The letter was the harshest criticism yet by the advertising industry of Do Not Track in general and Microsoft's position with IE10 specifically. The ANA used phrases like "fundamentally bad for consumers," "undermines consumer interest" and "cheat society" in its missive.
Essentially, the ANA argued that if advertisers could not track users on the Web -- and then use that information to deliver targeted online ads to them -- the Internet as it's now known would vanish. IE10's on-by-default stance threatened that tracking.
"Microsoft's decision to block collection and use of information by default will significantly reduce the diversity of Internet offerings and potentially cheat society of the robust offerings that are currently available," the ANA said.
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.