Pinterest is the latest major Internet service to support Do Not Track.

The social site, which allows its users to organize items of interest, made the announcement on Friday in a note that explained how it was going to suggest personalized pins based on websites the user has visited and placed a Pin It button.

“We’re excited to give everyone a more personalized experience, but we also understand if you’re not interested!” wrote software engineer Ke Chen.

DNT is a browser setting that tells websites the user does not want cookies dropped onto their computer, nor do they want their activities tracked online. Since the specification is not an approved standard and is mired in conflicting political and business debates, websites can choose to ignore the signal. Tracking user activity is central to online advertising efforts; delivering targeted advertising based on a user’s browsing and search history is the basis for Internet companies’ business models.

Internet Explorer 10, which started shipping with Windows 8, was the first major browser to have DNT turned on by default, but the Apache HTTP Server Project last September included a patch in its web server that ignores the DNT setting. Apache cofounder Roy Fielding argued that the default setting does not represent the user’s privacy preference. Opponents countered that the patch would impact users who chose to enable DNT during a custom installation, thus ignoring their wishes.

Since then, other browsers have offered the DNT setting. Firefox chief privacy officer Alex Fowler said 14 percent of the Mozilla browser’s users have opted in to DNT. Last November, Google announced that it would support DNT starting with Chrome 28. Twitter was among the first to support DNT, doing so as of May 2012.

“People are asking for a different level of privacy on your service, and you have to listen to that. It’s critical to the business and web ecosystem,” Fowler said at the RSA Conference this year. “At Mozilla, we also do online advertising campaigns and email outreach. We try to think about the tracking we impose on users, so we are making an effort to work with vendors who are willing to respect the DNT header. It’s not a condition, but we think it’s important for organizations advocating for this that we spur service providers to understand and respect it.”

Pinterest, meanwhile, said it will follow any settings users have in their browsers regarding cookies and tracking. It also provided its users with step-by-step instructions on how to enable DNT and set up a webpage explaining how Pinterest uses data it collects about a user’s web activity.

Every time a Pinterest user visits a site and embeds a Pin It button, a tracking cookie is dropped on the user’s machine that communicates to Pinterest as the user moves around the Web. Pinterest said it tracks only the movements and does not associate activity with a user identifier such as an email address.

“Unless you opt out, the data collected by Pinterest will paint an astonishingly intimate portrait of one’s online browsing activity,” said Rainey Reitman of the Electronic Frontier Foundation. “And when a user is logged in and has a Pinterest account, this browsing activity is associated with her account.”

Pinterest said it will use the data it collects to suggest boards for its users. Users who enable DNT will be opted out.

“Whenever it receives the Do Not Track signal (DNT:1), Pinterest will ‘zero’ its tracking cookies – removing the identifiers so they can no longer be associated with the websites you have visited in the past,” the EFF’s Reitman said. “While simple for a company to do, zeroing a tracking cookie is a powerful mechanism for protecting users’ web privacy.  It means that a company can’t use their tracking cookies to create a detailed portrait of your online activities.”

Image courtesy mkhmarketing.

Categories: Privacy