that participate in the industry's self-regulatory program.

Microsoft's feature, which rolled out earlier this month, allows users to download lists of servers to block or allow. When ad networks and other Web companies are blacklisted, Internet Explorer 9 will prevent them from appearing as third parties on publishers' sites. The tracking protection feature only blocks third parties, so it won't prevent publishers from serving their own ads.

Today, Microsoft's do-not-track tool advanced significantly with the news that the World Wide Web Consortium, or W3C, is considering the feature. "Just as the community has worked together at the W3C on interoperable HTML5, we can now work together on an interoperable (or universal, to use the FTC privacy report's term) way to help protect consumers' privacy," the company says. "The proposal with the W3C is a significant step toward enabling an industry standard way for Web sites to (1) detect when consumers express their intent not to be tracked, and (2) help protect themselves from sites that do not respect that intent."