Consumers, Privacy | featured news

The two-year-old drive to give consumers a simple way to block companies from tracking their behavior as they move across the Internet has faltered, say participants in the process who are struggling to reconcile privacy concerns with an advertising model that pays for many free Internet services.

In split-second auctions, companies are jockeying for the chance to buy online ads geared to your specific tastes. But consumer advocates see a risk of a computer-generated class system.

IT knows who you are. It knows where you live. It knows what you do. It peers deeper into American life than the F.B.I. or the I.R.S., or those prying digital eyes at Facebook and Google. If you are an American adult, the odds are that it knows things like your age, race, sex, weight, height, marital status, education level, politics, buying habits, household health worries, vacation dreams — and on and on.

The Federal Trade Commission has been gently pressuring the Internet advertising industry to reveal more information to consumers about how it collects data and targets ads.