The letter emphatically states that Redmond's decision will, "undercut the effectiveness of our members' advertising and, as a result, drastically damage the online experience by reducing the Internet content and offerings that such advertising supports. This result will harm consumers, hurt competition, and undermine American innovation and leadership in the Internet economy."

The ANA board members are calling on Microsoft to change its position, but the software giant is not likely to budge given its history.

Indeed, this won't be the first time Microsoft has endured backlash from advertisers over the DNT settings in IE 10. When Microsoft got bashed in August for the move, Brendon Lynch, Microsoft's chief privacy officer, said the company's goal was "designing and configuring IE features to better protect user privacy, while also affording customers control of those features."

Butting Heads

The ANA, though, is hitting harder this time. The Oct. 1 letter points out that IE has a 43 percent market share in the United States. By setting the Internet Explorer browser to block data collection, they argue, Microsoft's action could potentially eliminate the ability to collect Web viewing data of up to 43 percent of the browsers used by Americans.

"The Internet is a tremendous engine of economic growth and a platform for enhancing our daily lives. It has become the focus and a symbol of the United States' famed innovation, ingenuity, inventiveness, and entrepreneurial spirit," the letter says. "It is data that fuels this engine and supports the vast array of online offerings that define the consumer online experience."

Microsoft issued a statement Tuesday that sounds much like Lynch's August statement. Microsoft said its approach to DNT in IE 10 is part of its commitment to privacy by design and putting people first.

"We believe consumers should have a consistent experience and more control over how data about their online behavior is tracked, shared and used," Microsoft said. "We also believe that targeted advertising can be beneficial to both consumers and businesses. As such, we will continue to work towards an industry-wide definition of tracking protection."

A Healthy Debate

Greg Sterling, principal analyst at Sterling Market Intelligence, observed that the system is voluntary and third parties can choose to circumvent or ignore it, which is what the letter suggests.

"Marketers are upset because this will make their jobs more challenging. Most consumers -- especially those on the IE browser -- will not change their default settings and so it will make millions of people more difficult to track and target," Sterling told us.

"Still, it's good that Microsoft's action is fostering debate about balancing the interests of marketers to track users and their online behavior with those of consumers who often don't wish to be tracked. The issue is more nuanced and complex than either side will allow."

Scott Thomas:

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