New research commissioned by the IAB and presented at its board meeting this week shows that as many as 12 percent of consumers don't accept third-party cookies--that is, the cookies set by ad servers and analytics companies that track the Web sites that consumers visit and the ads they view, among other data.

The IAB board this week discussed the possibility of conducting some sort of public awareness campaign designed to educate Web users about how publishers and advertisers actually use cookies. Last year, the IAB planned to work with Safecount--an organization formed last April by Carat Fusion executive (and MediaPost "Online Spin" columnist) Cory Treffiletti and Dynamic Logic president Nick Nyhan--to promote cookies to consumers.

Instead, the IAB reportedly decided to wait for more information--including data showing whether cookie deletions and rejections are increasing over time, holding steady, or declining. Even now, the organization might still wait to determine whether rejections increase before launching a promotional effort.

Greg Stuart, CEO of the IAB, declined to comment.

The IAB's research was based on observations of consumer behavior, as opposed to asking consumers whether they accept cookies--methodology criticized in the past on the grounds that consumers are not necessarily aware of how their computers treat cookies. Although a 12 percent rejection rate appears high, it's consistent with at least some other research; last year, analytics company WebTrends also reported that around 12 percent of consumers delete cookies.

The extent of cookie deletions or rejections by consumers has been debated since March 2005, when Jupiter Research reported that 39 percent of consumers delete cookies at least monthly. At the time, the research roiled many industry executives, who had long assumed that consumers ignored cookies.

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