Privacy proponents hit back.
"The online advertising industry has dropped its facade of negotiating Do Not Track in good faith," said Jonathan Mayer, one of two Stanford researchers who devised the HTTP header concept used by browsers to signal a user's DNT decision. "This week's letters to Microsoft and W3C leadership are part of that."
The Worldwide Web Consortium (W3C) is a standards-setting group that is trying to finalize DNT's implementation. The group is meeting this week in Amsterdam to continue discussions. Mayer is active in the W3C discussions.
Other privacy advocates were even tougher on the ANA and its demand that Microsoft reverse course.
"In recent days, we have suddenly seen an all-out blitz of attacks on Do Not Track, both in Washington and Silicon Valley, decrying Do Not Track as a disaster that would destroy the advertising-supported Web," said Leslie Harris and Justin Brookman of the Center for Democracy and Technology (CDT) in a Wednesday blog post.
Harris is the CDT's president and CEO, while Brookman is the advocacy group's director of consumer privacy.
Mayer noticed the uptick in rhetoric, too. "In recent weeks industry trade groups have turned to obstructionism and vitriol within the W3C multi-stakeholder process," Mayer said in an email reply to questions. "Outside the W3C, they've placed negative coverage, penned misleading op-eds and lobbied Republicans in Congress to challenge the FTC."
The ANA's blast against IE10 made some suspect it had been the tipping point. "It is possible that this uproar stems entirely from Microsoft's decision in June to aggressively steer its users to turn on Do Not Track during install," said Harris and Brookman.
Not so, countered an online ad executive.
Steve Minichini, who leads the interactive marketing group at the advertising agency TargetCast, disagreed that IE10 had been a trigger for any recent anti-DNT blitz on the part of advertisers. "We've been talking about this for years," Minichini said in a Wednesday interview.
He acknowledged that the debate had heated up, but blamed Microsoft. "The main reason there's so much conversation is the principle of it," said Minichini, referring to IE10's on-by-default setting. "IE10 will not have a big foothold in the market at first, but as the years roll on, year after year, it will grow. [Microsoft's move] is just a marketing strategy to grab headlines."
Some would agree with Minichini's point: Many Microsoft watchers and analysts have interpreted Microsoft's decision to push users to DNT as a way for it to differentiate the browser from competitors.
Microsoft is on somewhat shaky ground with IE; the browser has lost share for years, although that decline has slowed during 2012, according to California-based Net Applications, which on Monday said all versions of IE accounted for 53.6% of those used in September. (Irish metrics firm StatCounter, however, says that IE has shrunk to just 32.7%, second behind Google's Chrome.)
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